Biology Complete Fill In The Blanks Important 2014

Biology Complete Fill In The Blanks Impotent 2014

Complete the following sentences with appropriate answers:

1. Cell was discovered in 1665 by _________.
2. Fungi cannot make their own food because they lack _________.
3. The physical and chemical breakdown of food in humans first begins in the _________.
4. During respiration _________ is released from food.
5. The different parts of human body and their functions are described in the book _________ written by Abdul Malik Asmai.
6. The study of tissues is called _________.
7. The hormone insulin is secreted by _________.
8. Tape-worm belongs to the phylum _________.
9. The fourth whorl of a flower is known as _________.
10. Stem increases in thickness due to _________.
11. The distance between two nodes of a stem is called _________.
12. “Al-Mansoora” is written by _________.
13. The third eyelid (transparent membrane) that protects the eye of frog in water is known as _________.
14. The organs of locomotion in _________ are called Setae.
15. _________ supplies blood to the brain and to the parts associated with the brain of forg.
16. The genes representing a pair of contrasting characters are called _________.
17. Firdous-ul-Hikma is written by _________.
18. Star-fish belogns to the phylum _________.
19. Androecium is the _________ whorl of a flower.
20. Goitre is caused by the deficiency of _________.
21. Fish respires by means of special structures called _________.
22. _________ controls all functions of a cell.
23. A long narrow and cylindrical fruit of Brassica compestris is called _________.
24. The transfer of pollen grains from another to the stigma of carpel is called _________.
25. Excretory organs in insects are called _________.
26. The single major contribution of Muslim scientists in the field of scientific method is use of _________.
27. The two main subdivisions of biology are _________ and _________ each of which has several further branches.
28. Life can be best defined by comparing _________ of living things with those of _________ things.
29. When food is burnt in our cells in the presence of oxygen to produce energy the process is called _________.
30. When a cell divides to produce two new cells exactly like the parent the process is called _________.
31. The sum of chemical reaction in cells is called _________.
32. Cells were described for the first time by _________.
33. The tiny organs of a cell are called _________.
34. Fungi cannot make their own food because they lack _________.
35. Mosses belong to the group called _________.
36. Invertebrates with spiny skins and hard plates, are known as _________.
37. Birds possesses _________ bones.
38. The major distinguishing feature of vertebrates in the presence of _________.
39. Mango is an Angiosperm plant with two cotyledons. So it belongs to the subgroup called _________.
40. The internal factor necessary for photosynthesis in plants is _________.
41. Glucose produced by photosynthesis may be transformed into complex carbohydrates and other _________ which are utilized by plants or stored in edible plant parts.
42. Plants, which feed on other plants and harm them, are called _________.
43. Plants that feed on dead organic matter are called _________.
44. Some plants are specially adapted to get their food by _________ mode of nutrition.
45. Organic compounds in our food consisting of carbon, hydrogen and oxygen are called _________.
46. Glucose and fructose combine to form a 2-sugar carbohydrate called _________.
47. One gram of glucose releases about _________ calories of energy.
48. The total number of known amino acids is _________.
49. All organisms need food for _________.
50. The building blocks of proteins are _________.
51. Physical and chemical breakdown of food in man first begins in the _________.
52. The blind sac at the juction of small and large intestine is called _________.
53. Wave-like automatic contractions of the gut are called _________.
54. The basic processes of transport of substances in cells of all organisms are _________ and _________.
55. Plants transport water, minerals and food from region to region by a _________ system.
56. Too rapid evaporation of water in hot weather causes loss of _________ pressure in plant cells and _________ of plants.
57. Leaves remain cool even in sunlight due to the cooling effect of _________.
58. Heart failure may occur due to _________.
59. Hear muscle is different from _________ in working continuously and automatically without experiencing fatigue.
60. A blockage in the _________ stops the flow of blood and oxygen to muscles of the heart.
61. Respiration takes place in _________ cells of a plant while photosynthesis occurs only in _________ parts.
62. During respiration _________ is released from food.
63. Breathing means _________ of oxygen and carbon dioxide with the _________.
64. Food is prevented from entering the larynx by _________ which guards the opening into it.
65. Oxygen from the lungs is transported to the cells in the form of _________.
66. The volume of the thoracic cavity increases when muscles of the rib cage and the diaphragm _________.
67. The control center for breathing is located in the _________.
68. The capillary network enclosed in Bowman’s capsule is called _________.
69. Persons suffering from kidney failure can be helped either by such artificial means as _________ or by _________ transplants.
70. Excretion involves removal of _________, excess _________ and _________.
71. Nitrogenous wastes are produced when _________ are metabolized.
72. Extra quantities of CO2, O2 and water in plants is released through _________.
73. Like animals, plants too are _________ to environmental factors.
74. Any environmental factor to which plants react is called a _________ whereas the reaction itself is called a _________.
75. Support and movement human being is a function of _________ and _________.
76. The body of invertebrates such as arthorpoda is protected and supported by an _________.
77. The joints of skull bones are of _________ types.
78. Ligaments hold the _________ together.
79. The type of muscle which makes possible movements of a vertebrate animal is called _________.
80. Co-ordination of various activities of the body in multicellular animals is not possible without _________ systems.
81. Single-celled organisms are too small to need special means of _________ of information.
82. Large animals have developed two special systems of communication namely _________ and _________ systems.
83. The structure which perceive environmental stimuli are called _________.
84. The main effectors in the body of animals are _________ and _________.
85. Glands without duct are called _________.
86. Tissues and organs, which respond to hormones, are called _________ sites.
87. The endocrine gland, which controls the function of thyroid, adrenal, ovary and testis, is called _________ gland.
88. Hormones are substance made by _________ and are released directly into _________.
89. Budding results in new individuals by the process of _________ division.
90. The a***ual method of reproduction in yeast is _________.
91. The 3rd and 4th whorls of flower are _________ and _________.
92. Fusion of sperm with the egg results in formation of a _________ with _________ number of chromosomes.
93. The part of the seed which contains nourishment for the embryo is called _________.
94. The development of a tadpole to become an adult frog is called _________.
95. The science which deals with the study of viruses, bacteria, protozoa and microscopic fungi is called _________.
96. Some bacteria can reproduce so fast that they can produce almost _________ generations in 24 hours.
97. Food can be preserved by _________, _________ and _________.
98. Genetic engineering is a branch or area of _________.
99. Biological principles which explain similarities and differences among individuals are called _________.
100. The science which deals with structure and working of DNA and genes inheritance is called _________.
101. Chromosomes consist of _________ and _________.
102. An individual receives _________ percent of its chromosomes from each parent during ***ual reproduction.
103. An ecologist specializes in learning about interrelationships _________ and their interaction with _________ environment.
104. The components of environment are _________ and _________.
105. The place where organisms live is called _________.
106. The different living thing component in an ecosystem constitute a _________.
107. The basic functional unit of environment is an _________.

GLOSSARY OF BIOLOGY::: 9th Class Notes

Abiogenesis: Early theory that held that some organisms originated from nonliving material.

Abnormal hemoglobin: Hemoglobin molecule with a different shape due to an altered amino acid sequence (ultimately caused by an altered DNA base sequence), such as in the inherited disease sickle-cell anemia.

Abscisic acid: A plant hormone that promotes dormancy in perennial plants and causes rapid closure of leaf stomata when a leaf begins to wilt.

Absolute time: One of the two types of geologic time (relative time being the other), with a definite age date established mostly by the decay of radioactive elements, although ages may also be obtained by counting tree rings, decay of a specific type of atom, or annual sedimentary layers (such as varves in lakes or layers in a glacier). The term is in some disfavor because it suggests an exactness that may not be possible to obtain.

Absorption: The process by which the products of digestion are transferred into the body's internal environment, enabling them to reach the cells.

Absorptive feeders: Animals such as tapeworms that ingest food through the body wall.

Acetylcholine: A chemical released at neuromuscular junctions that binds to receptors on the surface of the plasma membrane of muscle cells, causing an electrical impulse to be transmitted. The impulse ultimately leads to muscle contraction.

Acetyl CoA: An intermediate compound formed during the breakdown of glucose by adding a two-carbon fragment to a carrier molecule (Coenzyme A or CoA).

Acid: A substance that increases the number of hydrogen ions in a solution.

Acid rain: The precipitation of sulfuric acid and other acids as rain. The acids form when sulfur dioxide and nitrogen oxides released during the combustion of fossil fuels combine with water and oxygen in the atmosphere.

Acoelomates: Animals that do not have a coelom or body cavity; e.g., sponges and flatworms.

Acquired immunodeficiency syndrome (AIDS): A collection of disorders that develop as a result of infection by the human immunodeficiency virus (HIV), which attacks helper T cells, crippling the immune system and greatly reducing the body's ability to fight infection; results in premature death brought about by various diseases that overwhelm the compromised immune system.



Actin: The protein from which microfilaments are composed; forms the contractile filaments of sarcomeres in muscle cells.

Action potential: A reversal of the electrical potential in the plasma membrane of a neuron that occurs when a nerve cell is stimulated; caused by rapid changes in membrane permeability to sodium and potassium.

Active transport: Transport of molecules against a concentration gradient (from regions of low concentration to regions of high concentration) with the aid of proteins in the cell membrane and energy from ATP.



Adaptation: Tendency of an organism to suit its environment; one of the major points of Charles Darwin's theory of evolution by natural selection: organisms adapt to their environment. Those organisms best adapted will have a greater chance of surviving and passing their genes on to the next generation.

Adaptive radiation: The development of a variety of species from a single ancestral form; occurs when a new habitat becomes available to a population. Evolutionary pattern of divergence of a great many taxa from a common ancestral species as a result of novel adaptations or a recent mass extinction. Examples: mammals during the Cenozoic Era after the extinction of dinosaurs at the close of the Mesozoic Era flowering plants during the Cretaceous Period diversified because of their reproductive advantages over gymnosperm and non-seed plants that dominated the floras of the world at that time.

Adenine: One of the four nitrogen-containing bases occurring in nucleotides, the building blocks of the organic macromolecule group known as nucleic acids (DNA and RNA). Adenine is also the base in the energy carrying molecule ATP (adenosine triphosphate) which is the energy coin of the cell.



Adenosine diphosphate (ADP): Lower energy form of ATP, having two (instead of the three in ATP) phosphhate groups attached to the adenine base and ribose sugar.

Adenosine triphosphate (ATP): A common form in which energy is stored in living systems; consists of a nucleotide (with ribose sugar) with three phosphate groups. The energy coin of the cell.

Adhesion: The ability of molecules of one substance to adhere to a different substance.

Adrenocorticotropic hormone (ACTH): A hormone produced by the anterior pituitary that stimulates the adrenal cortex to release several hormones including cortisol.

Adventitious roots: Roots that develop from the stem following the death of the primary root. Branches from the adventitious roots form a fibrous root system in which all roots are about the same size; occur in monocots.

Age structure: The relative proportion of individuals in each age group in a population.

Aggregates: Fairly random associations of animals with little or no internal organization; form in response to a single stimulus and disperse when the stimulus is removed; one of the three broad classes of social organization.

Albinism: Genetic condition caused by the body's inability to manufacture pigments; an autosomal recessive trait.

Aldosterone: A hormone secreted by the adrenal glands that controls the reabsorption of sodium in the renal tubule of the nephron.

Alleles: Alternate forms of a gene.

Allergens: Antigens that provoke an allergic reaction.

Alpha decay: Type of radioactive decay in which a radioisotope emits a large but slow-moving particle consisting of two protons and two neutrons.

Alternation of generations: A life cycle in which a multicellular diploid stage is followed by a haploid stage and so on; found in land plants and many algae and fungi.

Altitudinal gradient: As altitude increases, a gradient of cooler, drier conditions occurs.

Alveoli: Tiny, thin-walled, inflatable sacs in the lungs where oxygen and carbon dioxide are exchanged.

Amensalism: A symbiotic relationship in which members of one population inhibit the growth of another population without being affected.

Amino acids: The subunits (monomers) from which proteins (polymers) are assembled. Each amino acid consists of an amino functional group, and a carboxyl acid group, and differs from other amino acids by the composition of an R group.



Amino acid sequence: Also known as the primary structure of a protein/polypeptide; the sequence of amino acids in a protein/polypeptide controlled by the sequence of DNA bases.

Amniocentesis: A method of prenatal testing in which amniotic fluid is withdrawn from the uterus through a needle. The fluid and the fetal cells it contains are analyzed to detect biochemical or chromosomal disorders.

Amniote egg: An egg with compartmentalized sacs (a liquid-filled sac in which the embryo develops, a food sac, and a waste sac) that allowed vertebrates to reproduce on land.

Amoebocytes: Amoeboid cells in sponges that occur in the matrix between the epidermal and collar cells. They transport nutrients.

Amphibians: Class of terrestrial vertebrates which lay their eggs (and also mate) in water but live on land as adults following a juvenile stage where they live in water and breathe through gills. Amphibians were the first group of land vertebrates; today they are mostly restricted to moist habitats.

Anabolic reactions: Reactions in cells in which new chemical bonds are formed and new molecules are made; generally require energy, involve reduction, and lead to an increase in atomic order.

Anaerobic: Refers to organisms that are not dependent on oxygen for respiration.

Analogous structures: Body parts that serve the same function in different organisms, but differ in structure and embryological development; e. g., the wings of insects and birds.

Anaphase: Phase of mitosis in which the chromosomes begin to separate.

Anaphylaxis: A severe allergic reaction in which histamine is released into the circulatory system; occurs upon subsequent exposure to a particular antigen; also called anaphylactic shock.

Androecium: Collective term applied to all of the male (stamen) parts of the flower.

Aneuploidy: Variation in chromosome number involving one or a small number of chromosomes; commonly involves the gain or loss of a single chromosome.

Angina: Chest pain, especially during physical exertion or emotional stress, that is caused by gradual blockage of the coronary arteries.

Angiosperms: Flowering plants. First appearing at least 110 million years ago from an unknown gymnosperm ancestor, flowering planbts have risen to dominance in most of the world's floras. The male gametophyte is 2-3 cells contained within a pollen grain; the female gametophyte is usually eight cells contained within an ovule which is retaind on the sporophyte phase of the plant's life cycle.

Animalia: Animal Kingdom. Multicellular eukaryotic group characterized by heterotrophic nutritional mode, usually organ and tissue development, and motility sometime during the organism's life history.

Annuals: Plants that grow and reproduce sexually during one year.

Antagonistic muscles: A pair of muscles that work to produce opposite effects&emdash;one contracts as the other relaxes: for example, the bicep and tricep muscles on opposite sides of your upper arm.

Anther: The top of a stamen's filament; divided into pollen sacs in which the pollen grains form.



Antibiotics: Substances produced by some microorganisms, plants, and vertebrates that kill or inhibit the growth of bacteria.

Antibiotic resistance: Tendency of certain bacteria to develop a resistance to commonly over-used antibiotics.

Antibodies: Proteins produced by immune system cells that bind to foreign molecules and microorganisms and inactivate them.

Antibody-mediated immunity: Immune reaction that protects primarily against invading viruses and bacteria through antibodies produced by plasma cells; also known as humoral immunity.

Anticodon: A sequence of three nucleotides on the transfer RNA molecule that recognizes and pairs with a specific codon on a messenger RNA molecule; helps control the sequence of amino acids in a growing polypeptide chain.



Antidiuretic hormone (ADH): and released by the A hormone produced by the hypothalamuspituitary gland that increases the permeability of the renal tubule of the nephron and thereby increases water reabsorption; also known as vasopressin.

Antigenic determinant: The site on an antigen to which an antibody binds, forming an antigen-antibody complex.

Antigens: Molecules carried or produced by microorganisms that initiate antibody production; mostly proteins or proteins combined with polysaccharides.
Aorta: The artery that carries blood from the left ventricle for distribution throughout the tissues of the body. The largest diameter and thickest walled artery in the body.

Apical meristem: A meristem (embryonic tissue) at the tip of a shoot or root that is responsible for increasing the plant's length.

Apnea: A disorder in which breathing stops for periods longer than 10 seconds during sleep; can be caused by failure of the automatic respiratory center to respond to elevated blood levels of carbon dioxide.

Apocrine glands: Sweat glands that are located primarily in the armpits and groin area; larger than the more widely distributed eccrine glands.

Appendicular skeleton: The bones of the appendages (wings, legs, and arms or fins) and of the pelvic and pectoral girdles that join the appendages to the rest of the skeleton; one of the two components of the skeleton of vertebrates.

Appendix: Blind sac at the end of the large intestine that usually ruptures during final exams; a vestigial organ in humans.

Archaea: Proposed, but not widely accepted, sixth taxonomic kingdom that would include the archaebacteria.

Archaebacteria: Ancient (over 3.5 billion years old) group of prokaryotes; some biologists want to place this group into a separate Kingdom, the Archaea. Most currently place it within the Kingdom Monera.

Archaeocyathids: An extinct group of animals that were part of Cambrian-aged reef environments, but which were extinct by the close of the Cambrian Period.

Archean/Proterozoic Era: The period of time beginning 4.6 billion years ago with the formation of the Earth and ending 570 million years ago.

Aridity: The condition of receiving sparse rainfall; associated with cooler climates because cool air can hold less water vapor than warm air. Many deserts occur in relatively warm climates, however, because of local or global influences that block rainfall.

Arrector pili: A muscle running from a hair follicle to the dermis. Contraction of the muscle causes the hair to rise perpendicular to the skin surface, forming "goose pimples."

Arteries: Thick-walled vessels that carry blood away from the heart.

Arterioles: The smallest arteries; usually branch into a capillary bed.

Artificial selection: The process in which breeders choose the variants to be used to produce succeeding generations.

Ascomycetes: Division of fungi that contains the yeasts and morels; ascomycetes produce an ascus (or sac) in which ascospores are produced.

Ascus: Structure produced by sac fungi in which sexual ascospores develop.

Asexual reproduction: A method of reproduction in which genetically identical offspring are produced from a single parent; occurs by many mechanisms, including fission, budding, and fragmentation.

Assortment: A way in which meiosis produces new combinations of genetic information. Paternal and maternal chromosomes line up randomly during synapsis, so each daughter cell is likely to receive an assortment of maternal and paternal chromosomes rather than a complete set from either.

Aster: Short fibers produced by cells during mitosis and meiosis. These radiate from the centriole (if it is present).

Asteroid impacts: Hypothesis that links certain mass extinction events with the impact of a comet or asteroid, most notably the mass extinction 65 million years that caused the disappearance of dinosaurs and many other reptilian groups. Asteroid impacts early in earth history also contributed to the formation of the atmosphere and oceans.

Asthma: A respiratory disorder caused by allergies that constrict the bronchioles by inducing spasms in the muscles surrounding the lungs, by causing the bronchioles to swell, or by clogging the bronchioles with mucus.

Asymmetrical: In animals, a term referring to organisms that lack a general body plan or axis of symmetry that divides the body into mirror-image halves.

Atmosphere: The envelope of gases that surrounds the Earth; consists largely of nitrogen (78%) and oxygen (21%).

Atom: The smallest indivisible particle of matter that can have an independent existence.

Atomic number: The number of protons in the nucleus of an atom.

Atomic weight: The sum of the weights of an atom's protons and neutrons, the atomic weight differs between isotopes of the same element.

Atrioventricular (AV) node: Tissue in the right ventricle of the heart that receives the impulse from the atria and transmits it through the ventricles by way of the bundles of His and the Purkinje fibers.

Atrioventricular (AV) valve: The valve between each auricle and ventricle of the heart.

Auricle: The chamber of the heart that receives blood from the body returned to the heart by the veins. Also referred to as atrium.

Autonomic system: The portion of the peripheral nervous system that stimulates smooth muscle, cardiac muscle, and glands; consists of the parasympathetic and sympathetic systems.

Autosomes: The chromosomes other than the sex chromosomes. Each member of an autosome pair (in diploid organisms) is of similar length and in the genes it carries.

Autotrophic: Refers to organisms that synthesize their nutrients and obtain their energy from inorganic raw materials.

Autotrophs: Organisms that synthesize their own nutrients; include some bacteria that are able to synthesize organic molecules from simpler inorganic compounds.

Auxins: A group of hormones involved in controlling plant growth and other functions; once thought responsible for phototropism by causing the cells on the shaded side of a plant to elongate, thereby causing the plant to bend toward the light.

Axial skeleton: The skull, vertebral column, and rib cage; one of the two components of the skeleton in vertebrates.

Axillary buds: Buds borne in the axil (where the leaf meets the stem) of a stem.

Axons: Long fibers that carry signals away from the cell body of a neuron

MUSLIM SCIENTISTS WITH THEIR WORK

Definition:
Science can be defined as study
"mainly concerned with the phenomenan of physical universe any or all of natural sciences or biological sciences."
or
Science as the "the field of study which attempts to describe and understand the nature of the universe in whole or part."

Science is the faculty to reason out the how and why of the things as they occur in the phenomenal world or the objective world..Basically science is the study of laws of nature and man has developed science by observing.Infact this subject has completely transformed our power over nature and the world outlook.Development of the modern technology is directly the outcome of the development of modern science.Without the scientific revolution the industrial revolution would not have been possible.

It has raised the human activity level by signifiacnt observations in the various fields of human existence.Whether its the exploration of human health,industrial progress,agrarian developments and modern communication technologies,the benefits gained from this major subject are enormous.Infact it would not be wrong to say that we are living in the age of science and is a dominant factor in our day to day existence.

2.CONTRIBUTIONS OF MUSLIM SCIENTISTS:

MUHAMMAD BIN MUSA AL KHWARZIMI:

Made lasting contributions in the fields of Mathematics,Astronomy,Music,Geography and History.He composed the oldest works on Arithmetic and on Algebra.The oldest Mathematic book composed by him is "Kitab ul jama wat tafriq"
He is the first person who used zero and wrote"Hisab ul jabr Wal Muqabla" which is conceived to be an outstanding work on the subject which included analytical solutions of linear and quadratic equations.
In the field of Astronomy he compiled his own tables which formed the basis of later astronomical pursuits in both East and West.
He also contributed in the field of geographical science by writing a noteworthy book KItab ul surat al ard. in Arabic.
His book " kitab al Tarik" is also a memorable work regarding history.

AL BERUNI:

Born in Afghanistan Beruni made original an important contributions to science.He is conceived to be the most prominent scientists of the Islamic world who wrote around 150 books on various signifiacnt subjects concerning human existence.These subjects include Mathematics,History,Archeology,Biology,Geology,Che m istry ,Religion etc.
He discussed the behaviour of earth,moon,and planets in his book "Qanoon Almasudi" which is also considered as an outstanding astronimical encyclopedia.He also discovered seven differnt ways of finding the directions of north and south and discovered mathematical technques to determine exactly the beginnig of the seasons.
Another noteable discovery he made was that the speed of light is faster than sound .His wide range of scientific knowledge is also revealed through his books" kitab al saidana" and "kitab al jawahar" dealing with medicine and the types of gems their gravity respectively.
He was a prolific writer whose works showed his verstality as a scientist.


AL RAZI:

The famous philosopher and a noteable surgeon of the Muslim world,Zakriya Al Razi was born in Ray near modern Theran Iran.His eagerness for knowledge lead him to the study of Alchemyand Chemistry,philosophy,logic ,Mathematics and Physics.He was a pioneer in many areas of medicine and treatment of health sciences in general,and in particular he worked alot in the fields of paeditrics,obsterics and opthalmology.
Al razi was the first person to introduce the use of Alcohal for medical purposes and opium for the objective of giving anaethseia to his patients.
In the field of opthalmology too Al razi gave an account of the operation for the extraction of the catract and also the first scientist to discover the effect of the intensity of light on the eye.The modern studies confirm his understanding on the subject thus making him a great physician of all the times.

ABU ALI IBN E SINA:

Endowed with great powers of absorbing and retaning knowledge this Muslim scholar also made valuable contributions to the field of science.He is considered to be the founders of Medicine and also added his great efforts to the fields of Mathematics,Astronomy,Medicinial Chemistry,Philosophy,Palae ontology and Music.
His most famus book is "Al Qannun" which brings out the features of human physiology and medicine.
Sina is also considered as a father of the science of Geology on account of his invaluable book on mountains in which he discussed matters relating to earth's crust and gave scientific reasons for earthquakes.He is the author of 238 books which are fine instances of his thoughts regarding various subjects in diverse ways.

JABIR BIN HAYAN:

Introduced experimental research in chemical science which immensly added its rapid development and made him the Father of Chemistry.He devised methods for preparation of important chemicals like hydrochloric acid,nitric acid,and white lead.
Jabir's work also deal with the refinement of metals ,preparation of steel,dyeing of cloth and leather,use of magnese dioxide in glass making,distillation of vinegar to concentrate acetic acid.
Jabir also explained scientifically two principle functions of chemistry,i.e., calcination,and reduction and registerd a marked improvement in teh methods of evaporation,sublimation,distillation and crystillization
He wrote more than 100 books which are one of the most outstanding contributions in the field of science especially the chemical science.

ABDUL HASSAN IBN AL HAITHAM:

One of the most outstanding Mathematicians, Physiologists,and Opticians of Islam.He contributed to the relams of medicine and philosophy.He wrote more than 200 scientific works on diverse subjects.
Haitham examined the refraction of light rays through transparent objects including air and water.
Infact he was the first scientist to elaborate two laws of refelction of light
He made a number of monumental discoveries in the field of optics ,including one which locates retina as the seat of vision.His book on optics "Kitab Al Manazir" vividly shows his grip on the subject.
He constructed a pinhole camera and studied formation of images .Due to his noteworthy contributions he is regarded as one of the prolific Muslim scientists of all times.

OMAR AL KHAYAM:

He was an outstanding Mathematician and Astronomer.He was also known as a poet,philosopher and a physician.He travelled to the great centres of learning of the era i.e. Samrakund,Bukhara,and Ispahan.He classified many algebric equations based on their complexity and recognized thirteen different forms of cubic equation.He also classified algebric theories of parallel lines.On the invitation of Sultan Jalal-ud- Din ,he introduced the Jilali calender which has an error of one day in 3770 years.He also developed accurtae methods for determination of gravity
As a poet too,he is known for his Rubaiyat.He made great contributions in the development of mathematics and analytical geomatry which benefitted Europe several years later.

NASIR UD DIN TUSI:

Al tusi was one of the greatest scientists,Mathematicians,Astronomers,Philosophers ,Theologians and physicians of his time.He was a prolific writer and wrote many treatises on varied subjects like Algebra,Arithmetic,Trignometry,Geometery,Logic,Met aphy sics,medicine,ethics and Theology.
He served as a minister of Halaku Khan and persuaded him to establish an observatory and library after the destruction of baghdad.He worked at the observatory and prepared precise tables regarding the motion of teh planets.These are also known as "Tables of Khan"

ZIA UD DIN IBN BAITAR:

Was a famous botanist and pharmacopist of middle ages.Because of his intensive travels,he was able to discover many plant species.He wrote many books regarding his field of speciality and is always considered as a prominent scientist among his Muslim counterparts

INTRODUCTION TO BIOLOGY LECTURE BY AAMIR KHAN MAHAR

Virus, Bacteria and Cyanobacteria

Micro-Organisms A large number of living things are present in this world. Some of them are large and some are small. Majority of the organisms are so small that they re not seen with naked eyes. For their observation, we need a light microscope or even an electron microscope. These microscopic organisms are called micro-organisms.
Micro-organisms As a Heterogeneous Group
Micro-organisms are a heterogeneous group. It includes different kinds of organism viruses, bacteria, cyanobacteria, protozoa, certain algae and some fungi. On the basis of structure they range from sub-cellular to cellular for example, viruses are sub-cellular and all other micro-organisms are cellular. Bacteria, and cyanobacteria are prokaryotes (without nucleus) where as algae, fungi and protozoa are eukaryotes (with nucleus). On the basis of mode of nutrition algae are autotrophic while fungi and protozoa are heterotrohic. Therefore, micro-organisms differ in their structure and mode of characteristics of viruses, they are studied in a separate group where as bacteria and cyanobacteria, being prokaryotes, are included in kingdom Monera.
Viruses
1. Virus is a Latin word which means “Poison”. Viruses are so small that they can only be seen with electron microscope.
2. Viruses have charcteristics of both living and non-living things.
3. Structurally they are not like, cell and are only made up of proteins and nucleic acids.
4. When they enter the body of any living organisms, they reproduce there like living organism.
5. They look like non-living crystals when they are out of the body of a living organism.
6. That is why they are placed between living and non-living things.
7. All viruses are parasites and cause different diseases in their hosts.
8. Viruses were discovered by Iwanowsky in 1892 from infected tobacco leaves. In 1935 W.M. Stanley isolated viruses in crystalline form from infected leaves of tobacco and observed them under electron microscope.
Size of Virus
Viruses are of different sizes. Their size varies from 0.01um to 0.03um(um is micrometer = 1/10,00,000 meter)
Shape of Virus
Viruses are of different shapes some are rounded, few are rod shaped, few polyhedral while some viruses look like tadpoles.
Structure of Virus
Viruses have same biochemical nature. In spite of their different shapes, they are made up of only two parts, an outer “coat”, and an inner “core”. The core is made up of DNA or RNA (never both) and the coat is made of protein. The outer protein coat determines the shape of viruses. e.g. in bacteriophage (virus that lives in bacteria) protein coat consists of two parts, head and tail. DNA is present in the head region but the tail has only protein. Most of the animal viruses contain DNA whereas plant viruses have RNA core bacteriophage is also called phage virus.
Viral Diseases in Plants
Ring spot in different plants, yellow in sugar beet and mosaic disease in tobacco, potato, tomato, bean and cabbage are the various diseases of plants, caused by viruses.
Viral Diseases in Animals
Mouth and foot disease in cattle and cowpox in horses, buffalo and cows are caused by viruses.
Viral Diseases in Humans
In human beings, viruses produce common cold, influenza, small pox, yellow fever, polio, infectious hepatitis, cancer and AIDS.
Ways of Viral Transmission
1. Through droplets produced during coughing and sneezing.
2. Through contact.
3. By air, contaminated water and food.
4. Through insects.
5. By reuse of already used syringes.
6. By un-sterilized surgery equipments.
Bacteria
Bacteria are found every where in air, water, living and dead bodies of organisms and even in glaciers and hot springs. These are unicellular micro-organisms.
Discovery of Bacteria
Leeuwenhoek discovered bacteria in 1697 for the first time. Later, Louis Pasteur and Robert Koch worked on them. They discovered that bacteria produce many diseases in men and animals.
Size of Bacteria
Bacteria (singular : bacterium) range from 1um to 10um in length and from 0.2um to 1um in width and can be observed under light microscope.
Types of Bacteria
On the basis of shape and form, bacteria are of four types. These are as follows:
1. Rounded – Cocci (singular; coccus)
2. Rod-like – Bacilli (singular; bacillus)
3. Spiral shaped – Spirilla (singular; spirillum)
4. Comma like – Vibrios (singular; vibrio)
Bacteria occur both singly and in colonies. Cocci bacteria are found in groups of two or four, or in irregular groups and even in the form of long beads. Baccilli are found singly or may join end to end to form long threads. But Spirilla and Vibrios occur singly.
(Diagram)
Structure of Bacteria
1. Bacteria are single celled prokaryotic organisms.
2. Bacterial cell is surrounded by a cell wall which is made of carbohydrates and amino acids.
3. Some bacteria have an additional slime capsule around their cell wall, which protects them and prevents them from drying.
4. Ribosomes help in synthesis of proteins. Nucleus is absent in bacterium. However, only a single large circular molecule of DNA is present which is surrounded by a clear zone of cytoplasm. It is known as nucleoid. This is not bounded by a nuclear membrane.
5. In addition to main bacterial DNA small, circular molecules of DNA called plasmids are also found. Plasmids play an important role in transmission of some heredity characteristics. Plasmids are also used a vectors in genetic engineering.
6. Motile (which can move) bacteria like bacilli are spirilla have one or more thread like flagella (singular; flagellum) which help them in their locomotion. Non motile bacteria like cocci lack flagella.
Economic Importance of Bacteria
It is generally thought that bacteria are fatal and harmful organisms and there is no beneficial aspect. But this is wrong impression. There are number of bacteria which are not only beneficial for mankind but are also essential for living system. Bacteria play very important role in the life of living organisms.
Beneficial Bacteria
Ecological Importance
These, along with fungi, help to decompose dead organisms and their refuse into simpler substances replenishing the raw materials in the soil and atmosphere and can thus purify the environment.
Bacteria and Nitrogenous Compounds in Soil
These bacteria are called nitrogen fixing bacteria. Another kind of bacteria live in the soil, called nitrifying bacteria which convert ammonia into nitrite and then to nitrate, enhancing the amount of nitrogen in the soil. In this way fertility of soil is increased.
Industrial and Commercial Purposes
1. These are used in manufacturing butter, cheese and yogurt.
2. These are used in processing of commercial fibers, leather, coffee, tobacco and vinegar.
Bacteria Synthesize Enzymes
Bacteria synthesize cellulose enzyme in the stomach of herbivore animals which helps in the digestion of food. Some bacteria also synthesize vitamin “B” and “K” in the large intestine of man and other mammals.
Bacteria as Bio-Insecticides
Recently the use of bacteria in bio-insecticides has become popular.
Harmful Bacteria
1. Bacterial decomposition on one hand is beneficial but on other hand causes damage to food, wood, clothes and other things.
2. Denitrifying bacteria in soil decrease the amount of nitrogen in soil and reduce the soil fertility. These are called identifying bacteria.
3. Many bacteria are harmful and cause many diseases in plants, such as canker disease in citrus fruits, rot and fire blight in peach, pear and apple, and potato scab in potato.
4. In animal like cattle bacteria cause T.B and anthrax. Bacteria also cause many diseases in man like T.B, Whooping Cough, Diphtheria, Typhoid, Pneumonia, Tetanus, Plague, Bacterial Dysentery, Cholera, Leprosy etc.
Ways of Bacteria Transmission
1. Whooping cough, Diphtheria, T.B and Pneumonia causing bacteria are transmitted from one person to other person through sneezes and cough droplets released in air.
2. Bacteria causing Typhoid and Cholera, are transmitted from one organism to another through contaminated water and food.
3. Plague and bacterial dysentery read through vectors like flies and animals.
Cyanobacteria
1. Cyanobacteria are also called blue green algae. They are simplest living organisms which have the ability to manufacture their own food by photosynthesis.
2. Structurally they resemble bacteria. Bacteria and Cyanobacteria are prokaryotes and they are placed in kingdom Monera.
3. Generally Cyanobacteria are found in moist places like of trees, rocks and soil, fresh water and oceans.
4. Some of them are symbionts and some are epiphytes.
5. Cyanobacteria are usually unicellular and solitary.
NOSTOC
A common example of cyanobacteria which has filamentous structure which is found in the form a ball is called Nostoc.
Characteristics of Nostoc
The important characteristics of Nostoc are:
1. It has a filamentous structure which form a ball like structure of Nostoc.
2. It floats on water.
3. Each filament of Nostoc is unbranched and has a single row of rounded or oval cells.
4. Each cell of Nostoc has double layered wall.
5. The protoplasm is differentiated into two parts.
6. Endoplasmic reticulum, mitochondria, golgi bodies and vacuoles are not present in the structure of Nostoc.
7. Heterocyst are found which help in nitrogen fixation.
8. Nostoc is an autotroph like other Blue-green-Algae.
Taxonomic Position of Nostoc
According to new classification, Nostoc belongs to kingdom prokaryota or Monera.
Structure of Nostoc
The structure of Nostoc is filamentous. The filaments are interring mixed in agelatinuous mass forming a ball like structure. It floats on water. A single filament looks like a chain of beads. Each filament is unbranched and has a row of rounded or oval cells

RESPIRATION

Respiration
The oxidation of the absorbed food material in order to obtain energy is called respiration.

There are two types of Respiration in the organisms:
1. Aerobic Respiration
2. Anaerobic Respiration
1. Aerobic Respiration
In most of the higher and larger organism, the glucose etc is oxidized by using molecular oxygen. This type of respiration is known as Aerobic Respiration. In aerobic respiration a mole of glucose is oxidized completely into carbon dioxide and water releasing enormous amount of energy. One glucose molecule in this resnpiration produces 686,000 calories of energy. Aerobic respiration thus produces 20 times more energy than the anaerobic respiration.
In aerobic respiration food is oxidized in presence of molecular oxygen.
Stages of Aerobic Respiration
There are two stages of Aerobic Respiration:
(a) External Respiration
In this stage, the organisms take the air (containing oxygen) into their bodies. This is called external respiration. this stage includes the transport of oxygen obtained from the inhaled oxygen to each cell of the body.
(b) Internal Respiration
The second stage is called internal respiration. It consists of the oxidation of glucose, amino acid and fatty acids etc, with molecular oxygen. In this stage all these reactions are included which extract the chemical energy of glucose and other compounds and store it in the form of ATP molecule, this respiration is also called cellular respiration as it occurs within cells.
In the internal or cellular respiration glucose and other compounds are passed through such enzymatic reactions which release the chemical energy gradually in small amounts with the help of which ATP molecules are synthesized.
2. Anaerobic Respiration
Some organisms oxidize their food without using any molecular oxygen. This is known as Anaerobic Respiration. In this type of respiration considerably less amount of energy is released as compared with the other type of respiration.
In anaerobic respiration a glucose molecule is broken down into two molecules of lactic acid with a release of only 47,000 calories of energy.
Glucose ——–> 2 Lactic Acid + Energy (47,000 calories)
Importance of Anaerobic Respiration
1. When earth came into being its environment was totally devoid of oxygen. The aerobic organisms cannot lie in anaerobic environment. The early organisms started respiration in the absence of oxygen to produce energy for survival of organisms.
2. Some existing organisms like bacteria and parasites which live in oxygen environment have anaerobic respiration.
3. Many useful bacteria and yeasts are anaerobic.
4. Even in the aerobic respiration of the first phase is anaerobic. The glycolysis which is the first phase of carbohydrate metabolism involves reaction which does not require the expenditure of molecular oxygen. This proves the idea that aerobic organisms have evolved from anaerobic organisms.
5. In our skeletal muscles, although aerobic metabolism takes place but in sustained activity when the oxygen supply cannot keep pace with energy demand, anaerobic respiration supplies the energy continuously by the breakdown of glucose to lactic acid.
ATP (Adenosine Triphosphate)
It is a chemical compound. ATP is an abbreviation of adenosine triphosphate. Its name indicates that it contains adenosine and three phosphate groups. Adenosine is formed of a nitrogenous base called adenine and a sugar called ribose. In ATP three phosphate groups are attached to the adenosine in a series one after the other.
Significance of ATP
ATP is a big source of energy. The two terminal bonds between the phosphate groups contain large amount of the chemical energy. When these bonds are broken in enzymatic reaction, large amount of energy is released by which energy requiring activities are accomplished, like synthesis of various compounds of carbohydrates, fats, proteins and hormones etc or for carrying out any physical work like muscle contraction, heat production or transport of substances etc.
When the terminal bond is broken the ATP is changed into ADP and phosphate 7300 calories of energy are released.
Gaseous Exchange in Plants
Plants get their energy from respiration. Plants have no special organ or system fro exchange of gases. The gaseous exchange in plants occurs in cells, of every part of the plant i.e. roots, stems and leaves etc according to their energy demand. The conducting system (xylem and phloem) of plants transports water and nutrients but plays no role in the transport of gases. The air spaces present between the cells of parenchyma of leaves, stem and roots are involved in the gaseous exchange.
Gaseous Exchange in Leaves and Young Stems
In the leaves and young stems, gaseous exchange occurs through stomata. Some gaseous exchange also occurs through cuticle.
Gaseous Exchange in Woody Stems and Roots
In woody stem and roots, there are present dead cells beneath the epidermis which form cork tissue. Later on, this tissue becomes porous. The pores are called lenticels. These are involved in gaseous exchange.
Gaseous Exchange in Leaves
The aquatic parts obtain oxygen for their respiration by diffusion from the dissolved oxygen in water. Whereas the land plants get their oxygen from air directly through their stomata which are more abundant on the lower surface than the upper surface of leaves.
Gaseous Exchange in Roots
The roots get their oxygen for gaseous exchange through diffusion from the air existing in the space between soil particles.
Process of Respiration in Plants
The respiration in plants continues day and night. In this process, the oxygen from the airspaces in the leaves and stems is diffused into tissues and cells after getting dissolved in the film of water which is present over the cells. In the cells this oxygen oxidizes the carbohydrates and other organic compounds into carbon dioxide and water to produce energy. Some of the water (vapours) comes in the airspaces from where they diffuse out to the atmosphere through lenticels and stomata. The elimination of carbon dioxide is more evident from the parts without chlorophyll like growing seeds and buds. The water produced in this process becomes a part of the already present water in the body of plants. The various chemical reactions of respiration are controlled by the specific enzymes. This process occurs at a faster rate in the parts of the plant having rapid growth like growing seeds, buds, apical meristem of roots and shoots, because these parts require more energy to accomplish the growth process.
Relationship between Respiration and Photosynthesis
The gaseous exchange in plant is not very evident during the day time as the products of respiration i.e. carbon dioxide and water are used in the process of photosynthesis. In the bright sunshine, because of high rate of photosynthesis the carbon dioxide produced in respiration falls short and therefore, some carbon dioxide has to be taken into the plant from outside for photosynthesis.
In the day time the plants therefore, take in carbon dioxide and expel out oxygen. The process of photosynthesis occurs in chloroplasts whereas the process of respiration takes place in cytoplasm and mitochondria.
Gaseous Exchange in Animals
The gaseous exchange in different animals takes place by different methods and organs. In unicellular aquatic animals like amoeba, the dissolved oxygen in water diffuses directly through their cell surface into the interior of the animal and the carbon dioxide similarly diffuses out from their bodies into the external water. This is the simplest way of gaseous exchange and it can occur only in small animals with a diameter of less than one millimeter. These animals have greater surface area of volume ratio and have low rate of metabolism.
During evolution, as the animals became complex and complex and grew in their size, their skin or external body surface become impervious to water. Thus the gaseous exchange became impossible through diffusion. In large animals certain organs were developed for exchange of gases w.g. the moist vascular skin, gills, lungs and tracheoles. These large animals have developed blood vascular system which transports oxygen from the respiratory surface to the deep cells and tissues in all parts of the body. The blood in all animals has some respiratory pigments like haemoglobin which carry large amount of oxygen efficiently from respiratory surface to the interior cells.
Properties of a Respiratory Surface
1. Respiratory surface should have large surface area.
2. Respiratory surface should be moist.
3. Respiratory surface should be thin walled.
4. Respiratory surface should have blood supply.
Gaseous Exchange Through Skin
For the exchange of gases through the skin the skin must be moist and richly supplied with blood. The oxygen is diffused from the external water to the blood and the carbon dioxide is diffused from the blood to exterior water. In amphibia and fishes the gaseous exchange occurs through the skin besides through the gills or lungs. The frogs and tortoises breath through the skin during their hibernation period.
Gaseous Exchange by Gills
The gills are very effective for gaseous exchange in aquatic animals. Gills are of two types:
(a) External Gills
(b) Internal Gills
(a) External Gills
Some animals have external gills which project out of body of animals. These gills have very thin and highly vascularized surfaces e.g. the dermal papillae of star fish and arthropods.
(b) Internal Gills
These are present inside the body inner to skin e.g. in fishes and arthropods. Have you ever examined a fish closely? How ill you know that the fish is fresh or not? If the colour of gills is red then it is fresh but if the colour of gills is changed, it is definitely not fresh. The red colour of the fish gills shows the presence of oxygenated blood.
Gills of Fish
In fishes the gills are present in the branchial cavity present on lateral sides of the body behind the head. This branchial cavity is covered over by an operculum. There is a counter current flow of water and blood in gills which ensures maximum exchange of oxygen and carbon dioxide between the blood and the bathing water. Water enters through the mouth, flows over the gills and goes out of the body from the opercular aperture.
Human Respiratory System
In humans, there is very efficient respiratory system. It consists of certain organs which are called respiratory organs these include nose, pharynx, larynx, trachea, bronchi and bronchioles.
Nose
The air enters through the external nostrils into the nasal cavity. This is lined with mucous secreting epithelium and ciliated epithelium. The nostrils are lined with hairs. The nasal cavities, located above the oral cavity and behind the nose are covered with epithelial tissue.
The beating of cilia creates a current in the mucus that carries the trapped particles towards the back of the nasal cavity. From here the mucus drips into the throat and is swallowed. Mucus keeps the nasal cavities moist. Bones of the nose warm up the air. Mucus moistens the air. Hair filter the air and stop the dust particles bacteria and any other foreign substance from going to next part of respiratory system. In this way air is purified and is then pushed into the pharynx.
A number of cavities called sinuses open into the nasal cavity. The sinuses are lined with mucus secreting epithelium. The opening of sinuses into the nasal cavity is very narrow. If these openings are closed due to cold or inflammation, the sinuses get filled up with mucus this results in headache and changed voice.
Pharynx
The nasal cavity opens into the pharynx (throat) through two small apertures which are called internal nares or internal nostrils. The pharynx is muscular passage which extend from behind the nasal cavities to the opening of oesophagus and larynx. The air goes from the pharynx into the larynx.
Larynx
The upper most part of the wind pipe (trachea) is called the larynx. The larynx is a cartilaginous box. Two fibrous bands called vocal cords are located in this box. These vibrate to produce sound. Larynx is, also called sound box or voice box. The air enters the larynx through a small aperture called glottis which is guarded by a muscular flap called epiglotis which fits into this opening while the food is being swallowed into the oesophagus. It prevents the food from entering into the trachea and choking it. During breathing epiglottis keeps the glottis open so that air goes to trachea.
Trachea
The air tube (wind pipe) is known as trachea. It is about 12 cm long and lies in front of the oesophagus. It has incomplete C shaped cartilagenous rings which are regularly placed in its wall and all along its length. These rings prevent the collapsing of the tube nd thus keep the air passage wide open all the time. Trachea is also lined with ciliated mucous epithelium. Any foreign particles present in the inhaling air get trapped in the mucous that is moved out of the trachea by breathing of the cilia in the upward direction. In trachea air is further cleansed and filtered and then moved towards the lungs.
Bronchi
The trachea while passing the chest cavity divides into two smaller tubes which are called bronchi (single bronchus). Bronchi are similar in structure to the trachea but are smaller in diameter and they have in their walls small irregular catilageuous plates. Each bronchus enters into the lungs of its own side. The right bronchus divides into three secondary bronchi and the left bronchus divides into two secondary bronchi which serve the 3 right and 2 left lobes of the lungs respectively.
Bronchioles
the secondary bronchi further divide into very fine branches until they end in thousands of passage ways called respiratory bronchioles. The bronchioles have not cartilaginous plates in their walls. They have smooth muscle and elastic fibers.
Alveoli
The walls of the respiratory bronchioles have clusters of tiny branches(like bunches of grapes) that along with the respiratory bronchioles re the sites of gaseous exchange, these pouches or air sacs are called alveoli (singular: alveolus). The alveoli are enormous in number. Each lung has about three hundred million alveoli.
Pulmonary artery brings deoxygenated blood from the heart into the lung. Here, it divides and re-divides until it forms a network of fine capillaries over the wall of each alveolus. The walls of alveoli are very thin (1/1000 mm thick) and moist. Thus, alveoli are efficient site for gaseous exchange.
The Lungs
There is a pair of lungs present in the chest in man. Actually, the masses of alveoli constitute lungs and their lobes. The lungs re protected by the chest box from sides and by a doem shaped muscular diaphragm from below. Chest box or ribcage is made up of ribs. Between the ribs, there are present inter-costal muscles. The diaphragm is a muscular sheet which partitions the chest and abdomen.
The two lungs re covered by a double layered membrane called pleural membrane. There is a thin film of fluid in between the two layers. This watery fluid makes the movements of the lungs (expansion and contraction) easy. It also protects the lungs from external injuries.
(Diagram)
Mechanism of Breathing
Breathing occurs in two phases:
1. Inspiration
2. Expiration
1. Inspiration
1. During inspiration, the dome-shaped diaphragm contracts and becomes flat some what and thereby lowering the floor of the thoracic cavity.
2. The external inter-costal muscles contract raising the ribcage. A combined action of these two events expands the thoracic cavity, which in turn expands the lungs.
3. The air pressure within the lungs decreases.
4. Thus air from the environment outside the body is pulled into the lungs to equalize the pressure of both sides.
2. Expiration
1. The diaphragm relaxes and assumes dome like shape. During expiration, the external inter-costal muscles relax and the internal inter-costal muscles contract as a result of which ribcage drops.
2. The combined action of these two event decreases the volume of the thoracic cavity which in turn decreases volume of lungs.
3. The air pressure with in the lungs increases.
4. The air is thus forced out of the lungs.
Bad Effects of Smoking on Heath
Smoking is injurious to human health. The smoke contains many chemical and gases. Dried tobacco leaves are used in cigarettes. The tobacco on burning produces a number of dangerous and toxic compounds.
Chemicals Present in Cigarette Smoke and Their Harmful Effects
(a) Nicotine
1. Man is addicted to cigarette damages brain tissues.
2. Causes blood to clot more easily.
3. Harden walls of arteries.
(b) Tar
1. Kills cells in air passages and in lungs.
2. Increases production of mucous and phlegm in lungs.
3. Causes lung cancer.
(c) Carbon Monoxide
Prevents red blood cells from combining with and transporting oxygen around the body.
(d) Carcinogens
promote the growth of cancerous cells in the body.
(e) Irritants
1. Irritate air passages and air sacs in the lungs.
2. Kill cells at the surface of air passages.
3. Causes smoker’s cough and lung cancer.
Combustion
A chemical reaction in which a substance combines with oxygen and produce heat, light and flame is called Combustion.
Respiration
A process that liberates chemical energy from organic molecules when oxidized is called Respiration. It occurs in all living cells. In fact respiration is a series of complex oxidation and reduction reactions in which energy is released bit by bit.
Photosynthesis
The process in green plants by which green plants manufacture their own food by using carbon dioxide and water with the help of energy absorbed by chlorophyll from sunlight is called photosynthesis.
Relation of Combustion, Respiration and Photosynthesis
Combustion is the process of burning in which wood, coal, methane, gas etc are burnt in the presence of oxygen, producing carbon dioxide and water accompanied with the release of energy. It is an exothermic chemical reaction.
Cellular respiration can be compared to burning of fuel in which organic food (carbohydrates, fats and proteins) rich in carbon burn in the presence of oxygen producing carbon dioxide, water and energy.
Respiration like combustion is a catabolic exothermic chemical process. However, the difference between the combustion and respiration is that the combustion takes place in one go, releasing the entire energy as the heat, which may be utilized or is lost into the environment. the respiration completes in several small steps. Each step is under the control of a specific enzyme, releasing energy in small amounts which can be stored in the form of ATPs. Photosynthesis, another metabolic process, is just opposite to combustion. Combustion is a catabolic process; the photosynthesis is an anabolic process. In photosynthesis organic substance is synthesized from carbon dioxide and water in the presence of sunlight energy and chlorophyll. The molecular oxygen is evolved as the by-product combustion is exothermic and releases energy, photosynthesis is endothermic and absorbed energy.
 Photosynthesis and respiration are the two metabolic reactions opposite to each other. Photosynthesis takes place only in the gree parts of the plant body having chlorophyll, whereas respiration takes place in all the living cells of plants and animals. Mitochondria are the cellular organelles where respiration takes place while the organelles for photosynthesis re chloroplasts. Photosynthesis takes place during the day time only, whereas respiration takes place day and night. In photosynthesis body weight is increased but in respiration weight is decreased. Respiration is an oxidation reaction whereas photosynthesis is a reduction reaction and can be well understood by comparing their chemical reactions.
Chemical Equation in Respiration
Glucose + Oxygen ——-> Carbon dioxide + Water + Energy (In presence of mitochondria and enzymes)
Chemical Equation In Photosynthesis
Carbon dioxide + Water ——–> Glucose + Oxygen (In presence of chloroplast and solar energy)
Respiratory Organs of Insects
The respiratory system of insects is called the Tracheal system. It is a network of interconnecting air filled tubes called trachea delivering air directly to the body tissue cells. Trachea open outside through pores called spiracles.
Each trachea has chitinous cuticle lining which prevents it from collapsing.
 A pair of spiracles is usually located on the sides of each segment of the thorax and abdomen. Spiracles have valves to open or close them regulated by special muscles. This controls water loss from internal body tissue.
Trachea break up into numerous smaller tubes called tracheoles which ramify among the body tissues ending blindly. Tracheoles lack a chitinous lining. At rest the tracheoles are filled with watery fluid through which gaseous exchange tkes place in dissolved state.
Ventilation is brought about by contraction and relaxation of abdominal muscles which result in a rhythmic pumping of air into and out of the trachea.
Gas exchange takes place in tracheoles which are permeable to gases and are filled with a fluid in contact with the body tissue. Since oxygen diffuses directly into the tissue cells, blood of insects does not have hemoglobin so it is white. However, removal of carbon dioxide is dependent on blood plasma which takes it up for removal via spiracles

FUNGI & ALGAE

Fungi
During rainy season, a large number of umbrella-shaped mushrooms emerge on dung-piles. Fluffy mass of tangled threads like structure with black-dots of molds is also often seen growing on orages and bread, these mushrooms and molds are fungi.
Characteristics of Fungi
1. Fungi are simple heterotrophic eukaryotes which cannot manufacture their food and have absorptive mode of nutrition (e.g. absorbed prepared food).
2. Cell wall is made up of Chitin instead of cellulose.
3. Some fungi are parasitic while others are saprotrophs.
4. Parasitic fungi obtain their food from other living organisms.
5. Saprotrophic fungi get their food from dead animals, plants, their wastes and decaying materials.
Economic Importance of Fungi
Fungi are useful as well as harmful to humans. e.g.
Useful Aspects of Fungi
Saprotrophic Fungi
Saprotrophic fungi chemically break down dead bodies of organisms and their wastes into simple components. They clean the environment and also cause the recycling of nutrients.
Mycorrhizal Fungi
Mycorrhizal fungi improve the growth production of crop plants.
Edible Fungi
Mushrooms and some other fungi are edible.
Antibiotics
Some antibiotics are also obtained from some fungi. For example, Penicillin, the first antibiotic discovered in 1928 by Alexander Flemming. Penicillin is obtained from the fungus penicillium.
Yeasts
Yeasts are used in making bread and alcohol.
Mushroom
1. During rainy season, a large number of umbrella like mushrooms emerge on dung piles.
2. Mycelium of mushroom is saprotrophic, spreading under group in the soil that contains, decaying and organic matter.
3. When spores are to be formed, many hyphae of mycelium come out of the soil to form umbrella shaped fruit bod, the familiar mushroom. It can be 3,4 inches in height.
4. Fruid body consists of two main parts; a lower stalk or stripe, and an upper umbrella shaped cap or pilens which bears annulus around it just below the cap.
5. On maturation, many radial plates or gills are seen on the underside of the cap on which enormous numbers of spores are produced.
6. Some mushrooms, like Agaricus, can be used as food before their fruit bodies become overripe. Agaricus is rich in protein. Some mushrooms, like Amanita, are deadly poisonous.
(Diagram)
Algae
Algae are a group of simple eukaryotes in which, like plants, chlorophyll is found. They are photosynthetic autotrophs and have cellulose in their cell wall. However unlike plants but ike fungi, their organs are unicellular and body is simple, thallus. Therefore they are placed in another kingdom, the Protista.
Algae, are mostly (found in water). A large number of algae are found in vast saltwater oceans. These are called marine algae, other are found in lakes, ponds, puddles, streams and rivers. These are called fresh water algae. Some marine algae, called the helps and grow as long as 60 meters or more in a season. Some of them are used as food.
Characteristics of Algae
1. All the algae have chlorophyll so they are autotrophic; they make their own food by photosynthesis.
2. Their cell walls are made up of cellulose.
3. Algae are mostly marine found in the sea. While others are found in fresh water lakes, ponds, puddles, streams and rivers and they are also found in damp soil.
4. Their plant body is called a thallus without a true root, stem or leaf.
5. Algae are sometimes classified on the basis of the pigments they contain. Their green colour can be masked by the presence of other pigments.
6. Their reserved food material is starch.
7. Algae have a wide variety from unicellular algae, e.g. chlamydomanas and spirogyra to multicellular large seaweeds like sargassum.
8. Previously algae were regarded as plants and were placed in thallophyta.
Chlamydomonas
It is fresh water green alga, commonly found in fresh pond and drains. It is single celled green algae which are seen only under a microscope.
Structure
1. Chlamydomonas is spherical, oval or pear-shaped.
2. The cell is enclosed by a cell wall which maintains its shape.
3. In the anterior part, the cell wall forms an outgrowth called apical papilla.
4. Two flagella (singular flagellum) arise from the cytomplasm below the apical papilla and come out through the cell wall. These help in swimming.
5. A thin cell membrane lies beneath the cell wall, it represents the ourter surface of cytoplasm.
6. In cytoplasm, there is, a cup shaped chloroplast, which is involved in production of food by process of photosynthesis.
7. The chloroplast contains, a spherical structure called pyrenoid in its posterior part, and a single red orange light-sensitive eye-spot on one side in its anterior regions.
8. The pyrenoid is supposed to store carbohydrates in the form of starch grains.
9. The eye spot helps chlamydomonas to determine its position nd direction according to changes in the intensity of light.
10. There are two contractile vacuoles near the base of flagella ‘which periodically expel excess water and waste from the cell.
11. A nucleus is present in the middle of chloroplast in the cytoplasm.
12. Although body, of chlamydomonas consists of a single cell, yet it performs all the basic functions of life. It reproduces both sex and asexual.
(Diagram)
Spirogyra
1. Spirogyra is a multicultural filamentous green alga. It is found in great abundance in fresh water ponds, lakes and streams. Its filamentous thallus consists of cylindrical cells.
2. These cells are joined end to end, to form un-branched filaments. Usually the filaments are found occurring in a large number.
3. The filaments are surrounded by a layer of mucilage that makes them slippery.
4. During day time, the oxygen produced during photosynthesis stores in the mucilage and the filaments start floating on the surface of water.
5. Each cell of Spirogyra is usually twice as long as broad.
6. The cell is surrounded by cellulosic cell wall. A peripheral layer of cytoplsm is present just inside the cell wall and around a large, central vacuole.
7. The vacuole is filled with cell sap.
8. A single nucleus is suspended near the vacuole by cytoplasmic strand.
9. The most prominent part of cell is its chloroplast. There may be one ore more than one chlrorplasts in each cell. The chloroplasts run along the; length of the cell in the form of spiral ribbon in the peripheral cytoplasm.
10. Numerous pyrenoids are located in a row in the chloroplast and are meant for storing starch. Spirogyra continually grows in length by cell division.
11. Each cell can be divide into two, so filament increases in length. The Spirogyra reproduces both sexually and asexually.