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 Heptanes: Heptanes are the smallest molecules which by itself cannot stimulate the production of antibodies but it combines with other chemicals and acts as Antigens and stimulates Immunogenecity. Hence heptanes are also known as Partial Antigens or Incomplete Antigens. Heptanes are less than 10,000 daltons range and probably cannot initiate Immunogenecity. Hence these have to combine with other molecules to act as an Antigen. When the heptanes bind covalently with large protein molecules and they become immunogenic. These large protein molecules are called as Carriers. For Example: Dinitro phenol (DNP) combines with Bovine serum albumin and acts as an Antigen.

General Characteristics   : Mycoplasma is a form of bacteria which was stidied by Nocard and Roux in 1998. Nowork named ita s Mycoplasma like organism. These are also called as Pleuropneumonia like organisms. Mycoplasma lacks celk wall and so have no shape i.e. pleomorphic in nature. Hence they are called as ''Jokers in the microbiological pack''. They were first isolated from Bovine sheep suffering from pleuropneumonia. The human infertility and abortions are now known to be due to mycoplasma infections in the urinogenetical tract. Many plant diseases eg., Aster yellow, Potato witches broom and Dwarg disease of mulberry are due to mycoplasma. In 1966, International Committee of Nomenclature of Bacteria, recognised Mycoplasma, as different form of bacteria and placed them under a seperate class-Molicutes which consists of two genera-Mycoplasma and Acholeplasm. It has no cell wall, A three layered Plasma membrane is present as outer covering. These are unicellular, non...

AUXINS:  Darwin performed some experiments on canary grass. In his experiments, when the coleoptile of grass was unilaterally illuminated, it curved towards the source of light. The experiments done by him confirms some interations  between the tip and light and light resulting in curvature of tip.     Went removed the tip of avena coleoptile and placed it on agar-agar block for a measured length of time and it produces a positive curvature. He named this substance as Auxin. Isolation of Auxin Kosland Hargen-Smith isolated Auxin-A from human urine. Kogl, Erxlaben and Hargen- smith isolated Auxin-B from corn germ oil. It was chemically identified as Indole-3 Acetic Acid(IAA). Biosynthesis of Auxins Thimann 1935 observed the fungus Rhizopus Suinus can convert the amino acid Tryptophan into IAA. Transport: Auxins occurs in the meristems. It is transported polarly and movement is basipetal. Physiological effects: Induces cell elongation...

Growth in plants: Growth is irreversible and permenant increase in size of cell or tissue or organ or entire plant body. It is always accompained by metabolic associated reactions. Growth in plants is indeterminate and grows till death due to the activity of meristems in plants. Growth can be measured by increase in protoplasmic content, fresh weight, dry weight, length, area, volume and number of cells.  Phases of growth: In plants growtg and development each cell undergoes three phases. 1. Meristematic phase:       In this phase meristematic cells divides continuously. The cells are active and this phase is also called as Cell-division Phase. 2. Elongation phase:        The cells which are formed in meristematic phase becomes enlarged in thier size and forms vacoules at the centre of the cell. 3. Maturation phase:          The cells are matured and differentiated into tissues to perform spe...

POLLINATION: In a simple words pollination us the transfer of pollen grains from anther lobe to the stigma of gyneocium. Types of pollination: Two types of pollination has been observed. They are. 1. Cleistogamy 2. Chasmogamy Cleistogamy: Pollination that occurs in unopened flowers is called Cleistogamy. Ex. Sereteocarpus. Chasmogamy: Pollination that occurs in opened flowers is called Chasmogamy. There are two types in this type. They are. 1. Self pollination or Autogamy. 2. Cross pollination. 1.Autogamy or Self Pollination.  The transfer of pollen grains from the anther to the stigma of same flower is called Autogamy or Self Pollination. 2. Cross-Pollination.  Teansfer of pollen grains from anther to the stigma of another flower is known as cross pollination. It is again of two types. Geitonogamy.  xenogamy. Geitonogamy:  It is the transfer of pollen grains from anther to the stigma of another flower of sa...

Cyanobacteria General characters: Also called as Blue-green algae. Found in water and other wet places. These are oxygenic photosynthetic, prokaryotic and gram negative bacteria. The outer layer of cell wall is made of lipo-polysaccharides and inner layer is having peptidoglycon. Ribosomes, thylakoids and phycobilosomes are present in cytoplasm. Ribosomes are 70s type, thylakoids contains phycobilosomes which has photosynthetic pigments like phycocyanin, phycoerythrin and small amount of protein. Reserve food material is cyanophycin granules, starch, glycogen, phosphate granules. Gas filled vacoules helps the bacteria to float on the surface of water.  Vegetative reproduction is by fission, fragmentation and by locomotion harmagonia. Asexual reproduction is byformation of akinites, endospores, exospores and nanocytes. Thallus organisation in cyanobacteria: Thallus organisation in the sense no differntiation of organism into different parts. It is in  thr...

Lichens: The symbiotic assosiation between fungi and algae resulting in a plant body is called lichens. Plant body of lichen thallus is irregular and made up of algal component i.e. phycobiont and fungal component i,e. Mycobiont. Differnt forms of lichens: 1. Crustose lichen:     These are flat, thin, crust like thallus appeared partly or completely embedded into the substratum.  Ex. Rhizocarpa graphis. 2. Foliase lichens:    These are flat, leaf like lobed thallus attach to the substratum with the help of rhizoids.  Ex. Permeria. 3. Fruticose lichens:     These are brush like hanging cylindrical or spherical shape. Attached to substratum with the help of basal mucilage disk.      Ex. Cladonia. Internal morphology of lichen thallus:    It shows mainly four zones. They are:            1. Upper cortical zone            2. Algal zo...