Biology Notes

Molecular Motors Molecular motors :molecular motors that move proteins,organelles and other cell parts ( collectively cargo )to all parts of the cell are  100 to 500 KDA ATPases .  ==> Attach to their cargo at one end of the molecules and two microtubules are actin Polymers with the other end had. ==> Convert the energy of ATP into movement along the cytoskeleton . three super families of molecular motors Kinesin  It  is double headed molecule that moves its cargo towards the positive ends of microtubules and then bends its neck to other head. ==> Some can kinesin are associated with mitosis and meiosis. ==> Other kinesin perform different function movement Kargo to the negative end of microtubule . 2 Myosin  ==> Divided into 18 classes.  == The heads of the myosin bind to Actin and produce motion by bending the neck  regions or walking along microfilament one head after the other 3 Dynesin  ==> Have 2 heads move particle to negative end

Nucleus Robert BrownThe title of the discovery of the Nucleus goes to Robert Brown in 1831, it looks dark than the surrounding cytoplasm. the shape of nucleus may be spherical or irregular. it controls the life and activities of the cell,in animal it is present in centre of cell but in plant it is pushed towards a side due to large vacuole. the number of nucleus is different in different cell. mononucleate the cell have one nucleus.   Binoculeate :  Cell have two nuclei.   Multinucleate : The cell with more than two nuclei. The nucleus is visible only during the non dividing phase. Chemically the nucleus is composed of DNA,RNA and protein including enzymes.  nucleus is composed of four  parts 1 Nuclear membrane:  it separates the nuclear material from the cytoplasm,it is not a complete barrier, It contains pores called nuclear pores.over 3,000 nuclear pores are present in egg but erythrocyte have  only 3 to 4 pores. Certain substances pass like protein and mRNA

Cytoskeleton (Microtubules,Intermediate Filament,Microfilament Cytoskeleton : skeleton of cell maintain the structure of cell.  permits the cell to change shape and move. Cytoskeleton composed of microtubules,microfilaments and intermediate filaments. microtubules they are long  unbranched and slender structure. ==> Road inside cell for transportation.  Made up of two Globular protein,Alpha tubulin and  beta tubulin,they are involved in the formation and degeneration of spindle during cell division. = = > Several cell organelle are derived from microtubules,these organelles are cilia,flagella,basal bodies and Centriole. ==> They provide the tracks along with several different molecular moters move,transport vesicle, organelles such as secretary granules and mitochondria . ==> The anticancer paclitaxel  (taxol) binds to microtubules and make them so stable so that organelles can't move, mitotic spindle can't form and the cell die. ==>

Mitochondria   Mitochondria are very important organelles they are present only in Eukaryotic cell they are involved in manufacturing and supply of energy to the cell.mitochondria have the ability to form the energy rich compound ATP by oxidative phosphorylation.  mitochondria called powerhouse of cell, mitochondria are the centre of aerobic respiration. The size and number of Mitochondria is different in different cells. it is about 0.2 to 1.0 nanometre in diameter and about 10 micrometre long. each Eukaryotic cell may have hundreds to thousands  of Mitochondria. Structure Of Mitochondria: mitochondria are double membrane bounded organelles,the outer membrane is smooth and the inner membrane forms many infolding called Cristae . the inner Chamber of Mitochondria is called mitochondrial matrix ,the inner surface of cristae contains small Nobe like structure called F1 particles ,these particle are suspended inside the matrix. the Cristae increase the surface area for c

Plasma Membrane Plasma Membrane: Outer most layer in animal cell and second outer most layer in plant cell. It is also called plasma-lemma. Structure of plasma membrane was proposed by two scientists Singer and Nicolson in 1972,called fluid Mosaic Model. According to this model plasma membrane is composed of two layer of phospholipid,(phosphatidylcholine and phosphotidylethanolamine). Along these lipids proteins are also present. Each layer of phospholipid has two ends. 1. Hydrophobic end  uncharged tail end insoluble,it is nonpolar end, inner part these ends are present opposite  to each other. 2. hydrophilic end polar end (outer part) has charged,head end of the molecule contains  phosphate  portion and it is is relatively soluble in water. in these layers proteins are present in different manner. 1. extrinsic proteins  also called peripheral proteins these proteins are present along the surface of lipids they have loose attachment with membrane surface (stu

Advantages Of Animal Communication It helps in recognition of species,individuals,neighbors,castes,(social insects),family, and demes. 2. It facilitates courtship and mating between males and females of same species. 3. It prevents agonistic interaction and promotes the establishment of social status between memeber of same species. 4. It facilitates social animals in the evening or in the danger zone. 5. It accelerates coordination among hunting animals. 6. It plays crucial role during parental care. 7. It alerts members of same species in a social group through alarm calls.

Cold Blooded and Warm Blooded animals Cold Blooded            Cold Blooded do not regulate their internal body temperature they change their temperature to the change in outer environment's temperature. The process to maintain the temperature is called thermal homeostasis. The process of maintaining this temperature is called thermal homeostasis. They need less energy for maintaining their body temperature,so they need less amount of food. They produce resistivity against  microorganisms invading their body for causing disease,if happens,they lower the effect of infection by decreasing the body's temperature. Hibernation - Resting stage at the time of winters which can be for weeks or months. Aestivation Resting stage at the time of summer. The temperature of a body depends on the temperature of the external environment. Metabolic rates changes with the change in environment's temperature. Cold blooded are categorized in three types : Ectothermy

Excretion And Thermo regulation in plants Excretion in plants In excretion unwanted toxic material and nitrogenous waste are removed from the body. In plants the rate of catabolic processes is sloW so waste products are produced in less amount, and they are used again in their anabolic processes. ii) In plants the nitrogenous waste products are also used in the chemical processes, and not removed from the body. iii) Mostily carbohydrates, are used in metabolic processes, so CO2 and water produced. The substances which are produced in excess amount are: (A) Water (B) CO2 and Oz (C) lons Removal of Water Extra amount of water is removed from the body of plant by two methods: (i) Transpiration : When extra amount of water is removed from the body of plant in the form of vapours is called transpiration, And ittakes place through stomata of leaves. ii) Guttation In this process water is excreted from the body by hydathodes in the form of smal

Hydrophytes These plants grow in water,founds in ponds,streams or lacks.these plants mostly under water but in some plants leaves are above water. Characteristics. I) Soft body without cuticle. ii) Roots are absent (in some plants poorly present. iii) whole body may perform function of absorption of water. iv) upper leaves (above the water) contain stomata through which transpiration takes place. v) those plants which are present underwater contain hydathodes(opening without guard cells) for removal of water. Example: Hydrilla,lotus,Lilly plants Halophytes:                   These plants grow in marshy soil or salty soil.(near sea)(water extra,oxygen disappear,salts extra),these plants produced special roots in air to absorb oxygen,called respiratory rotes Characteristics: I) the amount of minerals in the soil is high and active transport occurs,roots absorb water from the soil. iii) salt glands are present in the leaves which help to excrete salt and water from t

What is homeostasis and what are the important aspect of homeostasis? Homeostasis (Homo=same stasis= condition) Homeostasis is the maintenance of the internal environment of the body. It has 3 aspects 1. Osmoregulation: Maintenance of water and solutes in the body. 2. Thermoregulation (Thermo =temperature) In thermoregulation temperature is regulated till suitable limit. 3.Excretion: (Removal) In excretion unwanted,nitrogenious waste and toxic material are removed from the body. F eed back system Many physiological processes take place in the body to maintain homeostasis, In homeostasis there is a check and balance system,which maintain the homeostasis, Called feedback system. Types of Feed Back System 1. Negative feed back This is opposite reaction due to any change in the body fluid,for example when we take more sugar in diet,so our glucose level increase and message is transferred toward the CNS,CNS analysis and transf

Solute and solvent Solute and Solvent are the a part of the answer where the dissolved matter in any solution or mixture is named because the solute, while the liquid or gas that dissolves another liquid, solid or gas is named because the solvent. A solution are often defined because the homogenous mixture of two or more substances. So during a solution, the substance which gets dissolved is solute, whereas solvent is that the substance during which the solute will dissolve. There are many products in day to day life prepared by the mixture of 1 or many solutes and solvents and form an answer . These products are medicines,tea, coffee, juice , etc. The homogenous mixture is that the solution during which the solutes dissolve completely and uniformly into the answer . While solubility is that the ability of the substance to dissolve into another substance. In this article, we'll discuss the difference and characteristics of the solute and solvent. BASIS FOR COMPARISON SOL

Methods to control Disease. Vaccination and immunization The dead germ (virus or bacteria) which are injected into the body and produce Anibodies and make the person immune from the attack of that germ is called vaacine and process of injecting vaccine into body is called vaccination The development of immunity in the body as a result of vaccination or live germ is called immunization  Edward Jenner  developed the technique of vaccination in 1795 Cowpox pus is known as vacca. Vacca is a Latin word It neans cow. The term Vaccination is derived from this word vacca. The vacca or pus contains killed germs Edward Jenner injected pus into the body of a person.the person developed immunity  against it. He became immune. the attack of live virus. The individuais are vaccinated at early life for sOme Diseases. They become immune to such disease throughout their life. Many diseases like polio, whooping,cough, measles, mumps etc are controlled by vaccination. Vaccine has

BIOLOGY AND ThE SERVICS OF MANKIND  It help in many ways like increasing the food level,controlling the disease and protecting  environment. FOOD PRODUCTION Food production  is increased by following process 1. The Scientists use the prinejples of genetics to improve the existing Varities of the crops and livestock and like wheat, rice, corn and chicken.  The techniques which are used to improve the varieties of the crops are given below. Genetic engineering:  The manipulation of genes is called genetic engineering. It can produce transgenic plants. The plants which have foreign DNA in their cells called transgenic plants. Cloning:  The production of the, genetically identical copies of the Cells or Organisms which are reproduced asexually  ars called cloning. Cloning can make multiple copies of desired genotype. Tissue culture: In this process  Tissue of plant ate reproduced,called tissue culture 2.Controlling plant pathogens and pests: Pl

Chromosomal theory of Heredity Chromosomes contain genes and transfer the hereditary characters into new gener- ation. The function of chromosomes was explained by a German scientist Karl Correns in 1900. He considered the chromosome, as vehicles for the knowledge of hereditary. Later on a theory was proposed about chromosomes, by an American scientist Walter Sutton in 1902. This theory is named chromosomal theory of hereditary. The details of this theory are as follows: (1) Hereditary material within the nucleus: In reproduction two cells, sperms and ova participate in fertilization. Both gametes have equal contribution within the process. The male gamete contains little cytoplasm. So it indicates that hereditary material is present within the nucleus. (ii) Segregation of chromosomes: The chromosomes show the method of segregation (separation) during meiosis. This segregation is analogous to the Mendel's experiments. (iii) Haploid and diploid bodies: In rep

Chromosomal Variations Sometime due to somee reasons some changes OCCur in the morphology and number of chromosomes.  These changes are Visible phenotypically . Such changes are known as chromosomal variation. Chromosomal variations are as followS: 1.Variation in chromosomal number 2.Variation in chromosomal morphology 1. Variation in chromosomal number: In all living organisms the number of chromosome remain constant, but sometimes the variation in the number of chromosomes is called ploidy. It is of two types a.Aneuploidy or Heteroploidy b.Euploidy a.Aneuploidy or heteroploidy: During cell division when chromosomes are transferred into daughter cells sometime a changes occurs in the number of chromosomes, it is called aneuploidy or heteroploidy. *It is a change in the number of chromosomes, which do not involve whole set of chromosome, the change occurs in paris of a set only. In this process the chromosome number becomes unusual and abnormal. *Cause for

Types of chromosomes on the basis of centromere The position and number of centromere may be variable According to the number of centromere, chromosomes are of following Types Centromere may be variable in different chromosomes. Acentric:   These are the chromosomes Witnout any centomere Monocentric : These chromosomes have one centromeree Dicentric:  These chromosomes have tw0 centromeres, Polycentric :  These chromosomes have more than two centromere. Types of chromosomes according to the position of centromere  ( Telocentric )  These are rod-shaped chromosomes these have  chromosomes at their proximal end. ii)Acrocentric:  These are also rod-shaped chromosomes but the centromere is between two chromatids in such a manner that one arm is short and another is long. iii)Sub-metacentric:  These are J or L-shaped chromosomes. In these. centromere is present in the centre in Such a manner that two unequal arms are formed. iv) Metacentric: These

Molecular,Chemical and ultar Structure Of chromosomes: Dupraw and Hans Ris proposed the theory about the molecular structure of chromosome, called Unistranded theory. According to this theory the chromosome consist of an elongated coiled fibre,called nucleo-protein fibre.in this fibre a double stranded DNA is present.The DNA is covered by histone and non histone proteins and RNA.the histone and non histone protein are equal in number. When in prophase stage,chromosome is treated with acetocaramine ,two distinct regions of chromosome are visible according to the amount of proteins,DNA And RNA. 1.Euchromatin regions 2 Heterochromatin regions 1.Euchromatin regions Closely packed and stains dark and transcriptionally active. 2.Heterochromatin Regions In 1928 Heitz The chromatin that is more densely packed and stained dark and inactive. Two types of Heterochromatin A Facultive Heterochromatin Some time condense some time uncondense. B.Constitutive Heterochromatin In suc

Bioelements The elements found in the living organisms are called bioelements. A living thing is composed of a living substance called protoplasm. Different substance that make up cell are collectively called protoplasm(water,electrolyte, protein,carbohydrate and lipid? There are 92 chemical elements only 16 elements are use in the chemical compounds in the living organisms.these 16 elements are called bioelements. The properties of these 16 elements are different from the element that are present in the non living. There are two types of bioelements 1.Major bioelements The elements present in larger quantity in the body are called major bioelements.these are only 6 bioelements.the form 99% body of human. Oxygen 65% Carbon 18% Hydrogen10% Nitrogen 3% Calcium 2% Phosphoorus 1% 2.Bioelements The elements found in the living organisms are called bioelements. A living thing is composed of a living substance called protoplasm. Different substance that make up cell are c

Levels of biological organizations The study of biology at different levels is called biological organizations. Biological level starts from the very basic level of sub-atomic and atomic particles to the organisms itself .After that community population and entire world are studied. 1 Atomic and sub atomic level All the living and non living organisms are made up of atoms.these atoms are composed of subatomic particles like proton electron and neutron. 2. Molecular level The atoms combine with each other to form molecules.molecules are formed by ionic or covalent bonds.most of the biological molecules contain hydrogen carbon Nitrogen,Phosphorus and sulphur.there are two types of biological may lecules A.Micromolecules They have low molecular weight.like CO2, H2O etc B.Macromolecules They have high molecular weight like starch,protein etc *Organic molecules Contain both carbon and hydrogen together are called organic molecules *inorganic molecules Without carbon and