Anas Zoology

An important tool of molecular biology is DNA fingerprinting. It is a way to distinguish individuals as it is unique for every living being (except clones) and cannot be altered by any process. All segments of DNA do not code for protein. Some segments have regulatory function, others are Introns (Interviewing sequence/IVS) still others are repetitive DNA sequences/Mini satellite sequences . The most important segment for DNA fingerprinting are short repetitive nucleotide sequences which vary from person to person. These are also called Variable number tendem repeats (VNTR). To prepare a DNA fingerprint a small amount of saliva/blood/hair/semen or any other cell of the body is required. Steps of DNA fingerprinting are as follows: Extract the DNA from the sample. If DNA is not sufficient, amplify it using PCR i.e. make more copies of DNA using PCR. Cut DNA with restriction endonucleases. The cut segments possess DNA of different length in different individuals called restriction length

 The organisms whose cells contain a membrane bound nucleus and membrane bound organelles are called a eukaryotes. Structure of Eukaryotic Cell Characteristics of Eukaryotic Cell: Cell size and volume depend on the activities performed by it (5 - 100 μm). Cellulosic cell wall is present only in plant cells. Capsule is absent. Mesosome is absent. Well organized nucleus is present. Mononucleate condition is more common. DNA is linear and is covered by histonic protein (except in mitochondria and plastid). Monocistronic DNA is more common. Three kinds of RNA polymerase are present. One for each - rRNA, mRNA, tRNA. Transcription occurs in the nucleus and translation in the cytoplasm. Extranuclear chromosome are absent. Ribosome is 80S (60S + 40S). Protein synthesis is inhibited by cyclohexamide. All organelles are present. Cilia and flagella show characteristic 9+2 arrangement of microtubule and are made up of protein tubulin. Microfilaments are present. True sap vacuoles are common in pla

A prokaryote is a single celled organism that lacks a true nucleus and other membrane bound organelles. Structure of Prokaryotic Cell Characteristics of Prokaryotic Cells:  Cell is small in size (0.1 - 5 micrometers). Cell wall is made up of muramic acid (amino acid derivative of peptidoglycan). In many cells mucopolysaccharide capsule is present. Mesosomes controls cellular respiration and cell division. An organised nucleus is absent. DNA is circular and naked. Usually polycistronic DNA is present. Only one kind of RNA polymerase is present. Transcription and translation both occurs in the cytoplasm. Extracellular chromosomes are present in the form of plasmid or episome. Ribosome id 70S (50S + 30S) Cytoplasm lack cell organelles. If flagella is present, it is made up of single stranded protein called flagellin. Microfilaments - Actin and myosin are absent. Sap vacuoles are absent instead they have gas vacuoles. Endocytosis and exocytosis are absent. They divide by amitosis or simple

  What is Mutualism ? It is a positive relationship between two individuals of species where both the species are benefited. Examples of Mutualism: Pollination by Animals: animals like bees. butterflies and moths derive their food from plants and brings about the pollination of plants. Ants feed on honeydew produced as a waste product by aphids and in return offer them protection. Oxpecker feeds on ticks and blood-sucking flies from the body of large grazing mammals like zebras, buffalos, rhinos etc. This helps the large mammals from getting infected by such parasites and in return oxpecker's gets an easy meal. Oxpecker and Buffalo (Image taken from: https://www.youtube.com/watch?v=5MfrsKJailo)

What is Commensalism ? Commensalism is a positive interaction and a symbiotic relationship between two species in which one species benefits and the other neither benefits nor is harmed. Three terms are used to describe different types of commensalism Inquilinism: When one species uses other species for shelter. Example: Woodpecker drilling a hole in cactus to use it as a nesting site. The cactus is unaffected while the woodpecker is benefited. Phoresy: Occurs when one organism uses a second organism for transportation. Example: The Bromeliad treefrog carry ostracods from one bromeliad plant to another. Metabiosis: Occurs when one organism uses something produced by the first, usually after its death. Example: Hermit crab using the shell of a dead gastropod for protection. Other examples of Commensalism: Vultures feeds on the leftovers of kills of carnivores and other dead animals. It is a type of commensalism since vultures benefits without affecting the dead animals. The fish remora

  What is Parasitism ? Parasitism is a type of relationship between species in which one organism is benefited while the other organism is harmed. The organism that is benefited is called as parasite and the one that is harmed is called as host. Types of Parasite: On the basis of size parasites are classified into two types: Microparasite: They are characterized by their small size. Microparasite include bacteria, viruses and protozoans. Macroparasite: They are relatively larger as compared to microparasite. Macroparasite include flatworms, ticks, roundworms, fleas, lice and flukes. Parasites are classified into two types depending on where they live Ectoparasite: The parasites that live on the surface of the host are termed as ectoparasites. Mite, flea, ticks, lice etc are ectoparasites. Tick (an ectoparasite) Endoparasite: The parasites that live inside the body of the host are termed as endoparasites. Plasmodium, amoeba, roundworms etc are endoparasites. Roundworm (an endoparasite)

Matter is composed of very small particles known as atoms. Atom consist of a positively charged charged nucleus in the centre. The nucleus is surrounded by negatively charged electrons. The electrons are held around the nucleus due to the electrostatic attraction. The nucleus consist of two types of sub-atomic particles known as protons and neutrons. Protons are positively charged, neutrons do not bear any charge and are neutral. Proton is the reason the nucleus is positively charged. The number of electrons in an atom is equal to the number of protons. Fig 1. represents the structure of atom. Fig 1. Structure of Atom Proton is the subatomic particle with a positive charge. The mass of proton is 1.6726 X 10 -27 kilograms. The mass of proton is less than that of neutron. Neutrons are without any electric charge, hence they are termed as neutral. The mass of neutron is 1.6749 X 10 -27 kilograms. They keep the nucleus of an atom intact or stable. If there are too many neutrons in an ato

  What is Allelopathy ? Allelopathy is a biological phenomenon in which an organism releases chemicals which have positive or negative effects on other organism. The biochemicals produced by these organisms are known as allelochemicals. Examples: The River Tamarind contains toxic amino acid that inhibits other plants growth but not its own species growth. The leaf litter of some Eucalyptus species is allelopathic to certain microbes and plant species. The algae Chlorella vulgaris produces a toxin called chlorellin which is toxic to other algal species and bacteria.

  What is Amensalism ? Amensalism is association between two species, in which one species is harmed and other species is unaffected.  Examples: The mould penicillium creates a substance known a penicillin, this is extremely toxic to bacteria. The mould is unaffected but the bacteria dies. The black walnut secretes a chemical from its roots known as juglone, this harms the neighbouring plants, the black walnut is unaffected.

  What is Neutralism? Neutralism is a type of symbiotic relationship in which two different species are not affected by association with one another. (Both the populations do not affect each other) The term Neutralism was introduce by Eugene Odum an American biologist Examples: 1) Grass Carp and Catla residing on the surface of a pond do not affect one another as their food habits are different. Grass Carp feeds on macro vegetation while Catla feeds on zooplanktons. Grass Carp Catla                        

Mineral : Mineral is any substance which is required by plants for physiological functioning and it is mostly taken from the soil. What are Essential Elements ? Any element that is important for a physiological role in plant and the absence of this element prevents the plant from completing its life cycle is an essential element. According to Arnon and Stout three criteria must be met for an element to be considered essential, these are: A plant must be unable to complete its life cycle in the absence of the essential element. The function of the essential element cannot be replaced by another element i.e. deficiency of any one element cannot be met by supplying other element. The essential element must be directly involved in plant metabolism. Essential elements are divided into two categories : Macroelements and Microelements Macroelements: The mineral/element is required in large quantity, conc > 1ppm. Also known as major elements. Macroelements consists of Phosphorous (P), Potas