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A, PGT in Zoology www. A, PGT in Zoology, www. What are the Symptoms of graft rejection. J, M, S, M11, S, M Skin rashes Fluid accumulation in spleen and enlargement Emaciation becoming thin , Diarrhoea, Hepatomegaly, Anaemia and general immune suppression, Damage in bile ducts, Increased bilirubin synthesis 2. Explain the structure of immunoglobulin with a diagram.

Skip to content. Physics — Power Point Study Material: Physics Offline 1 Mark Quiz Mr. Santhosh Kumar, GBHr. Shool, Mechari, Salem. Share this: Twitter Facebook.

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Coming soon. Stay Tuned! Graduation B. Sc Post Graduation M. Under Gaduate Course B. View All. Cloning cannot produce children like the children born to genetic mothers. Variations in traits are bound to appear. The longevity of the new born, disease tolerance capacity are some criteria to be considered. Cloned animals have also developed diseases like arthritis. Cloning also leads to wastage of egg cells.

Cloned animals may have health problems. They may die at a much earlier age and may have short life span. Write about Huntington's chorea M,S This is a fatal disease caused by an autosomal dominant gene in human. The onset of the disease is between 35 and 40 years of age. It is characterized by uncontrolled jerking of the body due to involuntary twitching of voluntary muscles.

It leads to progressive degeneration of the central nervous system accompanied by gradual mental and physical deterioration. Huntingtons disease was the first completely dominant human genetic disease to come to light. The affected gene is located on chromosome 4. Other characteristics of this disease are deterioration of intellectual faculty, depression, occasional hallucination and delusions and other psychological problems. This disease is incurable. For environmental management to reduce or abate the pollution load in soil or water.

In waste recycling to increase productivity. In plant breeding by the incorporation of useful genes In bringing pest resistance in agriculture crops. And in treatment of diseases by way of gene therapy etc.

Write a note on scope of Bio-informatics. J, M, S Helps to create an electronic database on genomes and protein sequences from single celled organisms to multicellular organisms. It provides techniques by which three- dimensional models of biomolecules could be understood along with their structure and function. It integrates mathematical, statistical and computational methods to analyse biological, biochemical and biophysical data.

It provides genome level data for understanding normal biological processes and explains the malfunctioning of genes leading to diagnosing of diseases and designing of new drugs. Mention the uses of recombinant DNA technology. M, M The understanding of structure of eukaryotic genes and their components. To synthesize certain vital life saving drugs, hormones and antibiotics eg. The genotypes of plants are altered. New transgenic plants which are resistant to diseases and pest attack have been produced.

Genetic defects in animals as well as human could be corrected through gene therapy. Genetically engineered bacteria are called superbugs. Superbugs can degrade several aromatic Hydrocarbons and clearing oil spills in the ocean.

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What are the uses of transgenic animals? M, M More efficient than their normal counterpart in feed assimilation.

Faster growth and hence achieve the marketable size sooner. Meat quality is good. They are resistant to certain diseases. They serve as bioreactors for obtaining valuable recombinant proteins and pharmaceuticals from their milk or urine or blood.

Give the symbolic representation of pedigree chart. What is Glowing coal? What are the uses of it? OR Explain the protein model and its uses.

J In proteomics, to delineate information about a protein at atomic and molecular levels, models are constructed. X-ray crystallography can give a skeleton model of a protein from its results on its atomic details. With atomic data, computers nowadays generate graphic images of the molecules on high-resolution screen.

Computer modeling of protein began as early as The computer-generated models depict not only the properties of amino acids in a protein but also help to understand the protein function. Computer graphic models is the Glowing coal Uses: Protein structure helps in understanding biomolecular arrangement in tissue or cellular architecture.

Protein structures, protein models and computer aided graphic models help to understand biological reactions mediated by enzymes proteins.

Graphic models provided by computers are valuable to predict which fragments of a medically important protein can be used to design drugs and vaccines. Proteomics also helps in chemical industries to manufacture drugs, various chemical compounds and enzymes.

Describe the karotyping of human chromosomes M The 23 pairs of chromosomes in human are classified into seven groups viz, A-G based on position of centromere. Group A: Group A includes 1, 2 and 3 chromosomes.

It includes the largest chromosomes. Metacentric with two equal arms. Group B: Group B includes 4 and 5 chromosomes. Submetacentric with two unequal arms. Group C: Group C includes 6,7,8,9,10,11,12 and X chromosomes.

This is the largest group Submetacentric with two unequal arms. The X chromosome resembles the chromosome 6 in this group. Group D: Group D includes 13,14 and 15 chromosomes. Acrocentric Group E: Group E includes 16,17 and 18 chromosomes. Meta or submetacentric. Group F: Group F includes 19 and 20 chromosomes. Group G: Group G includes 21, 22 and Y chromosomes.

Explain Dr Ian Wilmut's cloning mechanism. S Dr. Ian Wilmut has produced a cloned sheep called Dolly by nuclear transplantation method. To produce cloned sheep he took the udder cell which is a somatic cell with diploid number of chromosomes.

An egg cell was also removed from a donor sheep. The egg cell cannot grow into a new sheep on its own because it only has half a set of chromosomes n. The body cell cannot grow into a new sheep on its own because it is not a reproductive cell.

So udder cell nucleus 2n was removed. Similarly the egg cell nucleus n was also removed. The nucleus of the somatic cell Udder was injected into the enucleated egg. The egg after the nuclear transplantation comes to possess full set of chromosomes viz. The egg was then transplanted back into the uterus of the sheep from which it was removed. The egg also can be transplanted to a new surrogate mother for development.

The egg cell grew and developed into a sheep Dolly. This cloned sheep is genetically identical to the donor sheep, which donated the diploid nucleus of its somatic cell and not the sheep which donated the egg cell. It helps to know more about the diseases.

It helps to understand more about the fundamental biology and the thread of life, - the DNA. It paves the way for the medical and bio engineering applications. It helps to apply the biophysical and biotechnologicl principles to biological studies. In turn, it will help to design new drugs and new chemical compounds to be used in health and environmental management respectively. What is database? What are its types? S Database Creating database means a coherent collection of data with inherent meaning, used for future application.

Database is a general repository of voluminous information or records to be processed by a programme. Databases are broadly classified as 1. Generalized databases 2.

Specialized databases. Structural organisation of DNA, protein, carbohydrates are included under generalized databases. RNA databases are included under specialized data bases.

Generalized databases contain sequence database and structure databases. Sequence databases Sequence databases are the sequence records of either nucleotides or amino acids. The former is the nucleic acid databases and the latter are the protein sequence databases. Structure databases Structure databases are the individual records of macromolecular structures. The nucleic acid databases are again classified into 1. Primary databases 2. Primary databases Primary databases contain the data in their original form taken as such from the source eg.

Secondary databases Secondary databases also called as value added databases contain annotated data and information eg. Explain the protein model and its uses. One of the computer graphic models is the Glowing coal model. Explain the origin and conduction of heartbeat. J, J, J During pumping action of heart, the heart muscles cause rhythmic contraction and relaxation of the heart chambers in a specific sequence.

The rhythmic, sequential functioning of the cardiac chamber is maintained by 1. Purkinje fibres. The SA node situated in the upper, lateral wall of the right atrium is a small, flattened strip of muscle fibre that is 1. The fibres of the SA node are closely associated with the muscles of auricles.

SA node is capable of generating action potential that can travel throughout the auricles. The velocity of conduction is 0. The excitation from the SA node stimulates the AV node. The AV node in turn conducts the stimulus to bundle of His and Purkinje fibres.

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These myocardial fibres are found all over the wall of the ventricles. In the conduction of stimulus through the AV node and the fibrous system there is a delay in transmission.

Enumerate the steps involved in root canal treatment of tooth. M, J, M It is a modern dental procedure to save a tooth in which the pulp the living tissue within a tooth has died or become untreatably diseased, usually as a result of extensive dental caries. Steps involved in Root Canal Treatment 1 A hole is drilled into the crown to remove all material from the pulp chamber. The root canals are then cleaned with fine-tipped instruments.

The procedure is usually monitored by X-rays. Some days later, the filling is removed and the canals are checked for sterlity. The mouth of cavity is then sealed with cement. Explain the different types of bone fracture. S, J, M 1. Green stick fracture: This fracture break is incomplete leaving one side of the cortex intact.

Closed fracture: Open fracture: It is a serious injury through which infectious germs may enter into the body. Pathological fracture: It may be due to hyperparathyroidism. Stress fracture: Birth fracture: Write down the various types of memory.

M, J The term memory denotes a specific brain function of storing and retrieving of informations related to experiences. The duration of memory varies from few seconds or hours, to several years. Types of memory: Sensory memory: This is the initial stage of memory process. Primary memory: The information in this memory is instantaneously made available so that a person need not search through his or her mind for it.

Secondary memory: This is also called long-term memory, fixed memory or permanent memory.

Explain briefly right and left brain concept. S In the cerebral cortex, the left hemisphere is connected to the skin receptors in the right half of the body. It also controls the muscles on the right side of the body. The right hemisphere is connected to the sensory receptors on the left half of the body. Further, it controls muscles on the left side. Both the hemispheres are also connected to the eyes. The sensory nerve tracts of the left eye is connected to the right hemisphere and the right eye to the left hemisphere through the optic chiasma.

Thus the left half sees the right half of the world while the right half sees only the left half of the world.

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The left and right hemispheres exchange information through a set of axons called the corpus callosum, and also through anterior commissure and hippocampal commissure. The two hemispheres have their own specific functions and the above division of functions or labour between the two hemisphere is called lateralization. The corpus callosum enables the right and left half of the brain to operate cooperatively, instead of independently. The anterior commissure plays an important role in unifying the emotional responses of two sides of brain.

Damage to the corpus callosum blocks the exchange of information between the two hemispheres. The left brain is concerned with language, number skills, reasoning, spoken language, scientific skills and right hand control. The right brain is concerned with art awareness, imagination, visual functions, emotions, music awareness, 3D forms and left hand controls.

The left brain is meant for analytical tasks while the right brain is for creative tasks. Draw the V. S of Human eye and label th parts. M 7. Enumerate the functions of skin M 1. Skin forms an effective barrier against infection by microbes.

It prevents dehydration and provides defense against chemical, osmotic, thermal and photic damage. It limits and regulates heat loss. It provides a major sensory surface with a range of receptors. It has limited excretory and absorptive functions. Skin also helps in the formation of vitamin D. Describe the mechanism of blood clotting. J When a blood vessel is damaged, it results in coagulation or clotting of blood.

A blood clot is a network of thread like protein fibers, called fibrin, that traps blood cells, platelets and fluid. The clotting depends on several proteins in the plasma. They are called coagulation factors. Normally these factors are in an inactive state. After injury they are activated to produce a clot. The activation can happen in three stages. Stage 1 - Formation of thrombokinase Damaged tissues release a mixture of lipoproteins and phospholipids called tissue factor TF or thromboplastin.

This factor in the presence of certain factors in the blood form a complex called prothrombinase or thrombokinase. Stage 2 - Formation of thrombin During this stage soluble plasma protein prothrombin is converted into the enzyme thrombin by prothrombinase. Prothrombin synthesis in liver requires vitamin K.

Prothrombin thrombin Stage 3 - Formation of fibrin The soluble plasma protein fibrinogen is converted to insoluble protein, fibrin by thrombin fibrinogen thrombin fibrin The fibrin forms the fibrous network of the clot. Adrenalin stimulates constriction of blood vessels supplying the intestine,kidneys, viscera and skin and causes dilation of blood vessels supplying skeletal and heart muscle.

It increases the rate, amplitude and frequency of the heart beat. It causes relaxation of the smooth muscles of the digestive tract and brings peristalsis to a halt 4.

It causes relaxation of the bronchi, dilation of the pupil, closure of sphincters and increases sweating 5. It causes contraction of muscles associated with hair follicles and makes the hair stand on end and causes goose flesh 6. It accelerates respiration and stimulates mental alertness 7. It stimulates the breakdown of glycogen to glucose, thereby increasing oxygen consumption and heat production. Biochemically it releases the free fatty acids and increases blood glucose level.

Adrenalin prepares an individual during emergency or stress situations. Hence it is called the fight, flight and fright hormone. Explain the eye defects-short sight and long sight. Light rays entering the eye are refracted more than is necessary.

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Consequently light is focused in front of the retina. The image perceived is thus blurred. The condition is called short-sightedness as objects near the eye are clearer than those further away. Myopia can be corrected by placing a concave lens in front of the eye.

The surface of the concave lens refracts light rays in such a way that the rays diverge slightly from their original path. The lens of the myopic eye now refracts the diverged light rays in to focus on the retina. Hypermetropia Long Sightedness b.

Hypermetropia Long Sightedness Hypermetropia results when the curvature of the eye lens is not great enough. Light rays are not refracted enough and would thus be focused behind the retina. The condition is called long-sightedness because distant objects are clearer than near ones. This happens because light rays from distant objects require less refraction than rays from near objects.

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Correction of hypermetropia requires placing a convex lens in front of the eye. The lens converges light rays before they enter the eye so that the eyes focuses the light correctly on the retina. Describe the process of absorption and assimilation of digested food. M As a result of digestion, all macromolecules of food are converted into their corresponding monomeric units.

Carbohydrates are broken into monosaccharides such as glucose and fructose. Proteins are hydrolysed into amino acids. Lipids get broken into glycerol and fatty acids. The simpler organic molecules along with minerals, vitamins and water enter into body fluids through the villi. The villi are small microscopic finger-like projections.

Each villus is an absorbing unit consisting of a lacteal duct in the middle surrounded by fine network of blood capillaries. While the fatty acids are absorbed by the lymph duct, other materials are absorbed either actively or passively by the capillaries of the villi. From the lumen of the alimentary canal absorbed food materials are carried to the liver through hepatic portal vein. From the liver, materials are transported to all other regions of the body for utilisation.

This conversion of food into energy and cellular organisation is called as assimilation. Give an account of cerebrospinal fluid and its functions.

J The ventricle of the brain and the central canal of the spinal cord contain, a clear fluid similar to plasma called cerebrospinal fluid CSF. CSF is formed by a group of cells called the choroid plexus located inside the four ventricles. CSF cushions the brain against mechanical shock when the head moves.

It acts as a protective covering for the CNS and confers buoyancy to brain. The CSF also provides a reservoir of hormones and nutrition for the brain and spinal cord. It acts as a mechanical buffer. Remaining inside and outside the CNS, it equalizes the mechanical pressure. If the intracranial pressure tends to rise the CSF is pressured out.

If the pressure tends to fall, more CSF is retained. Explain the mechanism of healing of fractured bone. S It involves three phases, viz. Inflammatory phase 2. Reparative phase 3. Remodelling phase. Inflammatory Phase: This blood clots to form a haematoma. This process takes place in one to two days. The soft tissue of this region undergoes inflammation. Repairative Phase: It bridges the gap and establishes contact between the ends of fractured bone.

The callus is nothing but granulation of tissues around the site of fracture. This phase takes place about eight to twelve weeks. Remodelling phase: This remodeling takes up to one year. Sleep is a state of unconsciousness. Substantiate the statement. M Sleep is defined as a state of unconsciousness from which a person can be aroused by appropriate sensory or other stimuli.

Types of sleep: They are 1 Slow wave sleep 2 REM sleep. Slow wave sleep: Though this sleep is frequently called dreamless sleep, dreams actually occur very often and even nightmares occur during this sleep. During this sleep the process of consolidation of the dreams in memory does not occur. This sleep is highly useful in decreasing blood pressure, respiratory rate and basal metabolic rate. REM sleep or Rapid eye movement sleep: It is usually associated with active dreaming.

The muscle tone throughout the body is exceedingly depressed during this sleepindicating strong inhibition of the spinal projections from the reticularformation of the brain stem. Enumerate neuro hypophysial hormones.