Long Answer Type(a) Describe the structure of arteries, veins and capillaries. Explain the way in which each of these is adapted for its function.
(b) Give an account of the ‘Mass Flow Hypothesis’ for translocation of solutes.
(c) Give the meaning of the following:
(i) Digestion (ii) Assimilation
(a) Give a schematic representation of non-cyclic photophosphorylation showing both the photosystem.
(b) Describe the structure of a myofibril of a striated muscle.
(c) Give four points to show the importance of vegetative propagation.
(a) Describe the mechanism of inspiration and expiration in man.
(b) Draw a labelled diagram of the vertical section of the human eye.
(c) (i) What is Ageing?
(ii) Give two functions of the amniotic fluid.
(a)
(i) Draw a labelled diagram of chloroplast as seen under an electron microscope.
(ii) Name the three major photosynthetic pigments.
(b) Describe the events that take place between pollination and fertilisation in plant.
(c) Name the hormones associated with the following :
(i) The only gaseous plant regulator.
(ii) A growth inhibitor in plants.
(iii) Resorption of water from the urine in the distil convoluted tubule.
(iv) Rise in blood calcium.
(a) Explain the DDT resistance of mosquitoes to the pesticide.
(b) What are the symptoms of Diabetes mellitus?
(c) Define :
(i) Gene pool
(ii) Genetic Erosion.
(a) Write short notes on:
(i) DNA finger printing
(ii) Cryopreservation
(iii) Hemophilia
(iv) Green manure.
(b) What are the activities of Community Health Services.
(c) Give the differences between B cells and T cells.
(i) DNA Finger Printing: It is a technique which is used to ascertain relationships and the identity of a person as DNA patterns are unique to each individual. Nowadays, DNA fingerprinting has become a very useful technique in forensic science to reach at correct decisions. It is also called as DNA typing or DNA profiling.
(ii) Cryopreservation: The preservation of germplasm at ultra-low temperatures (at about -190°C) is called cryopreservation. It is a useful technique for the preservation of cultured animal cells, spermatozoa, embryonic tissues etc. because all biological activities cease at very low temperature.
(iii) Haemophilia: It is a sex-linked hereditary disease which is more common in men than in women. It is also known as bleeder’s disease. The person suffering from this disease lacks in normal clotting of blood so that even minor injuries can cause continuous bleeding that may lead to the death of the person due to haemorhage. It is X-linked hereditary disease that is why it is more common in men than in women.
(iv) Green Manure : The crops which are grown, ploughed under and mixed with soil to improve soil fertility and the productivity are called green manure. This is similar to farmyard manure and increases the humus content of the soil. It also adds nitrogen to the soil. It is a cheap and non-polluting manure. Both leguminous and non-leguminous crops are used as green manure. Crops such as Sunhemp, clover, berseem, cowpea, dhaincha, etc. are used for green manuring.
(b) Activities of community Health Services : The main services rendered by the community health services are as follows :
1. Maintenance of sanitation by providing pure and safe drinking water and proper disposal of sewage.
2. Providing assistance and facilities to prevent and control various communicable diseases.
3. Arranging for vaccination campaigns, identifying and isolating diseased person and providing them proper treatment.
4. Providing maternity and child care services.
5. Educating people about community health, nutrition and family welfare.
(c)
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B-Cells |
T-Cells |
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1. B-cells provide hormonal or antibody-mediated immunity. 2. These are formed in the bone marrow. 3. They release antibodies produced into the lymph which enter the blood circulation. 4. The antibodies attack the foreign particles and destroy them. 5. They do not react against the cancerous tissue and transplants. |
1. T-cells provide cell-mediated immunity. 2. These are formed in the thymus gland. 3. They do not release antibodies but hold onto the antibodies. 4. The whole cells directly attacks the foreign particles and destroys them. 5. They also react against the cancerous tissues and the transplants. |
(a) Describe Lederberg’s Replica Plating experiment to show the genetic basis of adaptation.
(b) Give an account of chromosomal aberrations (mutations).
(c) What is a pacemaker?
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