Leaves of certain plants roll up on a hot sunny day. Explain by giving suitable reasons.

Write any two limitations of using a Ganong's Potometer to demonstrate the uptake of water.

Two well-watered, identical plants were placed in brightly lit rooms at different temperatures — one at 15°C and the other at 38°C. The plant in the warmer room showed wilting by the end of the day. (a) Which plant phenomenon resulted in the wilting of the leaves? (b) Mention the factor of the phenomenon that is being tested.

Assertion (A): A thick cuticle reduces transpiration by acting as a barrier. Reason (R): Desert plants have large, thin leaves for transpiration. (a) (A) is true and (R) is false (b) (A) is false and (R) is true (c) Both (A) and (R) are true and (R) is the correct explanation of (A). (d) Both (A) and (R) are true and (R) is not the correct explanation of (A).

Read the explanations given below and name the structures: (a) The canal through which the testes descend down into the scrotum just before the birth of a male baby. (b) The part of the brain that regulates the peristaltic movement of the alimentary canal. (c) A structure that collects the soundwaves and conducts them through the external auditory canal. (d) The point of attachment of two chromatids of a chromosome. (e) Regulation of the opening and closing of stomata.

Match the items in Column I with those in Column II: Column I Column II Leydig cells Lack of thyroxine in children Stoma 12 pairs Ova Testosterone Cranial nerve Diffusion of respiratory gases Cretinism Haploid cells 31 pairs Diploid cells

Arrange the following in a logical sequence: (a) Australopithecus, Cro-Magnon, Homo erectus, Neanderthal man. (b) Pupil, Aqueous humour, Retina, Vitreous humour. (c) Effector, Receptor, Motor neuron, Sensory neuron. (d) Loop of Henle, Distal convoluted tubule, Bowman’s Capsule, Proximal convoluted tubule. (e) Water vapour, Soil water, Leaves, Ascent of Sap.

Name the following: (a) The fully developed part of the ovary containing a mature ovum. (b) A waxy layer on the upper epidermis of leaves meant to reduce Transpiration. (c) The ear ossicle which opens into the oval window of Cochlea. (d) The physiological process which is the starting point of all food chains. (e) An insect which is a classic example of natural selection due to industrial melanism.

Arrange the terms in each group in the correct order. Write them in a logical sequence beginning with the term that is underlined. (a) Palisade cells, Cuticle, Upper epidermis, Spongy cells. (b) Hepatic portal vein, Stomach, Hepatic vein, Liver. (c) Cyton, Dendrites, Synaptic cleft, Axon endings. (d) Insulin release, High blood sugar, Lowers blood sugar, Stimulates glucose uptake from blood. (e) Sperm duct, Seminiferous tubule, Epididymis, Efferent ducts.

Name the following: (i) The organelle that forms the aster during cell division. (ii) A genetic disorder in which the blood does not clot. (iii) The permanent stoppage of menstruation in human females around the age of 45 years. (iv) The openings on the barks of trees through which transpiration occurs. (v) A gaseous plant hormone which promotes ripening of fruits.

Define the term Transpiration.

The paper used to demonstrate unequal transpiration in a dicot leaf is: (a) Filter paper (b) Litmus paper (c) Starch paper (d) Cobalt chloride paper