CBSE Guess > Papers > Question Papers > Class X > 2008 >Science > Science Theory Q. 26. Illustrate the following with the help of suitable diagrams : Ans. (i) Regeneration in Planaria : See Q.4 (S.A.T.), Chapter 8. [Page 86 Q. 27 (a) (i) Name the parts labelled A and B in the neuron drawn above. (b) Name the hormone secreted by thyroid. What is its function? Why is the use of iodised salt advisable? Ans. (a) (i) A → Dendrite, B → Axon (b) Hormone secreted by thyroid is thyroxin. Thyroxin regulates carbohydrate, protein and fat metabolism in the body so as to provide the best balance for growth. Iodised salt consists of Iodine. Iodine is essential for the synthesis of thyroxin. Incase Iodine is deficient in our diet there is a possibility that we might suffer from Goitre. Or (a) What are plant hormones? Give one example each of a plant hormone that (i) promotes growth (b) Name the parts labelled A, B and C in the diagram given below. Write one function of each part. Ans. (a) Plant hormones are the chemicals which are used for control and coordination in plants. (b) A → Pons. They take part in regulating respiration.
CBSE 2008 Question Papers Class X
|