Lakshita was studying endocrine system for her unit test

Lakshita was studying endocrine system for her unit test. She was confused how hormones produce their effects on the target tissue. She read many times but still did not understand the process. She asked the same to her neighbour Stuti, a biology teacher in a school. Stuti explained her about the hormone receptor complex through diagrams and flow charts.
(i) Name the two types of receptors.
(ii) Why do different hormones use different types of receptors?
(iii) What are second messengers? Give two examples?
(iv) What values reflects from Lakshita’s character?

(i) Two types of receptors are
(a) Membrane bound extracellular receptors.
(b) Intracellular receptors.
(ii) The hormones which cannot enter the target cell, need membrane bound (extracellular) receptors and the hormones which can enter the target cell, need intracellular (mostly nuclear) receptors.
(iii) Second messengers are those chemicals, which are generated in the target cells, by those hormones which con not enter the cells, to bring about the biochemical changes, e.g., inositol triphosphate (IP-J cyclic adenosine monophosphate (cAMP).
(iv) Lakshita is worried about her studies and has capability to understand things in a better and scientific way, she is an initiative taker.