Question

The given diagram represents the mechanism of action for two categories of hormones. Which of the following options correctly identifies the labels A to I?

• A. A-Steroid hormone, B-Receptor, C-Secondary messenger, D-Non-steroid hormone, E-Nucleus, F-Hormone-receptor complex, G-Genome, H-mRNA, I-Protein
• B. A-Non-steroid hormone, B-Receptor, C-Secondary messenger, D-Steroid hormone, E-Nucleus, F-Hormone-receptor complex, G-Genome, H-mRNA, I-Protein
• C. A-Steroid hormone, B-Receptor, C-Primary messenger, D-Non-steroid hormone, E-Nucleus, F-Hormone-receptor complex, G-Genome, H-mRNA, I-Protein
• D. A-Steroid hormone, B-Enzyme, C-Secondary messenger, D-Non-steroid hormone, E-Nucleus, F-Hormone-receptor complex, G-Genome, H-mRNA, I-Protein

Answer 1

The correct option is B A-Non-steroid hormone, B-Receptor, C-Secondary messenger, D-Steroid hormone, E-Nucleus, F-Hormone-receptor complex, G-Genome, H-mRNA, I-Protein

Hormones which interact with membrane-bound receptors normally do not enter the target cell but generate second messengers( cyclic AMP, IP${}_3$, etc) which in turn regulate cellular metabolism in figure a.

Hormones which interact with intracellular receptors (e.g. steroid hormones, iodothyronines etc.) mostly regulate gene expression or chromosome function by the interaction of hormone- receptor complex with the genome. cumulative biochemical actions result in physiological and developmental effects.

So, the correct answer is 'A- Non- steroid hormone, B-Receptor, C-Secondary messenger, D- Steroid hormone, E- Nucleus, F- Hormone-receptor complex, G- Genome, H-mRNA, I-Protein'.