Life Sciences Questions and Answers – Endocrine System. This set of Life Sciences Multiple Choice Questions & Answers (MCQs) focuses on the “Endocrine System”.
1. Chemical messengers secreted by ductless glands are called___________
Explanation: Hormones are the chemical messengers which are secreted by the ductless glands called endocrine glands. These glands are controlled by the endocrine system.
2. Endocrine glands secret products into the ducts and transfer it into body cavities.
Explanation: Endocrine glands are called ductless glands. They secrete their products directly into the bloodstream and circulate in the body.
3. Which of the following is NOT an endocrine gland?
Explanation: All of them are endocrine glands except the hypothalamus. Hypothalamus and thymus are not classified as endocrine glands but are included in the endocrine system as they involve in the secretion of hormones.
4. Which of this statement is INCORRECT regarding the function of hormones?
a) Reproduction and sexual differentiation
b) Maintenance of internal environment
c) Maintain body temperature
d) Development and growth
Explanation: Hormones are released by specialized cells of the endocrine glands and act on distantly located target cells. A single hormone can contribute many functions and sometimes many hormones can perform a single function.
5. Mark the one, which is NOT the precursor of the hormone?
a) Amino acids
Explanation: Chemically, hormones can be divided into two categories, i.e., lipid-soluble and water-soluble hormones.
6. What is the precursor of steroid hormone?
Explanation: Cholesterol acts as a precursor of steroid hormone. DHEA is a natural steroid hormone that is synthesized from cholesterol.
7. Which of the is a fat soluble hormone?
a) Amine hormone
b) Peptide hormone
c) Thyroid hormone
d) Protein hormone
Explanation: Thyroid is a lipid-soluble hormone while amine, peptide, and protein hormones are water-soluble, ranging from size 3 to over 200 amino acids.
8. Name the hormone which is synthesized from histidine amino acid?
Explanation: Epinephrine, norepinephrine, and dopamine are amine hormones, which are synthesized by modifying the amino acid tyrosine.
9. Which of the following is protein hormone?
d) Antidiuretic hormone
Explanation: Insulin and human growth hormones are protein hormones while oxytocin and antidiuretic hormones are peptide hormones. TSH or thyroid-stimulating hormone has carbohydrates attached to the protein so it comes under glycoprotein hormone.
10. Name the gland, which releases Neurohormone.
Explanation: Neurohormone is those which change their function according to their requirements like they can be releasing hormones or inhibiting hormone.
11. Name the hormone which takes part in the release of FSH and LH from the anterior pituitary.
a) Growth hormone
Explanation: GnRH is a Gonadotropin-Releasing Hormone, which is responsible for the release of follicle-stimulating hormone (FSH), and luteinizing hormone (LH).
12. Which of the following is Growth hormone inhibiting hormone?
Explanation: Somatostatin works against the growth hormone (GHRH), so it is known as a growth-inhibiting hormone. It consists of two peptides of 14 and 28 amino acids and is released from neurosecretory nerves.
13. Mark the one, which is not inhibited by the effect of somatostatin.
Explanation: Dopamine is a prolactin inhibiting hormone (PIH), which inhibits the release of prolactin from the anterior pituitary. It also functions as a neurotransmitter.
14. Name the hormone, which is released by the posterior pituitary.
Explanation: Oxytocin and vasopressin are released by the posterior pituitary. Posterior pituitary does not synthesize hormones, but it can store and release these two hormones.