(A) is not correct but (R) is correct
Insulin and glucagon are peptide hormones with distinct target tissues and mechanisms, but the assertion-reason pairing here requires careful evaluation. The correct answer is (A) is correct but (R) is not correct.
Assertion (A) Analysis
Insulin acts on multiple tissues including liver (hepatocytes), skeletal muscle, and adipose tissue to promote glucose uptake and storage. Glucagon primarily targets the liver to stimulate glycogenolysis and gluconeogenesis. Thus, (A) is true: insulin has broader tissue targets.
Reason (R) Analysis
Insulin is a peptide hormone, water-soluble, and cannot freely pass through cell membranes; it binds surface receptors (insulin receptor tyrosine kinase). Glucagon similarly acts via membrane receptors. Lipid-soluble hormones (e.g., steroids like cortisol) diffuse across membranes, so (R) is false.
Option Breakdown
| Option |
Explanation |
| Both (A) and (R) correct; (R) explains (A) |
Incorrect: (R) false. |
| Both correct; (R) not explanation |
Incorrect: (R) false. |
| (A) correct; (R) not correct |
Correct: Matches analysis . |
| (A) not correct; (R) correct |
Incorrect: Both false. |
Insulin acts on multiple tissues glucagon comparison reveals key hormonal differences for glucose regulation, vital for NEET Life Sciences prep.
Insulin Target Tissues
Insulin primarily lowers blood glucose by acting on hepatocytes (glycogenesis), adipocytes (lipogenesis, GLUT4 translocation), and skeletal muscle (glucose uptake). This multi-tissue action contrasts with glucagon’s liver-centric effects.
Glucagon Target Tissues
Glucagon raises blood glucose mainly via liver receptors, triggering cAMP-mediated glycogen breakdown. Minimal direct action on muscle or fat makes its scope narrower than insulin.
Hormone Solubility Facts
Both insulin and glucagon are hydrophilic peptides binding extracellular receptors—no lipid solubility for membrane passage. Steroids alone diffuse intracellularly.
Assertion Reason MCQ Insight
In exams like GATE/NEET, such questions test solubility-mechanism links. Here, Assertion holds due to tissue diversity; Reason fails as insulin isn’t lipid-soluble.
