Mixed / Miscellaneous Topics MCQs

In eyes there is no counter current mechanism. Other options: Option B: Testes are kept cool by the heat exchange in a countercurrent manner between spermatic arteries and veins as it is necessary for normal spermatogenesis to occur as spermatogenesis occurs at lower temperature than interior of the body. Option C: Hyperosmolarity of renal medullary interstitium is established by counter current multiplier and urea recycling is maintained by countercurrent exchange in the Vasa recta. Option D: Counter current mechanism in the villi increases the blood flow in the villi by decreasing oxygen availability for local metabolic reactions of the gut.

Melotonin receptors are MT 1 and MT 2 receptors MT 1 - Promotes sleep MT 2 - Synchronize circadian rhythm Reference: Ganong, 25th edition page no.278

Adrenal steroid hormones are derived from cholesterol In the mitochondria, cholesterol is converted to pregnenolone by cholesterol desmolase, also called as side- chain cleavage enzyme Reference: Ganong, 25th edition page no.362

DHEA-S is the major adrenal sex steroid Reference: Ganong, 25th edition page no.366

Urea is only 50% resorbed Reference: Ganong, 25th edition page no.680

Erythropoietin is produced by Interstitial cells in the peritubular capillary bed Reference: Ganong, 25th edition page no.706

Most of the reactions in steroid hormone synthesis involve hydroxylation Reference: Ganong, 25th edition page no.352

11-hydroxylase is the enzyme that helps in formation of Cortisol Reference: Ganong, 25th edition/page no.352