Which gland produces the hormone melatonin? MCQ with Answer and Explanation

Explanation:
The SA node, located in the right atrium, spontaneously generates electrical impulses, setting the heart rate. It is the natural pacemaker. The AV node delays the impulse before it reaches the ventricles.

Explanation:
Nepenthes (pitcher plant) is an insectivorous plant that traps insects in its modified leaf pitchers to supplement nitrogen in nutrient-poor soils. Cuscuta is parasitic, Loranthus partial parasite, Monotropa saprophytic.

Explanation:
Aldosterone, from the adrenal cortex, acts on the distal tubule and collecting duct to increase sodium reabsorption (and water follows) and potassium secretion, raising blood volume and pressure. ADH increases water reabsorption, ANP reduces sodium reabsorption, renin is an enzyme initiating the RAAS.