The gland that secretes melatonin, regulating the sleep-wake cycle, is the: MCQ with Answer and Explanation

Explanation:
Cyanobacteria contain chlorophyll a (like plants) along with phycobilins (phycocyanin and phycoerythrin). Chlorophyll b is in green plants, phycocyanin is an accessory pigment.

Explanation:
The Glomerular Filtration Rate (GFR) is the volume of fluid filtered from the renal glomerular capillaries into the Bowman's capsule per unit time. In a healthy adult, the normal GFR is approximately 125 ml per minute, which amounts to about 180 liters per day. Almost all of this filtrate is reabsorbed, leaving only 1.5 liters of urine.

Explanation:
The corpus luteum, formed after ovulation, secretes progesterone (and some estrogen) to maintain the uterine lining for pregnancy. If no fertilization, it degenerates, causing menstruation. Estrogen is also produced by growing follicles, testosterone by Leydig cells, prolactin by anterior pituitary.