The 'Hormone Leptin' is primarily secreted by adipose (fat) tissue and acts on the hypothalamus to: MCQ with Answer and Explanation

Explanation:
The nephron is the structural and functional unit of the kidney, responsible for filtration, reabsorption, and secretion to form urine. Each kidney has about 1 million nephrons. A nephron consists of the Bowman's capsule, glomerulus, proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting duct. Neurons are units of nervous system, alveoli of lungs, hepatocytes of liver.

Explanation:
Mendel selected Pisum sativum because it had distinct contrasting traits, was easy to cultivate, and was naturally self-pollinating, allowing controlled crosses. R explains A correctly.

Explanation:
The endomembrane system includes ER, Golgi apparatus, lysosomes, vacuoles, and the nuclear envelope—organelles that coordinate membrane flow and protein processing. Mitochondria (and chloroplasts) are not part of this system because they are semi-autonomous, arising from endosymbiosis, and are not connected by vesicle trafficking. Peroxisomes are sometimes considered associated but not part of the ER-derived system.