Consider statements about ecology: 1. A food chain shows energy flow. 2. A food web shows interconnected food chains. 3. The pyramid of energy is always inverted. Which are correct? MCQ with Answer and Explanation

Explanation:
The Golgi apparatus consists of cisternae that modify, sort, and package proteins and lipids received from the ER for secretion or delivery to other organelles. The smooth endoplasmic reticulum (SER) lacks ribosomes and is the primary site for the synthesis of lipids, including phospholipids and steroids. The rough endoplasmic reticulum (RER) has ribosomes attached and is primarily involved in protein synthesis, not lipid synthesis. Thus, statements 1 and 2 are correct.

Explanation:
Fertilization in humans typically occurs in the fallopian tube (ampullary region), not the uterus; the zygote then travels to the uterus for implantation. The placenta is the vital organ providing oxygen and nutrients to the growing fetus and removing waste. Spermatogenesis, the production of sperm, occurs in the seminiferous tubules of the testes. Thus, statements 2 and 3 are correct.

Explanation:
The tricuspid valve (right atrioventricular valve) has three cusps and closes during ventricular systole to prevent regurgitation into the right atrium. The bicuspid (mitral) is on the left side. Aortic and pulmonary valves are semilunar valves at the ventricular outlets.