Consider statements about human diseases: 1. Cholera is a bacterial disease. 2. Polio is a viral disease. 3. Malaria is transmitted by a mosquito. Which are correct? MCQ with Answer and Explanation

Explanation:
Digestion converts complex, insoluble food molecules into simple, soluble forms that can be absorbed. It involves mechanical action (chewing, churning) and enzymatic hydrolysis. Absorption is the uptake of nutrients, assimilation is incorporation into body tissues, egestion is elimination of undigested waste.

Explanation:
The inner surface of the small intestine is lined with finger-like projections called villi, which increase the surface area for absorption. The epithelial cells (enterocytes) covering these villi have their own microscopic, finger-like projections on their apical surface, called microvilli. Collectively, these microvilli form a 'brush border'. This further massively increases the surface area, maximizing the efficiency of nutrient absorption. Cilia are motile, and stereocilia are found in the inner ear and epididymis.

Explanation:
In aerobic respiration, oxygen accepts electrons at the end of the ETC, forming water. Without it, the chain would halt. This directly explains why oxygen is required.