Consider statements about genetics: 1. A codon consists of three nucleotides. 2. The start codon is AUG. 3. Introns are coding sequences. Which are correct? MCQ with Answer and Explanation

Explanation:
Villi are microscopic finger-like projections on the inner lining of the small intestine, covered with microvilli (brush border), greatly increasing surface area for absorption of digested nutrients. Each villus contains a lacteal (lymph capillary) and blood capillaries. Alveoli are in lungs, nephrons in kidneys, cilia are hair-like projections on cells.

Explanation:
The common cold is a viral infection of the upper respiratory tract, primarily caused by rhinoviruses. Typhoid fever, caused by Salmonella typhi, is transmitted via the fecal-oral route through contaminated food and water. Plague, caused by Yersinia pestis, is a zoonotic disease transmitted to humans primarily by the bite of infected rat fleas (Xenopsylla cheopis). All three statements are correct.

Explanation:
Totipotency is the genetic ability of a single plant cell to divide and differentiate into all the cell types of the plant, ultimately generating an entire new plant. This property is the fundamental basis of plant tissue culture. Micropropagation is the technique used to rapidly multiply plants using this totipotency, often through the formation of callus and somatic embryos.