The AB blood group in the ABO system is an example of: MCQ with Answer and Explanation

Explanation:
Peroxisomes contain catalase and other oxidases that detoxify hydrogen peroxide and other harmful substances. They also play a role in lipid metabolism. Lysosomes contain hydrolytic enzymes, Golgi modifies proteins, nucleus houses DNA. Peroxisomes are abundant in liver and kidney cells.

Explanation:
Phototropism (positive in shoots) is caused by the migration of auxin to the shaded side of the shoot, promoting cell elongation more on that side, causing the shoot to bend towards light. This asymmetric auxin distribution was demonstrated by Went's experiments. Auxin is sensitive to light and moves laterally. This is a growth response to directional light.

Explanation:
Epithelial tissue forms sheets covering external surfaces (skin) and lining internal organs and cavities. It functions in protection, absorption, secretion, and sensation. Connective tissue supports and binds, muscle contracts, nervous transmits impulses. Epithelial cells are tightly packed with little extracellular matrix.