The structure that regulates the size of the pupil is the: MCQ with Answer and Explanation

Explanation:
Gel electrophoresis is a widely used technique to separate charged molecules, primarily DNA, RNA, or proteins, in an electric field through a gel matrix (usually agarose for DNA). DNA fragments are separated based on their size (length in base pairs). Smaller fragments move faster and further through the gel than larger ones. The separated DNA bands are visualized using ethidium bromide and UV light.

Explanation:
Apical dominance is the phenomenon where the main central stem (apical bud) grows more strongly than the side stems (lateral buds). This is primarily controlled by auxin (specifically IAA), which is produced at the shoot apex and moves downwards, inhibiting the growth of lateral buds. Removal of the apical bud promotes lateral branching.

Explanation:
Capitulum (head) is characteristic of the Asteraceae family, where numerous small florets are arranged on a flattened disc. Raceme has flowers on pedicels along an elongated axis, spike sessile, umbel umbrella-like. Sunflower inflorescence is a capitulum.