The primary xylem in roots is: MCQ with Answer and Explanation

Explanation:
Light reactions occur in the thylakoid membranes, where photosystems I and II, electron transport chains, and ATP synthase are located. Light energy is captured to produce ATP and NADPH and split water. The Calvin cycle (light-independent) occurs in the stroma.

Explanation:
Chlorophyll a is the primary photosynthetic pigment that acts as the reaction center in photosystem I (P700) and II (P680), converting light energy to chemical energy. Accessory pigments like chlorophyll b, carotenes, and xanthophylls absorb light and transfer energy to chlorophyll a. Phytochrome is involved in photoperiodism. Without chlorophyll a, photosynthesis cannot occur.

Explanation:
When both parents are heterozygous (Tt × Tt), the offspring genotypes are TT (25%), Tt (50%), and tt (25%). Since tall (T) is dominant over dwarf (t), both TT and Tt are tall, resulting in 3 tall : 1 dwarf phenotypic ratio. The genotypic ratio is 1:2:1. 9:3:3:1 is the dihybrid phenotypic ratio. 1:1 ratio is seen in test cross (Tt × tt).