In a dihybrid cross, the F₂ phenotypic ratio is: MCQ with Answer and Explanation

Explanation:
Root hairs, unicellular extensions of epidermal cells in the root maturation zone, greatly increase surface area for water and mineral absorption from the soil. Water enters by osmosis. Leaves absorb some water through stomata but primarily lose water. The stem transports, and flowers are reproductive.

Explanation:
Epistasis is a form of gene interaction where the expression of one gene (the epistatic gene) masks, suppresses, or modifies the expression of another non-allelic gene (the hypostatic gene). This alters the expected Mendelian dihybrid ratio (9:3:3:1) into modified ratios like 9:7 (complementary), 9:3:4 (recessive epistasis), or 12:3:1 (dominant epistasis). Pleiotropy is one gene affecting multiple traits, and linkage is genes being on the same chromosome.

Explanation:
Stomatal transpiration, which occurs through the stomata (pores) on the leaf epidermis, accounts for about 90% of the total water loss in plants. Cuticular transpiration occurs through the waxy cuticle and is minimal. Lenticular transpiration occurs through lenticels in woody stems and is also very small.