The hormone that stimulates the reabsorption of sodium and water in the kidney is: MCQ with Answer and Explanation

Explanation:
Glucagon, secreted by alpha cells of the pancreas when blood glucose is low, binds to liver receptors activating glycogenolysis (glycogen → glucose) and gluconeogenesis. Insulin promotes glycogenesis (glucose → glycogen). Thyroxine affects metabolism, somatostatin inhibits both insulin and glucagon.

Explanation:
Stomata are microscopic pores typically on the lower epidermis of leaves, bounded by two guard cells that regulate opening and closing for gas exchange (CO₂ in, O₂ out) and transpiration. Lenticels are on bark, hydathodes release water droplets (guttation), sclereids are thick-walled sclerenchyma cells. Stomatal density varies with environmental conditions.

Explanation:
ELISA (enzyme-linked immunosorbent assay) uses enzyme-linked antibodies to detect and quantify specific antigens or antibodies in a sample. PCR amplifies DNA, Northern blotting detects RNA, Southern blotting DNA.