The 'Emerson enhancement effect' demonstrated that photosynthesis is more efficient when: MCQ with Answer and Explanation

Explanation:
The cohesion-tension theory states that transpiration from leaves creates tension, pulling water up the xylem; water molecules cohere, forming a continuous column. Root pressure is minor.

Explanation:
The stomach secretes gastric juice containing hydrochloric acid and the enzyme pepsin, which initiates the digestion of proteins into smaller peptides. The small intestine is the primary site for the final digestion of food and the absorption of most nutrients (amino acids, simple sugars, fatty acids, vitamins) into the bloodstream through its villi. The large intestine (colon) primarily absorbs water, electrolytes, and some vitamins produced by gut bacteria, forming solid feces. All statements are correct.

Explanation:
A peptide bond is a covalent bond formed between the carboxyl group (-COOH) of one amino acid and the amino group (-NH₂) of another, releasing a water molecule (condensation reaction). Glycosidic bonds link monosaccharides, phosphodiester bonds link nucleotides in DNA/RNA, hydrogen bonds stabilize secondary structures. Peptide bonds create the polypeptide backbone.