Identify the INCORRECT statement about the respiratory system: MCQ with Answer and Explanation

Explanation:
Photosynthesis consists of light-dependent reactions occurring in the thylakoid membranes (grana) where water is split, releasing oxygen, and light-independent reactions (Calvin cycle) occurring in the stroma where CO2 is fixed. The oxygen released during photosynthesis comes from the photolysis of water, not from carbon dioxide. Thus, statements 1 and 2 are correct.

Explanation:
Mitochondria are membrane-bound organelles present in almost all eukaryotic cells but absent in prokaryotes, which carry out respiration on the plasma membrane or mesosomes. Ribosomes, cell wall (in most), and plasma membrane are present in both.

Explanation:
Egestion (defecation) is the removal of undigested solid waste from the digestive tract. Absorption is uptake of nutrients, assimilation is incorporation into cells, digestion is breakdown of food.