The blood group known as the universal donor is: 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:
ATP synthase (Complex V) uses the proton gradient generated by the electron transport chain to phosphorylate ADP to ATP. Cytochrome oxidase is Complex IV, succinate dehydrogenase is part of the Krebs cycle and Complex II, citrate synthase is in the Krebs cycle.

Explanation:
The phylum Echinodermata (spiny-skinned animals like starfish, sea urchins, sea cucumbers) is uniquely characterized by a water vascular system used for locomotion, capture and transport of food, and respiration. The tube feet are the terminal effectors of this system. They exhibit secondary radial symmetry in adults, though their larvae are bilaterally symmetrical. Mollusks have a muscular foot, and arthropods have jointed appendages.