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wis ate 4, , Or Gti, , Directions : In the following questions, A, statement of Assertion (A) is followed by a, , Statement of Reason (R). Mark the correct choice, as:, , (A) Both A and R are true and R is the correct, , explanation of A., , (B) Both A and R are true but R is NOT the correct, , explanation of A., , (C) Ais true but R is false., (D) A is false and R is true., , Q.1., , Ans., , Assertion (A): HCI converts pepsinogen into active, enzyme pepsin., , Reason (R): Pepsin converts protein into proteoses, and peptones., , Option (B) is correct., , Explanation: HCl creates an acidic medium,, which facilitates activation of Pepsinogen into, pepsin. The active enzyme pepsin converts, proteins into proteoses and peptones., , - Assertion (A): Digestion breaks large complex, , molecules to simple smaller molecules which can, be easily absorbed., , Reason (R): Digestion is necessary for the, absorption of all molecules., , Ans. Option (C) is correct., , Explanation: Digestion breaks large complex, organic molecules to simple smaller ones, which can be easily absorbed. However, certain, molecules such as glucose, vitamin C etc, do, not need any digestion before their absorption., , - Assertion (A): Muscles of stomach wall Possess, , thick layers of muscle fibers., , Reason (R): These muscles help in mixing the food, with the enzymes present in the alimentary canal., , Ans. Option (A) is correct., , Q.4., , Ans., , Explanation: The lining of alimentary canal, has muscles that contract rhythmically in order, to push the food forward. This is known as, peristaltic movement., , Assertion (A): Lipases help in emulsification of, fats., , Reason (R): Lipases hydrolyses fats and oils., Option (D) is correct., , Explanation: Bile helps in emulsification of, fats whereas lipases are the enzymes which, hydrolyze fats and oils., , Q.5., , , , Assertion (A): Photosynthesis is an anabolic, S s, , Bale (R): The process of photosynthesis occurs, e, , in chlorophyll., , Ans. Option (C) is correct., , : i i, ation: Photosynthesis is an ana, eee as it takes CO, and H,O and then, C oeabls them into glucose. The process of, photosynthesis occurs in chloroplast., , . Assertion (A): Energy is used during the process of, , respiration., Reason (R): Respiration stores energy in the form, of ATP., , Ans. Option (D) is correct., , Q.7., , Explanation: Respiration involves the, oxidation of glucose inside the mitochondria, to produce energy, which is stored in the high, energy bonds of ATP molecules as biologically, useful energy., , Assertion (A): Humans are not truly aerobic., Reason (R): They produce lactic acid anaerobically., , Ans. Option (B) is correct., , Ans. Option (B) is correct., , - Assertion (A): Aly, , Explanation: Humans are aerobically respiring, animals, but sometimes anaerobic respiration, takes place in certain tissues like skeletal, muscles, which do not get immediately as, , much oxygen as it requires. Therefore, the, muscles respire anaerobically and produce, lactic acid from glucose., , respiratory system,, , Reason (R): Human skin is impermeable to gases., , pe. need more oxygen to, Maintain their high :, , eoli contain an extensi twork, of blood ce ensive ne, , Reason (R): Alveoli, , ae sy the site where exchange 0, , Ans. Option (A) is correct,