Q1. The digestive system processes food, extracts nutrients and removes the residue.
Q2. Why are some digestive enzymes secreted as the zymogens?
A. As this saves one step in their synthesis.
B. As gastric cells don’t have the essential enzymes for their synthesis.
C. So they begins digesting intracellular proteins of gastric cells more rapidly
D. So they act just in the stomach lumen and don’t digest the intracellular proteins
E. So they can begin digesting dietary proteins more rapidly
Q3. The small intestine has a very big absorptive surface related with all these structures apart from:
A. Circular folds (plicae circulares).
B. Intestinal length.
Q4. The buccal stage of swallowing is under _____________ control and the pharyngo-esophageal stage is ______________.
A. Central nervous system; also controlled by the central nervous system
B. Central nervous system; controlled by autonomic reflexes
C. Autonomic nervous system; controlled through autonomic reflexes
D. Voluntary; as well voluntary
E. Involuntary; as well involuntary
Q5. Chemical digestion breaks down ____________ into the _____________.
A. Proteins; nucleotides
B. Amino acids; proteins
C. Polysaccharides; amino acids
D. Nucleic acids; nucleotides
E. Fatty acids; cholesterol