IB myp 4-5 Biology – Practice Questions- All Topics
Topic :Metabolism-Biochemistry and Enzymes
Topic :Metabolism– Weightage : 21 %
All Questions for Topic : Nutrition,Digestion,Biochemistry and enzymes,Movement and transport,Diffusion,Osmosis,Gas exchange,Circulation,Transpiration and Translocation,Homeostasis
Question:
Predict what will happen to lactose in the intestines of adults who do not produce the enzyme lactase.
▶️Answer/Explanation
Ans: Lactose is not digested (by human enzymes/digestive juices); bacteria/microbes in the gut digest the lactose.
Question:
Explain how lactase secretion in adulthood could have become common in populations that keep cattle or other mammals and drink their milk.
▶️Answer/Explanation
Ans: Adults that continue to secrete lactase into adulthood have an advantage; they are better nourished on a diet containing milk; they avoid harmful effects of lactose intolerance; they are healthier so produce more children; their children inherit the trait of secreting lactase in adulthood.
Question:
Deduce which hormone causes these processes:
a) conversion of glycogen to glucose
▶️Answer/Explanation
Ans: Glucagon.
b) use of glucose rather than fat by body cells to generate energy by respiration.
▶️Answer/Explanation
Ans: Insulin.