Fig. 2.1 is a diagram of part of the human digestive system. Fig. 2.1 Many processes occur in the digestive system. The boxes on the left show some of the processes. The boxes on the right show descriptions of some processes. Draw one line to link each process to its description. Draw four lines. BLANK PAGE

Biology

IGCSE&ALevel

CAIE

Exam No：0610_w23_qp_31 Year：2023 Question No：2(c)

Answer:

Knowledge points:

7.3.1 Identify the types of human teeth (incisors, canines, premolars and molars)

7.3.2 Describe the structure of human teeth, limited to enamel, dentine, pulp, nerves and cement, as well as the gums

7.3.3 Describe the functions of the types of human teeth in mechanical digestion of food

7.3.4 State the causes of dental decay in terms of a coating of bacteria and food on teeth, the bacteria respiring sugars in the food, producing acid which dissolves the enamel and dentine

7.3.5 Describe the proper care of teeth in terms of diet and regular brushing

7.4.1 State the significance of chemical digestion in the alimentary canal in producing small, soluble molecules that can be absorbed

7.4.10 Outline the role of bile in neutralising the acidic mixture of food and gastric juices entering the duodenum from the stomach, to provide a suitable pH for enzyme action

7.4.11 Outline the role of bile in emulsifying fats to increase the surface area for the chemical digestion of fat to fatty acids and glycerol by lipase

7.4.2 State the functions of enzymes as follows: – amylase breaks down starch to simpler sugars – protease breaks down protein to amino acids – lipase breaks down fats to fatty acids and glycerol

7.4.3 State where, in the alimentary canal, amylase, protease and lipase are secreted

7.4.4 State the functions of the hydrochloric acid in gastric juice, limited to killing bacteria in food and giving an acid pH for enzymes

7.4.5 State the functions of the hydrochloric acid in gastric juice, limited to killing bacteria in food and giving an acid pH for enzymes

7.4.6 State the functions of the hydrochloric acid in gastric juice, limited to killing bacteria in food and giving an acid pH for enzymes

7.4.7 Describe the digestion of starch in the alimentary canal: – amylase is secreted into the alimentary canal and breaks down starch to maltose – maltose is broken down by maltase to glucose on the membranes of the epithelium lining the small intestine

7.4.8 Describe pepsin and trypsin as two protease enzymes that function in different parts of the alimentary canal: – pepsin in the stomach – trypsin in the small intestine

7.4.9 Explain the functions of the hydrochloric acid in gastric juice, limited to the low pH: – denaturing enzymes in harmful microorganisms in food – giving the optimum pH for pepsin activity

Answer:

Knowledge points:

Solution:

Related Question