Question 18M.3.SL.TZ1.18
| Date | May 2018 | Marks available | [Maximum mark: 5] | Reference code | 18M.3.SL.TZ1.18 |
| Level | SL | Paper | 3 | Time zone | TZ1 |
| Command term | Outline, State | Question number | 18 | Adapted from | N/A |
State one role of fibre in the diet.
[1]
aids peristalsis / reduces risk of intestinal disorders/cancer/constipation / reduces hunger
Outline control of digestive juice secretion so that digestive juices are only secreted into the gut when there is food present.
[2]
a. combination of nervous AND hormonal control
b. food in stomach stimulates chemoreceptors/stretch receptors / stretches the wall
c. causes production of gastrin
d. arrival of chyme to the small intestine triggers the release of hormones/secretin
e. volume and composition of gastric juices are controlled
Outline the role of intestinal villi.
[2]
a. villi/microvilli provide large surface area
b. capillary network for absorption and transport
c. lacteal for absorption and transport of lipids/fatty acids/glycerol / bile resorption
d. mitochondria in epithelial cells provide energy for absorption