Which one of the following statements regarding the secretions of the stomach is correct?

It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.

With regards to the pancreatic juice produced in response to a meal, which ONE of the following statements is CORRECT?

Bicarbonate is produced by the pancreatic duct cells and neutralises the acidic stomach contents as they enter the small intestine.

The function of the gastrointestinal tract can be classified in several ways. Which of the following functions is most important for survival immediately after a meal?

a) Absorption and retention of water and electrolytes

b) Elimination of toxins

c) Maintenance of barrier function

d) Extraction of maximum value from nutrients

Question 3

Water transport can occur from the lumen of the intestine to the blood stream, or from the blood stream to the intestinal lumen. Which single statement about this phenomenon, below, is actually correct?

a) A "flip-flop" mechanism efficiently transports water directly across the enterocyte membrane

b) Water flows into the gut from the mucosa, during digestion of starch and protein, in order to reduce luminal osmolality

c) Water is mostly absorbed by movement between the cells lining the gut (enterocytes) via tight junctions

d) Dietary intake of water is always greater than water movement in the small intestine

Question 4

Which statement about intestinal "brakes" and "accelerators" is FALSE?

a) Dietary starch is a potent stimulator of small intestinal motility because it causes insulin release from the pancreas

b) Food in the stomach causes gastrin release, which stimulates acid secretion

c) Short-chain fatty acids which move from colon to caecum (reflux) promote ileo-caecal motility

d) The arrival of lipid in the duodenum causes an immediate reduction in motility and a switch from the "fasting" to the "feeding" pattern.

Question 5

Which single statement about fat digestion and absorption is correct?

a) Absorption of fatty acids in the intestine occurs mainly through FABP and FAT/CD36 transport proteins in the enterocytes of the distal duodenum

b) After absorption, medium chain triglycerides (MCT) enter the lymphatic system, whereas long chain triglycerides enter the portal blood system.

c) The products of partial digestion of triglycerides (triacylglycerols) can form mixed micelles with pancreatic cholesterol and phospholipids and this increases absorption

d) Triglycerides (triacylglycerols) must be emulsified and digested before the fatty acids can be transported

Question 6

Which statement about protein digestion and absorption is most correct?

a) The products of protein digestion may be absorbed as free amino acids or as di- or tripeptides

b) Gastric digestion of all proteins is equally efficient because of the grinding action of the antrum

c) Gastric zymogenic (chief) cells produce and secrete chymotrypsin, elastase and carboxypeptidase A and this initiates the process of protein digestion

d) The products of digestion of dietary protein by luminal and brush-border enzymes are only absorbed by one of the 14 different amino acid transporters

Question 7

Which statement about dietary fibre is most correct?

a) The end products of it fermentation is mainly malic, succinic and propionic acids

b) Fermentation studies in vitro, with human faeces, have shown that soluble and insoluble forms are fermented completely within 24 hours

c) Fibre sources, such as hemicelluloses, pectins and inulin are rapidly fermented to short chain fatty acids, which have trophic effects on the colon

d) Stool bulking occurs mainly through the action of insoluble fibres such as cellulose

Question 8

Which statement about absorption from the gastro-intestinal (GI) tract is most correct?

a) The absorption of glucose is associated with sodium uptake.

b) Fructose is absorbed more rapidly than glucose.

c) Galactose and fructose are absorbed by the same transporter at the brush border membrane.

d) Most water absorption along the GI tract occurs in the colon.

Question 9

Select the single most accurate statement about the absorptive area of the human intestine?

a) The absorptive area is equivalent to that of a tennis court

b) All of the options given are correct

c) Changes in motility increase the contact time between nutrients and absorptive surface

d) The presence of folds, villi and microvilli on the surface of enterocytes magnifies the absorptive area

Question 10

Which statement about the oral phase of digestion is INCORRECT?

a) About 2% of the energy content of food is expended during the action of chewing and swallowing it.

b) Swallowing involves contraction and relaxation of at least 14 groups of muscles in about 10 seconds in healthy subjects

c) The biofilm covering tooth enamel contains several salivary and bacterial enzymes

d) Salivary amylase digests the dextran film on tooth enamel formed from dietary sucrose

Question 11

The stomach lining contains several types of cells. Which statement about them is correct?

a) Mucous cells secrete the glycoprotein mucin

b) Chief cells the hormone gastrin (which stimulates acid secretion).

c) Parietal cells secrete pepsinogen, the inactive precursor of pepsin

d) G Cells secrete hydrochloric acid

Question 12

The pancreas secretes a large amount of digestive enzymes after a meal. Which statement about this process is correct?

a) Pepsinogen is the chief enzyme which digests protein and requires removal of a peptide sequence from the active cleft before it can work

b) Pancreatic á-amylase will hydrolyse starch to free glucose

c) Enteropeptidase converts trypsinogen to trypsin by cleavage of a peptide sequence that blocks the active site of trypsin.

d) Pancreatic secretion of hydrochloric acid is required to provide the correct pH for maximal pancreatic enzyme in the duodenum

Question 13

Intestinal motility is a complex process, orchestrated by nerves, hormones and the presence of food in the stomach. Which statement about this process is correct?

a) The migrating motor complex is chiefly responsible for peristaltic movement of food after a meal has been consumed

b) The release of insulin after eating a meal will slow the emptying of the stomach

c) At the start of a meal, the stomach increases its "tone" in order to develop pressure which will lead to expulsion of its contents, via the pylorus

d) The presence of partially digested fat and starch in the duodenum, slows intestinal motility

Question 14

The colonic microflora can be considered as "an organ within an organ". Which of the following statements best describes the functions of the microbiota?

a) Measurement of daily dietary fibre intake underestimates the amount of fermentable material entering the colon each day

b) All of the options given are correct

c) Acetate, propionate and butyrate are the chief organic acids produced by anaerobic colic fermentation

d) The establishment of an "acetate buffer" in the colonic lumen suppresses the growth of some pathogenic bacteria.

Question 15

Which of the following is the most plausible explanation for the protective effect of dietary fibre against cancer of the colon?

a) Propionic acid, formed during colonic fibre fermentation inhibits liver fatty acid synthesis

b) Butyric acid, formed during colonic fibre fermentation stimulates "silencing" of the SLC5A8 tumour suppressor gene

c) None of these options are correct

d) Butyric acid, formed during colonic fibre fermentation stimulates anti-oxidant defences in the colon

Question 16

Which statement best describes the process of absorption of vitamins from the intestine?

a) All of the options given are correct

b) Vitamin E is absorbed by a protein which normally binds peroxidised fatty acids to scavenge them

c) It is necessary to dephosphorylate thiamine pyrophosphate or pyridoxal phosphate before they can be absorbed

d) Oxidised vitamin C (dehydroascorbic acid) is absorbed by a glucose transporter

Question 17

Which of the following statements about the role of the intestine in development of obesity best describes the situation?

a) Obesity occurs because gut hormone secretion becomes deranged and PYY secretion fails to give a satiety signal.

b) The gut/brain signalling pathway controls energy intake to within 2% of requirements, even in people who are morbidly obese

c) The problem is one of greed and gluttony, whereby people override strong satiety signals on a regular basis

d) Flavour signals from tasty, processed food will override satiety signals even after a large meal

• reset
• + A
• - A

About the book

Find out more, read a sample chapter, or order an inspection copy if you are a lecturer, from the Higher Education website

Which of the following statements is true regarding one of the secretions that contribute to digestion?

Which of the following substances is secreted by the human stomach?

Which of the following is secreted from the stomach wall?

Which type of substances are secreted by glands in the stomach lining?