Digestion

Question 1

Carbohydrate digestion

Answer 1

1. Starch -> oligosaccharides by amylase
2. Oligosacchardies -> monosaccharides by oligosaccharidases (e.g. maltase, lactase)

Question 2

Protein digestion

Answer 2

1. Proteins -> AA or oligopeptides by pepsin/pancreatic protesases
2. Any oligopeptides are broken into AA at the brush border

Question 3

Lipids digestion

Answer 3

1. Formed into droplets by chewing/gastric enzymes
2. Lipid droplets get amphiphilic coat to become micelles
3. Micelles -> free fatty acids, monoglycerides, glycerol by pancreatic lipase in intestinal phase
4. Triglycerides -> monoglycerides and 2 fatty acids by gastric lipase in gastric phase

Question 4

Iron digestion

Answer 4

1. Fe3+ -> Fe2+ as ingested form cannot be absorbed so HCl, vitamin C, and ferric reductase encourage reduction

Question 5

Vitamin B12 digestion

Answer 5

Vitamin B12 binds to intrinsic factor to allow absorption

Question 6

General digestion

Answer 6

Digestion takes place in the stomach/small intestine. Gastric secretions often stimulate the release of digestive enzymes from the pancreas where they are generally stored