3.1.2 (digestion) - part 2 Flashcards
Protein - digestion
- Stomach
Chemical digestion of proteins start in the stomach.
- Stomach releases gastric acid containing hydrochloric acid (HA).
- Pepsin is released amongst the gastric juices.
- HA activates P which begins the breakdown of protein into amino acid (enzymatic hydrolysis).
Protein - digestion
- small intestine
Pancreatic protease released from pancreas into SI where it breaks down the proteins further into amino acids + peptides.
Protein - absorption
Occurs in the small intestine.
- Amino acids are moved from the villi to the bloodstream which then transports the amino acids to the cells in the body as needed.
Protein - utilisation
- Body uses protein for growth, maintenance, + repair of body cells (eg. muscles, blood, connective tissues, etc).
- Protein assist in energy production.
- Secondary energy source for growth + activity.
Fats - digestion
- Mouth
Lingual lipase is released by saliva but doesn’t begin to work until it reaches the stomach.
Fats - digestion
- Stomach
Acid in the stomach activates lingual lipase, joined by gastric lipase released in the stomach, beginning fat digestions.
Fats - digestion
- Liver
Liver releases bile that mixes with the chyme in the SI.
- Bile = digestive fluid produced by liver, stored in gall bladder, released into SI. Facilitates growth by acting as an emulsifier.
- Bile breaks down fat into smaller particles providing a larger surface area for digesting lipases.
Fats - absorption
Fatty acids + glycerol are absorbed into villi of the SI + mix with lymphatic fluid.
- They move around the body in the lymphatic system, joining blood circulation as insoluble fats.
Fats - utilisation
- Used for insulation + protection around vital organs.
- Helps transport fat-soluble vitamins.
- Used as a secondary energy source.
- Any fat not used by the body is stored as adipose tissue.