Nutrient Digestion- Fats, Vitamins and minerals Flashcards
Where is fat digested?
In the small intestine
Name the enzyme that digests fat
Pancreatic lipase
What is triacyglycerol?
Large lipid droplet that is insoluble in water
What is lipase?
Water soluble enzyme
What is emulsification?
Dividing large lipid droplets into smaller droplets
What does the emulsifying agent do?
Prevents small droplets from reforming large ones
Name 2 emulsifying agents
Phospholipids and bile salts
What grinds and mixes luminal contents?
Smooth muscle contraction
What enhances the absorption of lipids?
The formation of micelles
What are Micelles made up of?
Bile salts, phospholipids, fatty acids and monoglyceride
What parts of the micelle are absorbed?
Just the fatty acids and monoglycerides
Why can’t chylomicrons pass through the capillary basement membrane?
They are too large
Where do chylomicrons go once they move through the lacteals and into the endothelial cells?
They then go into lymphocytes
Name 4 fat soluble vitamins
Vitamin A, D, E, K
How are fat soluble vitamins absorbed?
Follow the same absorption path as fat
Name 3 water soluble vitamins
B group, Vitamin C and folic acid
How are water soluble vitamins absorbed?
Passive diffusion and carrier mediated transport
What is vitamin B12?
Large charged molecule
What does vitamin B12 bind to and where does this happen?
It binds to the intrinsic factor in the stomach
Where does the vitamin B12 complex move to?
Moves to the distal ileum
What is the vitamin B12 complex important for?
It forms the biconcave disc shape of red blood cells
What does a deficiency of vitamin B12 cause?
Pernicious anaemia
What is iron transported across?
The intestine and into the blood
What are iron ions incorporated into?
Ferritin
What does iron in the blood bind to?
Transferrin
Where is unbound iron transported?
It is transported into the duodenal enterocytes
What is hyperanaemia due to?
Increased ferritin levels- this therefore increases the blood bound in enterocytes
What is anaemia due to?
Decreased ferritin levels
What are extracellular fat droplets called?
Chylomicrons
