Digestion Flashcards
(32 cards)
What enzyme starts starch digestion in the mouth and pancreas?
Amylase (salivary/pancreatic).
What does amylase break starch into?
Maltose.
What enzyme breaks maltose into glucose?
Maltase.
Where is maltase found?
Membrane-bound disaccharides.
What type of reaction breaks down starch?
Hydrolysis.
What bonds are hydrolysed in starch digestion?
Glycosidic bonds.
What transports sodium ions from ileum cells into blood?
Active transport.
What gradient is maintained for sodium to re-enter ileum cells?
Diffusion gradient.
How does glucose enter ileum cells?
By facilitated diffusion with sodium ions (co-transport).
What increases surface area for absorption in ileum cells?
Folded membrane / microvilli.
What do microvilli provide?
Large surface area for absorption.
What do carrier/channel proteins help with in absorption cells?
Fast rate of absorption.
Why are mitochondria abundant in absorption cells?
To release ATP for active transport.
What do membrane-bound digestive enzymes help maintain?
Concentration gradient for fast absorption.
What do micelles contain?
Bile salts and fatty acids/monoglycerides.
What do micelles make fatty acids/monoglycerides?
More soluble in water.
What do micelles do for fatty acids?
Bring them to the ileum lining.
What gradient do micelles maintain for fatty acids?
High concentration near the ileum lining.
How are fatty acids absorbed?
By diffusion.
What happens to fatty acids/monoglycerides in ileum cells?
Reformed into triglycerides.
What happens to triglycerides in ileum cells?
Packaged into vesicles that move to the membrane.
What do endopeptidases hydrolyse?
Internal peptide bonds.
What do endopeptidases produce?
Shorter polypeptides / more ends.
What do exopeptidases hydrolyse?
Peptide bonds at the ends of polypeptides.
