Digestion And Absorption Flashcards
What are two stages of digestion
Physical breakdown
Chemical digestion
What is physical breakdown
Break large pieces of food into smaller pieces to increase surface area for enzyme action
What is chemical digestion
Chemical breakdown of chemical food molecules into smaller soluble molecules by enzymes all of these enzymes are hydrolases where water is supplied
Digestion Starch to maltose in mouth
Salivary amylase
Hydrolysis of glucosidic bonds
Ph 7
What happens to salivary amylase in stomach
Salivary Amylase denatures
Ph 1-2
maltose, sucrose or lactose to constituent monosaccharides
In duodenum and ilium
Membrane bound maltase, lactase or sucrase hydrolyse them into constituent monosaccharides by breaking glycosidic bonds
What is ilium
Small intestine
How do glucose or amino acids get absorbed into blood stream
Sodium potassium pump means sodium goes into bloodstream by active transport
Low conc of sodium in epithelial cells and high in ilium
Co transport of glucose and sodium into cells
Glucose goes to bloodstream by facilitated diffusion
Protein to polypeptide
Stomach
Endopeptidases hydrolysis of internal peptide bonds
Polypeptides to dipeptides and amino acids
Duodenum
Exopeptidase hydrolyse external peptide bonds
Dipeptides to amino acids
Ilium
Membrane bound peptidase hydrolysis of peptide bonds
What is visking tubing
Semi permeable tube used to imitate epithelial cells around ilium
Two types of mutations
Point mutations
Chromosome mutation
Three types of point mutations
Substitution
Deletion
Insertion
What are the three effects of point mutation
Silence
Missense
Nonsense
