Done digestion, heart Flashcards
(48 cards)
Biles two function:
○ Emulsifies lipids to smaller droplets
Increases surface area for lipase activity
increases rate of hydrolysis
Forms micelles
Bile shell around monoglycerides and fatty acids to keep dissolved in ileum contents
Transports digestion products to cell membrane for absorption
Absorption of AA/ glucose
1 - NA AT out of epithelium cells into blood by sodium potassium pump - uses ATP
2- NA conc gradient created, high inside ilium, low in epithelium cell
3- AA/ Glucose are cotransported into epithelium cells with NA
- AA/ G move against conc gradient
- NA moves down conc gradient
4- G/ AA move via facilitated diffusion from epithelium cells to blood
Illum adapations
micelle - move FA and G to epitheiulim cells - plum
- very long
VILLI - finger like projections
- thin walls - 1 cell thick - short diffusion distance
- good blood supply - lots of capillaries - maintain diffusions gradient
- increases SA for diffusion
- MICRO VILLi
Absorption of lipids
BIle- micelle
FA and G simply diffuse across the membrane into cell
Then go to smooth endoplasmic reticulum- recombined form triglycerides
TO Golgi - Trigylcerieds associate with chloroesrtol and lipoprotein to form chylomicrons
- transported by vesicles to CSM and released by extocytosis
- enters lacteal - transport lipids via lymphatic vessels into blood vessels
Endopeptidases
Hydrolyses peptide bond sin middle region of polypeptide chain
Exopeptidases
Hydrolyses peptide bonds on terminal amino acid
Membrane bound dipeptidases
Hydrolyses dipeptidases into 2 Amino acids
Digestive enzymes
active site, specific teriratry structure, can only bind to, form enzymes substrate complexes
lipids bonds
ester bonds
starch bonds
glycosidic bonds
Suggest and explain why the combined action of endopeptidases and exopeptides are more efficient than exopeptidase on their own
(Def of each)
then..
More ends
increase in surface area
The addition of a respiratory inhibitor stops the absorption of amino acids. Use the diagram about cotransport to explain why?
less ATP
NO active transport
Sodium not moved into cell
NO diffusion gradient for sodium
NO concentration gradient for sodium
Which process is by which fatty acids and glycerol enter the intestinal epithelium cell
Diffusion
Explain the advantages of lipids droplet and micelle formation
Droplots increases surface area
so faster hydrolysis
Micelle carry fatty acids and glycerol through membrane to cell
How is the Golgi involved in the absorption of lipids
Modifies/ processes triglycerides
Combines triglycerides with protein
Packaged for release/ exocytosis
Forms vesicles
Test for lipids
Dissolve in alcohol, then add water
White emulsion shows presence of lipids
Explain why this lipid is unsaturated
contains double bond between adjacent carbon atoms in hydrocarbon chain
How to calculate percentage by mass of lipid
DIvide mass of each lipid by total mass of all lipids
then x100
AWAY=
arteries
Atrium
thin walled
elastic
stretches as collects blood
Venticles
higher pressure
thicker walled
has to contract strongly to pump blood further distances - body or lungs
Hydrostatic pressure
of tissue fluid outside the capillaries, which resists towards movement of liquid.
The lower the water potential
of the blood, due to the plasma proteins, that causes water to move back into the blood within the capillaries
Formation of tissue fluid
In capillaries the hydrostatic pressure is higher at the arterial end
This pushes fluid out of the cappilaires
It is opposed by the WP of the blood
- lower that that of tissue fluid and lower than hydrostatic pressure of the tissue fluid
Overall fluid is forced out from the capillaries by ultrafiltration
- only pushes small molecules (not cells and protein)
