digestion and absorbtion

Question 1

how molecules broken down ?

Answer 1

hydrolysis

Question 2

what two enzymes are involved in carbohydrate digestion ?

Answer 2

Amylases
membrane bound diassaccarides

Question 3

where is amylase produce ?

Answer 3

pancreas
salivary gland

Question 4

what does amylase do ?

Answer 4

hydrolyse polysaccarides into diassaccarides maltose by hydrolysing glysocidic bonds

Question 5

what does amylase do ?

Answer 5

sucrase and lactase are membrane bound organnelles that hydrolyse sucrose and lactose into monosaccharides

Question 6

where does digestion of carboydrates occur?

Answer 6

mouth -> duodenum ->ileum

Question 7

what are three enzymes in protein digestiion ?

Answer 7

endopeptidase
exopeptidase
membrane bound dipeptidase

Question 8

what does endopeptidase do?

Answer 8

hydrolyse peptide bond between amino acid in middle of polymer chain

Question 9

what do exopeptidases do ?

Answer 9

hydrolyse peptide bond between amino acid on ends of a polymer chain

Question 10

what membrane bound dipeptiidases do ?

Answer 10

hydrolyse peptide bonds between two amino acids

Question 11

where does protein digestion occur ?

Answer 11

stomach ->duodenum -> fully digested in ileum

Question 12

what enzymes are involved in lipids ?

Answer 12

lipase and bile salts

Question 13

where is lipase produces ?

Answer 13

pancrease

Question 14

what can lipase do ?

Answer 14

hydrolyse ester bonds in triglycerides to form monoglycerides and fatty acids

Question 15

where do lipase secrete its enzymes

Answer 15

duodenum and ileum

Question 16

where are bile salts produce?

Answer 16

liver

Question 17

what can bile salts do ?

Answer 17

emulsify lipids and form tiny droplets called micelles

Question 18

what is the purpose of bile salts producing micelles ?

Answer 18

increases surface area for lipase to act on

Question 19

what are the two stages of lipid digestion ?

Answer 19

physical and chemical

Question 20

what is physical digestion of lipids?

Answer 20

emulsification and micelle formation

Question 21

what is chemical digestion of lipids ?

Answer 21

lipase

Question 22

what happens in physical digestion of lipids ?

Answer 22

lipids get coated in bile salts to create an emulsion .many small droplets of lipids provides a larger surface area to provide faster hydrolysis by lipase

Question 23

what happens in chemical digestion if lipids?

Answer 23

lipase hydrolyses triglycerides into triglycerides , glycerol and fatty acids

Question 24

what is a micelle ?

Answer 24

water solouble vesicles formed of fatty acids , monoglycerides , glycerol and bile salts

Question 25

what do micelles do ?

Answer 25

deliver the fatty acids , glycerol and monoglcerides to the epithelial cells of ileum for absorbtion

Question 26

where are the products of digestion absorbed ?

Answer 26

across cells lining the ileum

Question 27

what is the ileum cell wall covered in ?

Answer 27

villi

Question 28

how are villi adapted for absorbtion ?

Answer 28

thin walls
surronded by capillary network
epithelial cells have microvilli
increases surface area,decreases diffusion distance and maintains a concentration gradient

Question 29

what method are monosaccarrides and amino acids absorbed in ?

Answer 29

co transport

Question 30

what does there need to be in order for glucose and amino acids to be be absorbed from the lumen to the gut facillitated diffusion ?

Answer 30

a higher concertration in the lumen compared to the epithelial cells

Question 31

why can’t glucose and amino acids be absorbed from the lumen to the gut through facillitated diffusion ?

Answer 31

their is usually a higher concetration of them in the epithelial cells compared to the lumen .

Question 32

how do sodium ions move from epithelial cells to blood ?

Answer 32

active transport

Question 33

why do sodium ions move from epithelial cells to blood ?

Answer 33

lower concentration in epithelial cells compared to lining of ileum .So sodium ions can diffuse from the ileum down the concentration gradient into the epithelial cells

Question 34

what type of protein do sodium ions diffuse through?

Answer 34

co transport protein

Question 35

what does the sodium ion co transport protein allow?

Answer 35

either glucose or amino acid can attach and are transported into the epithelial cell against their concentration gradient.so glucose has a high concentration in epithelial cell and moves by facillitated diffusion into the blood

Question 36

how are lipids absorbed

Answer 36

encouters ileum epithelial cells fatty acids and monoglycerides can simply diffuse across the cell membrane to enter the epithelial cells

Question 37

what happen to monoglycerides ,fatty acids and glycerol once inside the epithelial cell ?

Answer 37

modified back into triglycerides by endoplasmic recticulum and golgi body

Question 38

what is it called when the products of lipids are being processed by the golgi body and bind to a protein ?

Answer 38

chylomicrons

Question 39

where a chylomicrons released

Answer 39

golgi vesicles

Question 40

what do golgi vesicles containing chylomicrons do ?

Answer 40

move to other end of epithelial cells and releases by exocytosis

Question 41

how are what gets released from a golgi vesicle in lipid absorbtion absorbed into rest of body ?

Answer 41

absorb into lacteal and get transported round in lymph vessel which eventually gets drained into cappillary system