3.3 Organisms exchange substances with their environment

Question 1

what are large biological molecules broken down into

Answer 1

smaller molecules

Question 2

what is the role of digestion

Answer 2

breaks larger molecules into smaller molecules

Question 3

where is amylase produced

Answer 3

-salivary glands
- pancreas

Question 4

where is amylase released

Answer 4

into the mouth
into the small intestine

Question 5

what does amylase hydrolyse starch into

Answer 5

maltose

Question 6

what does starch get hydrolysed into

Answer 6

maltose

Question 7

where are membrane bound disaccharides found

Answer 7

attached to the epithelial cells lining the ileum of the small intestine

Question 8

what does maltase hydrolyse maltose into

Answer 8

glucose and glucose

Question 9

what does sucrase hydrolyse sucrose into

Answer 9

fructose and glucose

Question 10

what does lactase hydrolyse lactose into?

Answer 10

galactose and glucose

Question 10

where are bile salts produced

Answer 10

liver

Question 11

what do bile salts do

Answer 11

the emulsify lipids into smaller droplets

Question 12

what do small lipid droplets provide

Answer 12

• they increase the surface area of lipids
  -speeds up the action of lipase

Question 13

where is lipase made

Answer 13

pancreas

Question 14

where is lipase released

Answer 14

the small intestine

Question 15

what does lipase hydrolyse lipids into

Answer 15

monoglycerides + fatty acids

Question 16

what bonds do lipase break

Answer 16

ester bonds

Question 17

what components form micelles

Answer 17

monoglycerides
fatty acids
bile salts

Question 18

what do monoglycerides, faaty acids and bile salts stick together to form

Answer 18

micelles

Question 19

what is the role of endopeptidases

Answer 19

-hydrolyse peptide bonds within a protein.
- breaks proteins into 2 or smaller peptides

Question 20

what is the role of exopeptidases

Answer 20

hydrolyse peptide bonds at the end of proteins
removing an amino acid

Question 21

what is the role of dipeptidases

Answer 21

hydrolyse peptie bonds between a dipeptide

Question 22

where is dipeptidases found

Answer 22

membrane bound in ileum

Question 23

describe where the concentration gradient established when sodium is actively pumped out of the cell into the blood

Answer 23

high concentration of sodium in lumen than epithelial cells.

Question 24

describe where the concentration gradient is established when glucose is co-transported from the lumen into the epithelial cells

Answer 24

higher concentration of glucose in epithelial cell than blood

Question 25

describe the mechanism of the absorption of micelles

Answer 25

• monoglycerides and fatty acids diffuse out of micelles into epithelial cells . [lipids are soluble]
• monoglycerides and triglycerides recombine to triglycerides which aggregate into globules.
• globules coated to form chylomicrons

Question 26

gobulars coated with proteins are called….

Answer 26

chylomicrons

Question 27

what do micelles contain

Answer 27

bile salts
fatty acids
monoglycerides

Question 28

describe the process involved in he absorption and transport of digested lipid molecules from the ileum into lymh vessels

Answer 28

micelles contain bile salts and lipids
they bring/release fatty acids/monoglycerides to the cells lining the lumen
fatty acids are absorbed by diffusion
triglycerides are formed
vesicles move to the membrane

Question 29

where does digestion occur

Answer 29

small intestine