DIGESTION OF CARBOHYDRATES

Question 1

FUNCTION OF THE MOUTH

Answer 1

where food enters the body known as ingestion

Question 1

function of salivary glands

Answer 1

produce saliva which lubricates food and contains amylase for starch digestion

Question 1

function of the epiglottis

Answer 1

prevents swallowed food from entering the lungs

Question 1

function of the esophagus

Answer 1

food travels down here by peristalsis to the stomach

Question 1

function of the stomach

Answer 1

food is mixed here with acid and enzymes that digest protein in the food

Question 2

function of the small intestine

Answer 2

food is further digested in the first part and then absorbed into blood in the last part

Question 3

function of the large intestine

Answer 3

reabsorption of water and water-soluble vitamins and minerals
faces are formed

Question 4

function of the rectum

Answer 4

storage of faces before egestion

Question 5

function of anus

Answer 5

where faces are expelled from the body

Question 6

function of the liver

Answer 6

produces bile which is involved in lipid digestion (emulsification)

Question 7

function of the gall bladder

Answer 7

stores bile, which is involved in lipid digestion (emulsification)

Question 8

function of the pancreas

Answer 8

produces digestive enzymes and alkali which are secreted into the small intestine

Question 9

definition of digestion

Answer 9

process in which large molecules are hydrolysed by enzymes into small molecules which can be absorbed and assimilated

Question 10

what is the physical breakdown

Answer 10

large food molecules broken down into smaller pieces by teeth.
allows ingestion
provides larger surface area for chemical digestion
food churned by muscles in stomach wall

Question 11

what is chemical breakdown

Answer 11

hydrolysis of large insoluble molecules into smaller soluble ones using enzymes

Question 12

three digestive enzymes

Answer 12

carbohydrase’s
lipases
proteases

Question 13

what is the duodenum

Answer 13

first and shortest segment of the small intestine
receives partially digested food (chyme) from the stomach
recieves bile from the gallbladder and digestive enzymes from the pancreas
vital role in chemical digestion

Question 14

what is the ileum

Answer 14

produces enzymes in its walls and has them secreted in by glands
inner walls folded into villi which are further folded into microvilli
increases surface area available for absorption

Question 15

carbohydrate digestion

Answer 15

food is chewed to make molecules smaller and provide a larger surface area for enzymes
saliva mixed during chewing. salivary amylase hydrolyses any starch to maltose. saliva contains mineral salts to maintain a neutral pH
food enters the stomach where conditions are too acidic which denatures the amylase
pancreatic juice contains pancreatic amylase and alkaline salts to maintain a neutral pH
food is passed into the small intestine where it mixes with pancreatic juice
muscles in the intestinal wall push the food along the ileum
epithelial lining of the ileum produces maltase which remains a part of the cell surface membrane of the epithelial cells (membrane bound disaccharides)

Question 16

what does amylase do

Answer 16

hydrolyses alternate glycosidic bonds of the starch molecule which produces the disaccharide maltose which is further hydrolysed into alpha glucose by maltase

Question 17

describe the steps of the co transport of glucose

Answer 17

1. sodium ions actively transported out of epithelial cells into the capillary, whilst potassium ions are pumped in
2. causes there to be a lower conc of sodium in the epithelial cell
3. high conc of sodium in the lumen of the si
4. sodium ions use facilitated diffusion to diffuse into the epithelial cell
5. a glucose molecule is also brought into the epithelial cell
6. glucose molecule (high conc in the epithelial cell compared to capillary), is moved out of the epithelial cell into the capillary via facilitated diffusion