B3

Question 1

mouth function

Answer 1

salivary glands are triggered by the smell of food to create saliva, containing enzyme amylase. this chemically breaks down food

Question 2

mechanical digestion

Answer 2

chewing

Question 3

oesophagus function

Answer 3

muscular tube that carries food to the stomach. food is pushed through by a series of contractions called peristalsis

Question 4

pancreas function

Answer 4

makes digestive enzymes, which are secreted into the first segment of the small intestine. also produces enzyme insulin, which goes into the bloodstream

Question 5

gall bladder function

Answer 5

stores excess bile before releasing it into the small intestine

Question 6

liver function

Answer 6

processed absorbed food and detoxifies the blood, producing bile

Question 7

stomach function

Answer 7

contains hydrochloride acid to kill ingested bacteria. muscular walls contract to churn food

Question 8

small intestine function

Answer 8

produces protease, amylase and lipas enzymes. soluble products are absorbed into blood through the walls, which are covered in villi

Question 9

villi

Answer 9

hair-like projections that line the inside of the small intestine

Question 10

large intestine function

Answer 10

connects the small intestine to the rectum. highly specialised organ that processes waste. absorbs water into the blood as stool passes through

Question 11

rectum function

Answer 11

receives stool, holds until evacuation

Question 12

anus function

Answer 12

final part of digestive tract

Question 13

benedict’s test for glucose

Answer 13

colour when benedict’s solution is added:
blue - none
green - traces
orange - moderate
brick red - large

Question 14

Biuret test for protein

Answer 14

turns purple when biuret reagent is added if protein is present

Question 15

emulsion test for lipids

Answer 15

turns milky when ethanol and water are added if lipids are present

Question 16

iodine solution test for starch

Answer 16

turns blue-black when iodine solution is added if starch is present

Question 17

enzyme function

Answer 17

biological catalyst that break down food

Question 18

denatured

Answer 18

the breakdown of the molecular structure of a protein so it no longer functions

Question 19

what is a protein molecule made of

Answer 19

long chains of amino acids joined by special bonds. these bonds are sensitive to temperature and pH and can be easily broken

Question 20

carbohydrate enzyme

Answer 20

amylase

Question 21

protein enzyme

Answer 21

protease

Question 22

fats enzyme

Answer 22

lipase

Question 23

what are enzymes made of

Answer 23

protein

Question 24

lock and key hypothesis

Answer 24

the active site must be complimentary to the shape of the substrate molecule. lock- enzyme
key - substrate molecule

Question 25

optimum temperature for enzyme reactions

Answer 25

37°

Question 26

denatured cell

Answer 26

if the temperature is above the optimum. the enzyme changes shape and the active site no longer has a complimentary shape to the substrate molecule

Question 27

why is having a high temperature dangerous

Answer 27

the body’s enzymes become denatured so they can’t function properly, resulting in death

Question 28

what are enzymes made out of

Answer 28

protein

Question 29

amylase function

Answer 29

converts starch to sugar