b2 organisation

Question 1

define tissue

Answer 1

a group of cells with similar structure working together for a specific function

Question 2

define organ

Answer 2

a group of tissues working together for specific functions

Question 3

order the following : organ cell tissue organism organ systm

Answer 3

cell

Question 4

state the function of the salivary glands

Answer 4

produce digestive enzymes(e.g amylase)

Question 5

name the tube that carries food from the mouth to the stomach

Answer 5

oesophagus/gullet

Question 6

state the function of the stomach

Answer 6

releases digestive enzymes to digest food

Question 7

state the function of the liver in the digestive system

Answer 7

produces bile for lipid digestion

Question 8

state the function of the small intestine

Answer 8

digest food and absorb nutrients from digested food

Question 9

state the function of the large intestine

Answer 9

absorb water from digested food

Question 10

state the function of the pancreas

Answer 10

produces/releases digestive enzymes

Question 11

state the function of the gall bladder

Answer 11

stores bile before releasing into small intestine

Question 12

what are carbohydrates made of

Answer 12

simple sugars

Question 13

state the chemical formula of glucose

Answer 13

C6H12O6

Question 14

name a complex carbohydrate that is made up of glucose

Answer 14

starch/cellulose/glycogen

Question 15

state the importance of having carbohydrates in our diet

Answer 15

energy source - break down glucose in respiration to release energy for metabolic reactions

Question 16

what are lipids made up of?

Answer 16

1 glycerol + 3 fatty acids

Question 17

state the importance of having lipids in our diet

Answer 17

energy store/make up cell membrane/steroid hormones

Question 18

what are proteins made up of

Answer 18

amino acids

Question 19

state the importance of having proteins in out diet

Answer 19

structural components/hormones/antibodies/enzymes

Question 20

name the reagent used to test for starch

Answer 20

iodine

Question 21

what is a positive result for starch test?

Answer 21

starch turns iodine from brown-red to blue black

Question 22

name the reagent used to test for sugars

Answer 22

benedict’s solution

Question 23

what is the positive result for sugars

Answer 23

benedict’s solution turns from clear blue to brick red

Question 24

what is the reagent used to test for proteins

Answer 24

biuret solution

Question 25

what is the positive test for proteins

Answer 25

biuret turns from blue to purple

Question 26

what is the reagent used to test for lipids

Answer 26

Ethanol(+water)

Question 27

what is the positive test for lipids?

Answer 27

white milky layer

Question 28

state a hazard in doing food tests

Answer 28

ethanol is flammable/biuret is corrosive

Question 29

define catalyst

Answer 29

A substance that speeds up chemical reactions but dont get used up

Question 30

define enzymes

Answer 30

biological catalysts that speeds up chemical reactions

Question 31

what kind of molecule are enzymes - carbohydrates, lipids or proteins?

Answer 31

proteins

Question 32

define active site

Answer 32

the site on an enzyme where the substrate binds

Question 33

Any substance can fit into the active site of an enzyme?True or False?

Answer 33

False

Question 34

briefly describe the lock and key model

Answer 34

substrate fits into the active site to form enzyme-substrate complex, reaction occurs, enzyme releases products and binds to another substrate

Question 35

define metabolism

Answer 35

sum of all reactions in a cell/body

Question 36

how does temperature affect enzymes rate of reaction?

Answer 36

as temperature increases, rate of reaction increases until after optimum

Question 37

why do enzymes stop working past their optimum temperature

Answer 37

they become denatured(substrate can no longer bind to active site

Question 38

why do enzymes not work well at lower temperature?

Answer 38

inactive(not enough kinetic energy to collide and bind to active site)

Question 39

how does a change in pH affect enzyme structure?

Answer 39

pH change affects forces holding enzyme structure together, causing it to denature

Question 40

define digestion

Answer 40

breakdown of large insoluble molecules into smaller soluble substances

Question 41

name the type of enzyme that digest carbohydrates

Answer 41

carbohydrates

Question 42

name the enzyme that digest starch

Answer 42

amylase

Question 43

name the enzyme that digest starch

Answer 43

amylase

Question 44

name the product of the breakdown of starch

Answer 44

simple sugars

Question 45

name the type of enzyme that digests proteins

Answer 45

proteases

Question 46

name the protease that works well in the stomach

Answer 46

pepsin

Question 47

name the product of the breakdown of proteins

Answer 47

Amino acids

Question 48

name the type of enzyme that digests lipids

Answer 48

lipases

Question 49

name the products of the breakdown of lipids

Answer 49

Glycerol and fatty acids

Question 50

which organs produce amylase

Answer 50

salivary glands, pancrease and small intestine

Question 51

which organs produce proteases

Answer 51

stomach,pancrease and small instine

Question 52

which organs produce lipases

Answer 52

pancreas and small intestine

Question 53

where does starch digestion occur

Answer 53

mouth + small intestine

Question 54

where does protein digestion occur

Answer 54

stomach + small intestine

Question 55

where does lipid digestion occur

Answer 55

small intestine

Question 56

how are the nutrients carried away from the gut

Answer 56

absorbed into bloodstream through small intestine

Question 57

state an observation to determine when the amylase has completed its digestion of starch

Answer 57

Iodine remains brown-red rather than turing blue-black

Question 58

state a reason for setting the amylase solution,starch solution and the buffer in the water bath before the experiment

Answer 58

To ensure all of the same temp, so that temperature will not affect the results(fair test)

Question 59

How does the hydrochloric acid in the stomach help with digestion

Answer 59

provides optimum pH for pepsin to digest proteins

Question 60

Apart from digestion, what is another function of hydrochloric acid in the stomach

Answer 60

Kill pathogens in food

Question 61

How is the stomach adapted to protect itself from the hydrochloric acid?

Answer 61

Thick mucus layer/quick renewal of epithelial layer

Question 62

state 2 functions of bile

Answer 62

emulsifies fats, neutralises acidic food from stomach

Question 63

what is emulsification?

Answer 63

Physically breaking down large oil drops into smaller droplets, increasing surface area for lipase to work on.

Question 64

bile is an enzyme TRUE or FALSE?

Answer 64

False

Question 65

Hydrochloric acid in the stomach breaks down food.True or false?what does it do?

Answer 65

False - provides optimum pH for pepsin and kills bacteria,NOT digest food

Question 66

state the importance of the neutralising role bile has.

Answer 66

small intestine does not have protective mucus layer, enzymes will denature in small intestine