!! 4.2.2.1, Digestive System

Question 1

what is an organ system

Answer 1

a group of organs that work together to perform a particular role

Question 2

which 5 organs make up the digestive system

Answer 2

small intestine

large intestine

liver

glands

stomach

Question 3

what does the small intestine do in the digestive system

Answer 3

digests food and absorbs soluble food molecules

Question 4

what does soluble mean

Answer 4

can be dissolved

Question 5

what does unsoluble mean

Answer 5

can’t be dissolved

Question 6

what does the large intestine do in the digestive system

Answer 6

absorbs water molecules from remaining undigested food

this allows it to produce faeces

Question 7

what does the liver do in the digestive system

Answer 7

produces bile

Question 8

what do glands do in the digestive system

Answer 8

produce digestive juices

Question 9

2 examples of glands in the digestive system

Answer 9

pancreas

salivary glands

Question 10

what does the stomach do in the digestive system

Answer 10

digests food

Question 11

what is an organism

Answer 11

highest level of organisation in a multicellular organism

and consists of several organ systems

Question 12

what are levels of organisation in multicellular organisms, starting least complex

Answer 12

cell

tissue

organ

organ system

organism

Question 13

what is an organ

Answer 13

a group of distinct tissues that group together to form a specific function

Question 14

2 factors that affect rate of enzyme reactions

Answer 14

temperature

PH

Question 15

how does temperature affect the rate of enzyme action

Answer 15

increasing the temperature of a working enzyme initially increases the reacting activity

enzymes have an optimum temperature, once reached their activity decreases

past a certain temperature, the active site changes shape, and the enzyme is denatured (loses its catalytic activity).

Question 16

how does PH affect the rate of enzyme action

Answer 16

Enzymes have an optimum PH level

changes away from the optimum PH, then the enzyme activity decreases

PH is too low or too high the enzyme is denatured and will not function

Question 17

does is the ‘lock and key’ theory

Answer 17

the active site is like a lock and the substrate is like a key

usually only one enzyme for every substrate (or one key for each lock)

Question 18

what do enzymes do to reactions in the body

Answer 18

speeds them up

often called ‘biological catalysts’

Question 19

what is the rate of reaction equal to on a graph

what does it show

Answer 19

the gradient

shows mass of the product, plotted against the reaction time

Question 20

how is the rate of reaction calculated using a graph

Answer 20

(using the gradient)

picking two points on the graph

then dividing the change in mass by the change in time

Question 21

what must happen in order for an enzyme to catalyse a reaction

how does this happen

Answer 21

the reacting chemical (substrate) must bind to the enzyme’s active site

both the substrate and the active sight are the same shape

lock and key theory

Question 22

unit for rate of reaction

Answer 22

g/s

Question 23

where are digestive enzymes made

and by who

Answer 23

specialised cells in the glands and the lining of the gut

Question 24

what do digestive enzymes do in the body

Answer 24

speed up the breakdown of large, insoluble food molecules into smaller, soluble ones

that are then small enough to be absorbed into the bloodstream

Question 25

how can digested molecules be used what happens to some of the glucose produced by digestion

Answer 25

to construct new carbohydrates, proteins and lipids in the body some is used for respiration

Question 26

what are the three main digestive enzymes

Answer 26

amylase lipids protease

Question 27

what does the digestive enzyme amylase do

Answer 27

breaks down starch into simple sugars, predominantly maltose

Question 28

what do carbohydrases example of a carbohydrase

Answer 28

break down carbohydrates into simple sugars amylase

Question 29

which three places is amylase produced

Answer 29

small intestine pancreas salivary glands

Question 30

what are the two sites of action for amylase

Answer 30

small intestine mouth

Question 31

constituent

Question 32

what does the digestive enzyme protease do

Answer 32

breaks down proteins into amino acids

Question 33

which three places is protease produced

Answer 33

small intestine pancreas stomach

Question 34

what are the two sites of action for protease

Answer 34

stomach small intestine

Question 35

what does the digestive enzyme lipase do

Answer 35

breaks down lipids into glycerol and fatty acids

Question 36

is bile alkaline or acidic

Answer 36

bile is an alkaline substance

Question 37

where is bile produced where is bile stored

Answer 37

produced in the liver stored in the gall bladder

Question 38

what does bile do in the digestive system

Answer 38

breaks up fats into tiny droplets, through emulsification the tiny droplets have a higher surface area than the original fat drop the alkaline condition and larger SA increases the rate of fat breakdown by lipase

Question 39

what is emulsification

Answer 39

process by which bile breaks up fats into tiny droplets

Question 40

in which condition to enzymes in the small intestine operate

Answer 40

in alkaline conditions

Question 41

in which condition to enzymes in the small intestine operate

Answer 41

in alkaline conditions

Question 42

which role does bile play in the stomach

Answer 42

Bile neutralises hydrochloric acid from the stomach to stop enzymes in the small intestine becoming denatured

Question 43

what is meant by an enzyme being denatured

Answer 43

it's active site has changed shape

Question 44

equation for rate of reaction

Answer 44

change in mass / change in time