Key Area 4: Proteins and Enzymes

Question 1

Proteins functions?

Answer 1

Structural, enzymes, antibodies, membrane receptors

Question 2

Proteins

Answer 2

Folded up amino acid chains that have many different functions in the body

Question 3

Amino acids

Answer 3

Fundamental molecules that make up proteins

Question 4

Structural proteins

Answer 4

proteins that help living organisms maintain their shape and structure

Question 5

Enzyme

Answer 5

are proteins, act as biological catalysts to speed up chemical reactions in cells. remain unchanged

Question 6

Hormone

Answer 6

Carry specific messages in the bloodstream of living organisms

Question 7

Antibodies

Answer 7

Provide specific defence against body invaders such as certain bacteria and viruses

Question 8

Receptors

Answer 8

Allow cells to recognise specific substrates

Question 9

Biological catalyst

Answer 9

a protein that speeds up a specific chemical reaction in a cell and remains unchanged

Question 10

Active site

Answer 10

where substrate molecules attach to their specific enzyme

Question 11

Substrate

Answer 11

the chemicals that an enzyme reacts with

Question 12

Enzyme-substrate complex

Answer 12

enzyme and substrate fit tightly together in the active site

Question 13

Product

Question 14

The active site of an enzyme has a …. shape because each has a ….. substrate which it can act with

Answer 14

Specific

Question 15

Degredation

Answer 15

is the breaking down of large molecules into smaller ones

Question 16

Synthesis

Answer 16

Is building up a large molecule from smaller ones

Question 17

Optimum

Answer 17

the conditions that are most favorable for an enzyme to be active

Question 18

Denatured

Answer 18

The enzyme will not be able to attach to it’s substrate anymore

Question 19

When the active site changes shape this means that the enzyme has become

Answer 19

Denatured

Question 20

Enzyme action results in

Answer 20

products

Question 21

Enzymes can be involved in

Answer 21

degradation and synthesis

Question 22

The shape on an active site is determined by the sequence of and bonding between

Answer 22

amino acids

Question 23

The active site is … to the substrate molecule

Answer 23

Specific (complementary)

Question 24

Factors that affect enzyme activity

Answer 24

Temperature, pH

Question 25

How does temp. affect enzyme activity

Answer 25

e are inactive at low temps. as temp increases they move more and rate of reaction increases

Question 26

At high temps the shape of the active site

Answer 26

becomes altered and the enzyme is denatured

Question 27

how does pH affect enzyme activity

Answer 27

e work best at their optimum pH. If pH is to low or too high the enzyme becomes denatured

Question 28

A control copy of the experiment

Answer 28

where all factors are kept the same but the independent variable is changed

Question 29

Enzyme experiments can investigate the effect of … on the rate of reaction

Answer 29

temp, pH, substrate concentration and enzyme concentration