Enzymes

Question 1

Explain how enzymes are specific to the exact sequence of DNA bases [2]

Answer 1

base sequence and active site complementary
ref. to active site

Question 2

Describe how the biological washing powder removes egg stains [3]

Answer 2

protease
chemical digestion
digested to amino acids
insoluble to soluble molecules

Question 3

Explain why the washing powder works best at 30 degrees and should NOT be used above 50 degrees [4]

Answer 3

enzymes have specific shape
ref. to active site
30 optimum temp
above 50 enzymes denature
active site changes shape
below 30 less ke

Question 4

Outline the roles of bile [4]

Answer 4

emulsification
increased surface area of fat gloulese
faster digestion
by lipase
neutralises stomach acid
denatures pepsin

Question 5

Explain why temp has an effect on the rate of photosynthesis [4]

Answer 5

enzymes
increase in temp increases rate
increases ke of molecules
increases effective collisions between enzymes and substrate
reaction will have optimum temp
increases rate of diffusion
increased uptake of co2 molecules into leaf

Question 6

Explain why the rate of photosynthesis decreases if humidity decreases [3]

Answer 6

air dry
ref to increasing diffusion gradient
from air spaces into leaf to air surrounding leaf
increased rate of transpiration
stomata close
co2 cannot enter

Question 7

State two factors other than ph that would affect enzyme activity [2]

Answer 7

temp
conc of substrate