exam qs

Question 1

how is energy for the photosynthesis reaction gained by plants

Answer 1

light is captured and absorbed by chlorophyll

Question 2

How are human lungs adapted for efficient gas exchange`

Answer 2

-many alveoli which increase surface area
-capillaries are thin which provide a short diffusion path
-breathing moves air in and out
-large capillary network around alveoli removes oxygenated blood quickly

Question 3

Describe what happens during each stage of the cell cycle

Answer 3

1. DNA and chromosomes replicate. sub-cellular structures replicate
2. one set pf chromosomes is moved to each end of the cell
3. cytoplasm and cell membrane divide to form 2 identical daughter cells

Question 4

Why will a leaf in the light for 4 days contain glucose and starch

Answer 4

glucose from photosynthesis and excess glucose converted to starch

Question 5

WHy does a lead left in a cupboard with no light for 2 days contain glucose but not starch

Answer 5

starch stores have been converted to glucose
so glucose can be used to release energy because there is no light to make more glucose by photosynthesis

Question 6

suggest why nodules on a gorse plant benefit the bacteria that live on them

Answer 6

the bacteria obtain glucose from the plant
glucose is used for resiration

Question 7

WHy do nodules benefit the gorse plant

Answer 7

gorse plant obtains nitrate ions
needed for amino acids.

Question 8

describe the effects of liver failure on the body

Answer 8

> no bile made in the liver
-fats are not emulsified
lactic acid not broken down
proteins are not broken down
toxins like alcohol aren’t removed
glycogen stores are not formed

Question 9

Describe how Monoclonal antibodies and a fluorescent dye could be used to seed pathogens on a microscope slide

Answer 9

bind the dye to the monoclonal antibodies
put bound dyed monoclonal antibodies on the slide and rinse off
the mAbs will bind to the pathogens and show up under the microscope

Question 10

explain how the phagocytosis of pathogens will help patients

Answer 10

pathogens will be engulfed by phagocytosis therefore there is less damage to tissue

Question 11

how should clinical trials for a monoclonal antibodies trial be done

Answer 11

-first given to healthy volunteers at a low dose to see if it’s safe
-then give to patients woth the disease to check for the correct dosage and see side effects
-trial on lots of people

Question 12

why are monoclonal antibodies more successful in treating human disease than mabs made using mice

Answer 12

the body is less likely to reject the mAbs
-mouse mAbs are more likely to be rejected
-the human lymphocytes have already responded to that infection