Corrections

Question 1

Why are samples squashed hard and not pushed sideways

Answer 1

Squash and flatten cells so thin

Stops cells rolling or breaking chromosomes

Question 2

How does chromosome action lead to differences in DNA per cell in meiosis

Answer 2

DNA replicated = 4AU
Homologous chromosomes separate = 2AU
Sister chromatids separate = 1AU

Question 3

What does ribosome allow to happen in terms of tRNA

Answer 3

Allows tRNA with antibodies to bind and associate

So can catalyse peptide bonds between amino acids held by tRNA

Question 4

What happens to the protein in co transport

Answer 4

Conformational change in shape to move molecules

Question 5

High salt concentration does what to blood pressure

Answer 5

Increases it

Meaning more fluid pushed out at the arteriole end of capillary

Question 6

Why does increasing temperature denatured enzymes

Answer 6

Increased kinetic energy
Increases vibrations
Hydrogen bonds broken
Active site no longer complementary
Less ESC per second

Question 7

Purpose of dipeptidases

Answer 7

Hydrolyse peptide bonds to release amino acids
Which can cross cell membranes
Since dipeptides cannot

Question 8

3 comparisons of genetic diversity

Answer 8

Base sequence of DNA
Base sequence of amino acids/proteins
Base sequence of mRNA

Question 9

Tracheal system adaptations

Answer 9

Tracheoles have thin walls so short diffusion distance to cells
Tracheoles highly branched/large numbers so short diffusion distance to cell
Tracheoles highly branched/large so large surface area for gas exchange
Trachea provide tubes full of air for fast diffusion
Fluid in ends of tracheoles moves out into tissues during exercise means faster diffusion through air to gas exchange surface
Body can be moved by muscles yo move air so maintains a diffusion concentration gradient for oxygen/carbon dioxide

Question 10

TEM vs optical

Answer 10

TEM uses electrons, optical uses light
TEM allows a greater resolution
So smaller organelles can be observed
TEM must be dead specimens but optical can view live ones
TEM does not show colour but optical does
TEM requires thinner specimens
TEM has a more complex staining process/preparation
TEM focuses using magnets but optical uses glass lenses

Question 11

How do you measure size

Answer 11

Mass not area

Question 12

Optical microscope issue detecting small organelles

Answer 12

Low resolution

Wavelength is too large