Paper 2 Exam Qs Flashcards
(6 cards)
Explain why more water was lost through the skin during the race.
[2 marks]
- (more) sweating
- (because) exercise releases
heat
Explain why more water was lost by breathing during the race.
[3 marks]
- more energy needed
- (so) more (aerobic) respiration
- (so) increased breathing (rate /depth) (to supply oxygen or
remove carbon dioxide / water)
A large amount of untreated sewage entered the river. Many fish died.
Untreated sewage contains organic matter and bacteria.
Explain why many fish died.
[5 marks]
- bacteria decay organic matter
- by digestion
- (and) bacteria respire aerobically
- (which) lowers oxygen
concentration (in water) so fish have less oxygen - (so) reduced energy supply
causes death of fish
The scientists want to produce a type of cattle that makes large volumes of low-fat milk.
The scientists will selectively breed some of the animals shown in Figure 11.
Describe how the scientists would do this.
[4 marks]
- find female with low(est) fat in milk and high(est) milk yield
- find male whose female offspring have high(est) milk yield and low(est) fat in milk
- cross the best (for both features) female with the best male
- select best offspring (for both features) from each generation and repeat for several
generations
A man is walking across a desert.
The man has used up his supply of drinking water.
Explain how the gland you named in Question 06.1 and the kidneys reduce
water loss.
[3 marks]
- high(er) concentration of blood causes (more) ADH / hormone release
- (and hormone / ADH causes) increased permeability of kidney tubules (to water)
- (so) increased water reabsorption
The body cells of a person with Type 2 diabetes do not respond to insulin.
A person with Type 2 diabetes often has a higher blood insulin concentration than a non-diabetic person.
Explain why.
[3 marks]
- cells absorb less glucose
- (so) glucose concentration in blood remains high
- (high blood glucose stimulates / causes) pancreas to release more insulin
