Paper 1 Exam Questions Flashcards
Some of the leaves from the gardener’s strawberry plant die.
The dead leaves fall off the strawberry plant onto the ground.
The carbon in the dead leaves is recycled through the carbon cycle.
Explain how the carbon is recycled into the growth of new leaves.
statements:
- (carbon compounds in) dead leaves are broken down by microorganisms / decomposers / bacteria / fungi
- photosynthesis uses carbon dioxide
explanations:
- (microorganisms) respire
- (and) release the carbon from the leaves as carbon dioxide
- plants take in the carbon dioxide released to use in photosynthesis to produce glucose
use of carbon in growth:
- glucose produced in photosynthesis is used to make amino acids / proteins / cellulose
- (which are) required for the growth of new leaves
RULER DROP TEST
Suggest two ways the students could improve the method to make sure the test would give valid results. [2 marks]
- drop the ruler from the same height each time
- let the ruler drop without using any force
- same weight of ruler
- thumb should be same distance from the ruler each time
- use the same hand to catch the ruler each time
- carry out the experiment with the lower arm resting in the same way on the table
The students then measured Student A’s reaction time using a computer program. This is the method used.
- The computer shows a red box at the start.
- As soon as the box turns green the student has to press a key on the keyboard as fast as possible.
- The test is repeated five times and a mean reaction time is displayed. Student A’s mean reaction time was 110 ms. Using a computer program to measure reaction times is likely to be more valid than the method using a dropped ruler. Give two reasons why.
no indication beforehand when the colour will change
or
you might be able to tell when the person is about to drop the ruler
measurement of time is more precise (than reading from a ruler)
or
resolution (of computer timer) is higher
The conclusion in the newspaper might not be correct.
Suggest two reasons why.
aboriginal people can eat other foods (so they may not be in food insecurity)
we do not know if other (traditional) food sources have declined
A blood test called the glucose tolerance test checks how well the body processes glucose. Concentrations of glucose in the blood are measured before and after drinking a glucose drink.
Patients are not allowed to eat food for 8 hours before the glucose tolerance test.
Suggest why patients are not allowed to eat for 8 hours before the test. [1 mark]
results not affected by glucose from food
or 8 hours is sufficient time for insulin to have acted on any glucose from food eaten
or so that there is a low starting point to show the effect
Hyperthyroidism is caused by an overactive thyroid gland.
Suggest what would happen in the body of a person with hyperthyroidism.
too much thyroxine is released into the blood
which raises BMR causing increase in formation of glycogen / lipids / proteins
or
increase in rate of respiration
or
increase in breakdown of excess proteins
Suggest two reasons why the different types of milk took different lengths of time to reach pH 5
- different concentration / type of fat / lipid
- different concentration / type of proteins / carbohydrate / sugar
- different (amount / type of) bacteria present
- may have been pasteurised by a different process
- different starting pH
Farming techniques have changed in recent years.
Describe:
- why more land is being used for farming
- how increased farming has decreased biodiversity. [6 marks]
The length of a DNA double helix increases by 0.34 nm for every pair of nucleotides.
The total number of nucleotides in a human body cell is 1.2 × 1010.
Calculate the total length of double helix in a human body cell. Give your answer in metres. Use information from Figure 5
Explain how making dog food from insects could improve human food security in the future.
less land required
(so) more space for crops (for humans)
less methane (from animals) therefore less global warming (therefore)
less harmful effects of global warming on (human) food production
Give two possible effects of an increase in global air temperature on living organisms
- (some) plants grow faster / higher yield
- loss of habitat
- migration or change in distribution
- extinction
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
cells / liver / muscles absorb less glucose
(so) glucose concentration in blood remains high
(high blood glucose stimulates / causes) pancreas to release more insulin
