Paper 1 questions to memorise

Describe what happens during each stage of the cell cycle:

Stage 1:

Stage 2:

Stage 3:

Stage 1: longest - chromosomes thicken and replicate

Stage 2 - chromosomes line up in middle and pulled to opposite sides of nucleus/ cell

Stage 3 - cytokinesis occurs and the cell splits into 2 genetically identical cells.

• shows that the enzyme and substrate are complementary in shape to each other.

• Shows substrate is broken down into products

• Shows that the enzyme has not changed.

Describe how the students would find out if the liquid from the leaf contained glucose.

• place liquids into separate test tubes labelling them.

• add same volume of benedict’s solution to each

• put in water above 65 degrees Celsius or above.

• If turned brick red, it contains glucose.

Explain why the leaf left in a cupboard with no light for two days did contain glucose but did not contain starch.

• The starch converted to glucose

• As there was no light for photosynthesis to make more glucose.

What does a magnesium deficiency mean in plants?

• causes insulin resistance so can’t take in glucose

• Causes impairment in growth and discolouration.

• Presence of aphids

• Infected by another disease

• Lack of available light

• Magnesium deficiency

a. suggest how the nodules benefit the bacteria

provides glucose for respiration

b. explain how the nodules benefit the gorse plant.

nodules provide nitrate ions which is needed to make amino acids in the plant.

Age and gender were two factors controlled.

many other factors were involved

suggest two other factors which the scientists would have controlled.

• diet

• smoking habits

• medication

• family history of (liver) disease

read all the info given for questions when suggesting why it is valid/ not valid.

read all the info given for questions when suggesting why it is valid/ not valid.

Describe the effects of liver failure on the body

• fats may not be properly digested as there would be no bile to emulsify/ break it down.

• Liver can no longer break down toxins like alcohol.

• Glycogen stores may not be formed.

• Protein/ amino acids may not be broken down and deaminated.

A person with AIDS may take longer than a healthy person to recover from a Salmonella infection.

Explain why - 2 marks

• Immune system is damaged with AIDS due to the immunosuppressants in medication.

• White blood cells can’t kill bacteria as effectively.

What measurement would the scientist need to take to calculate the area where no bacteria were growing?

radius/ diameter

Give one change to the experiment that would allow the scientists to check if the results are repeatable.

Repeat and look to see if results are similar.

• Toxicity/ side effects

• Effect on other types of pathogens

• Ease of use

1. 2 groups of people —> non-smokers and smokers

   • Have at least 5 people in each group

2. Get each person to perform a named excersise.

Control variables:

• Same number of ppl in each group

• same gender

• same intesnity of excersise

• same type of excersise

• same age

3. Record heart rate for each person before and after excersise.

4. Calculate increase in heart rate for each person after excersise.

5. Compare results for each group

• More haemoglobin

• more oxygen is able to be transported per cm³

• Cells can respire more for energy.

which two blood vessels carry deoxygenated blood?

• Pulmonary artery

• Vena Cava

where are pace makers fitted?

On the right atrium.

What condition may be treated with an artificial pacemaker?

Irregular heart beats

Eggs were placed into a beaker with water.

Explain why the masses of the eggs increased.

• Water was able to move into the eggs by osmosis

• From a high concentration of water molecules to a more lower concentration of water in the egg.

EXTRA:

may 2018, biology higher tier paper 1H.

Q. 4.4

getting that last mark for why magnesium deficiencies cause stunted growth.

therefore the plants makes less glucose and less glucose is converted into protein for growth —> stunted growth.

How to test for different carbohydrates:

Testing for sugars:

• Benedict’s solution for sugars

• ass benedict’s solution to milk and boil at a temperature above 60 degrees celcius.

• Solution will turn brick red if sugars/ carbohydrates are present.

Explain why the indicator in both tubes became colourless.

• Lipase breaks down fat into fatty acids in both testubes.

• Fatty acids lower the pH

• Fatty acids cause the pH to be below 10.

Give one reason why the measurement of time taken for the indicator to become colourless might be inaccurate

Observations of colour change are subjective.

Explain the difference in results for the last two test tubes in Table 9.

• Bile emulsifies fats

• Creates larger surface area

• Therefore lipase can break down the fats more quickly.