GCSE BITESIZE Examinations
General Certificate of Secondary Education
AQA SCIENCE A
Unit Biology B1a
BLY1A
(Human Biology)
AQA BIOLOGY
Unit Biology B1a
(Human Biology)
HIGHER TIER
Specimen Paper
Time allowed: 30 minutes
Maximum marks: 36
Instructions
• Answer all of the questions for the Tier you are attempting.
• Record your answers on a separate answer sheet only.
• Do all rough work in this book - not on your answer sheet.
Advice
• Do not choose more responses than you are asked to. You will lose marks if you
do.
1
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HIGHER TIER
SECTION ONE
Questions ONE to FIVE
In these questions, match the letters A, B, C and D with the numbers 1-4.
Use each answer only once.
Mark your choice on the answer sheet.
QUESTION ONE
This question is about drugs.
Match drugs A, B, C and D with the numbers 1-4 in the sentences.
A
alcohol
B
cannabis
C
painkillers
D
statins
Drugs are chemicals which alter the way the body works.
Some drugs are used medically. Patients with high cholesterol levels are often
prescribed …1….
Patients with a bacterial or viral infection often take …2… to relieve the symptoms.
However, some drugs are harmful. One widely consumed drug that can damage
the liver and brain is …3….
Another harmful drug that has been linked to mental illness, and can lead to
people using harder drugs, is …4….
Turn over ►
2
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QUESTION TWO
Diseases related to diet are on the increase in the Western world.
Match diseases A, B, C and D with the numbers 1-4 in the table.
A
Heart disease
B
Diabetes
C
Arthritis
D
High blood pressure
Description of the disease
1
Disease in which joints between bones wear
down
2
Disease which is related to obesity and high
salt intake
3
Disease caused by too much cholesterol in the
blood
4
Disease in which the body becomes unable to
control the blood sugar level
Turn over ►
3
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SECTION TWO
Questions THREE to NINE
Each of these questions has four parts.
In each part, choose only one answer.
Mark your choices on the answer sheet.
QUESTION THREE
An investigation was carried out to determine which antibiotic was most effective
at killing a species of bacteria. The bacteria were spread onto an agar plate. Then
four discs soaked with different antibiotics were placed on the surface of the agar.
The plates were incubated for 48 hours to allow the bacteria to reproduce.
The diagram below shows the results. The grey areas represent areas where the
bacteria grew. The white areas represent areas where the bacteria did not grow.
Turn over ►
4
3A
3B
3C
3D
The independent variable in this investigation was the type of antibiotic.
What kind of variable is this?
1
Continuous variable
2
Discrete variable
3
Ordered variable
4
Categoric variable
The results from this investigation would be best displayed using...
1
a scattergram.
2
a line graph.
3
a bar chart.
4
a pie chart.
Using the information in the diagram, which antibiotic was most effective at
killing the bacteria?
1
tetracycline
2
ampicillin
3
penicillin
4
streptomycin
Strains of the bacterium Staphylococcus aureus have developed which are
resistant to several types of antibiotic. Scientists have named these strains
MRSA.
These strains have developed as a result of...
1
natural selection.
2
selective breeding.
3
natural immunity.
4
dirty conditions in hospitals.
5
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QUESTION FOUR
Any new medical drug or procedure has to undergo extensive clinical trials. The
diagram below shows the stages involved in drug testing in the UK:
4A
During human testing, why is the drug tested on healthy volunteers first?
1
To test how good the drug is at curing people.
2
To test the safety of the drug.
3
To test the long-term effects of the drug.
4
To compare the drug against other drugs on the market.
Turn over ►
6
The drug varenicline has been developed to assist smokers in giving up. Following
safety testing, it was clinically trialled to compare how well it worked against
another anti-smoking drug called bupropion, and a placebo (sugar pill).
Scientists recorded the percentage of volunteers who stopped smoking over three
time intervals (12 weeks, 24 weeks and 52 weeks).
The results are shown in the table below:
Tablet
taken
4B
4C
Number of
people
given
tablet
Percentage in each group that had stopped
smoking…
After 12
weeks
After 24 weeks
After 52 weeks
varenicline
352
44
29
22
bupropion
329
29
21
17
placebo
344
18
11
8
Using the information in the diagram and the table to assist you, at which
stage of the drug-testing procedure is this study likely to have taken place?
1
Laboratory stage
2
Phase 1
3
Phase 3
4
Phase 4
Why did the scientists give some of the volunteers a placebo (sugar pill)?
1
To show that the patients could not give up on their own.
2
To see the effects that sugar had on the obesity of the volunteers.
3
To make varenicline appear more effective than it is.
4
To act as a control group which the effectiveness of the varenicline
could be compared against.
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4D
The scientists who collected the results deliberately did not know whether
the patient was taking the drug or the placebo tablet, as the tablets were
prepared by a different group of scientists.
This was done because…
1
the scientists taking the results did not have the expertise to prepare
the tablets.
2
it prevented the scientists who took the samples from influencing the
results.
3
it eliminated systematic error in collecting the results.
4
it spread the workload for the scientists involved in the drug trial.
Turn over ►
8
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QUESTION FIVE
This question is about the menstrual cycle.
5A
The menstrual cycle is regulated by hormones.
Which row of the table shows the correct site where each of these
hormones is produced?
Site at which LH is
produced
Pituitary gland
Site at which
oestrogen is
produced
Ovaries
Pituitary gland
Pituitary gland
Ovaries
Womb
Ovaries
Pituitary gland
Pituitary gland
Ovaries
Ovaries
Site at which FSH is
produced
1
2
3
4
5B
Pituitary gland
What is the role of the hormone FSH?
1
Causes the womb lining to become thicker
2
Stops the production of LH
3
Causes an egg to mature in an ovary
4
Causes the release of an egg from an ovary
Turn over ►
9
Knowledge of the hormones which regulate the menstrual cycle can be used by
scientists to increase or reduce a woman’s fertility.
5C
5D
One type of female contraceptive pill contains the hormone oestrogen. Why
would taking oestrogen on a daily basis prevent pregnancy?
1
It would prevent the woman from having a period.
2
It would inhibit any eggs from maturing.
3
It would prevent the release of eggs from the ovaries.
4
It would kill sperm cells, thereby preventing the sperm from fertilising
the egg.
In vitro fertilisation (IVF) has helped many infertile couples to have children.
In this technique, scientists inject hormones to allow them to harvest
several of the woman’s eggs, which they fertilise in a lab using sperm from
the man.
However, some people object to the ethics of using IVF to assist infertile
couples.
Which of these is a valid ethical objection?
1
The baby is often born with abnormalities.
2
Spare embryos are often frozen, and may eventually be disposed of.
3
The use of this technology is causing rapid growth in the human
population.
4
IVF costs the NHS large amounts of money.
Turn over ►
10
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QUESTION SIX
The diagram below shows the parts of the nervous system involved in a reflex
action:
6A
6B
Which part of this diagram represents a synapse?
1
A
2
C
3
D
4
F
Which row in the table below shows the correct position of the neurones
involved in a reflex action?
Relay neurone
Sensory
neurone
Motor neurone
1
C
B
E
2
B
E
C
3
B
C
E
4
E
B
C
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6C
If a person touches a hot object, the reflex response is for their arm to move
away from it. The pathway of neurones which link the receptors and the arm
muscle is approximately 1.6 metres long. Assuming that a nerve impulse
travelled at 100 metres per second, it should take 0.016 seconds for an
impulse to travel this distance.
In reality, the reflex action can take up to 0.5 seconds to produce a
response. Which of these statements is not a plausible explanation for this?
6D
1
The brain needs time to coordinate an appropriate response.
2
It takes time for the synapse to produce chemicals.
3
Transmission across the synapses is slower than along the
neurones.
4
It takes time for the muscle to contract in response to an electrical
impulse.
In addition to the nervous system, hormones are also used to coordinate
processes within the body.
Hormones are released by…
1
receptors.
2
organs.
3
the blood.
4
glands.
Turn over ►
12
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QUESTION SEVEN
During the first half of the 20th century, death rates from lung cancer showed an
increase year upon year. In 1950, this prompted two British scientists, Sir Richard
Doll and Sir Austin Bradford Hill, to investigate the cause of this increase.
7A
At first they thought carcinogenic chemicals from motor car fumes and road
tarmac were responsible for the increase.
This was…
1
an observation.
2
a hypothesis.
3
a theory.
4
a conclusion.
They initially surveyed 700 hospital patients who were suffering from lung cancer
and found that the common factor linking them was smoking. This led them to
carry out a much more extensive study of 40,000 doctors over a four-year period,
collecting information on how many of them smoked, and how many of them died
from lung cancer.
When analysing their results, they represented the general lung cancer death rate
among men as 100%, and represented the death rates from lung cancer among
different groups of smokers/non-smokers as percentage comparisons to this 100%
figure. Their results are shown in the table below:
Amount of tobacco smoked per
day in g
Percentage death rate from lung
cancer compared with the general
percentage death rate from lung
cancer among all males
0 (Non-smokers)
9%
1-14 (Light smokers)
58%
15-24 (Moderate smokers)
106%
25 or more (Heavy smokers)
205%
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7B
7C
7D
What is the increase in risk of dying from lung cancer for males who smoke
heavily, compared with non-smokers?
1
Approximately twice as great
2
Approximately ten times greater
3
Approximately 20 times greater
4
Approximately 195 times greater
Why did they carry out such a large study of 40,000 doctors?
1
To make their data more accurate.
2
To make their data more precise.
3
To make their data more reliable.
4
To make their data more sensitive.
After his work was published, Sir Richard Doll worked for many cancer
research organisations. During this time, he was also paid as a consultant
by many chemical companies to advise them on chemicals and analyse
data to see whether their chemicals were linked to cancers.
These companies are likely to have sought his help because…
1
his background made him the only scientist qualified to analyse the
data.
2
he was an eminent scientist in his field, whose views were valued by
other scientists.
3
they could manipulate him into passing chemicals which were
unsafe.
4
he was well liked by the public, and this was good publicity for their
products.
Turn over ►
14
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QUESTION EIGHT
Vaccination involves exposing the white blood cells to an inactive or dead
microorganism. The white cells then respond rapidly to any future re-infection by
that microorganism.
8A
For a vaccine to be effective in protecting a population from the disease,
scientists state that 95 per cent of the population needs to receive the
vaccine.
Why would only vaccinating 95 per cent of people be enough to protect the
whole population from a disease?
1
The antibodies made by the people who were vaccinated could be
passed on to the remaining 5 per cent.
2
There would be insufficient susceptible people to spread the disease.
3
Medicines could be focused on treating the remaining 5 per cent.
4
The vaccine would eventually be passed to the next generation and
spread.
The graph below shows the number of cases of measles in England and Wales
between 1940 and 2004, and the percentage of children who were vaccinated
against measles after 1968.
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8B
8C
What was the range in measles cases seen in the years before the first
measles vaccination was introduced?
1
147,000 to 764,000
2
147 to 764
3
1940 to 1967
4
180,000 to 694,000
In 1998, a team of scientists led by Dr Andrew Wakefield published an
article claiming that their data indicated a potential link between the
combined measles, mumps and rubella (MMR) vaccine and a condition
known as autism. This led to some parents not vaccinating their children.
Between 1998 and 2001, by how much did the percentage of children that
were vaccinated decrease?
8D
1
0.5 per cent
2
7 per cent
3
60 per cent
4
80 per cent
Flu vaccines, containing inactivated influenza virus, are available. However,
they have not been as successful as vaccines such as the MMR vaccine at
conferring long-term immunity to the disease.
The reason why flu vaccination is not as effective at conferring long-term
immunity is…
1
The inactivated flu virus in the vaccine is not detected by white blood
cells.
2
The viruses in the vaccine do not work because they have been
inactivated.
3
The vaccine needs further development.
4
The influenza virus mutates frequently to produce new strains.
16
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QUESTION NINE
This question is about cholesterol.
9A
Read the statements below:
i) The amount of cholesterol in the blood depends on your diet only.
ii) High-density lipoproteins (HDLs) are considered to be ‘good cholesterol’.
iii) Excessive cholesterol in the blood can contribute to narrowing of the
blood vessels.
Which of the statements in the box above are correct?
1.
i) and ii)
2.
i) and iii)
3.
ii) and iii)
4.
i), ii) and iii)
Turn over ►
17
In an investigation, 60 people had their normal diet replaced with a controlled diet
that was high in foods containing either saturated, monounsaturated or
polyunsaturated fats.
The total LDL cholesterol and HDL cholesterol levels in the blood were taken
before the start of the investigation, and after several weeks on the replacement
diet. The change in LDL and HDL cholesterol levels in the blood was then
measured.
The graph below shows the results of this investigation:
9B
How much higher were HDL cholesterol levels for the diet containing
saturated fats, compared with the diet containing monounsaturated fats?
1
2 per cent
2
10 per cent
3
12 per cent
4
25 per cent
Turn over ►
18
9C
Which of these statements is a valid conclusion to draw from the
investigation?
9D
1
A diet that is high in saturated fats is best, as it increases the level of
HDL cholesterol the most.
2
A diet that is high in polyunsaturated fats is best, as it lowers LDL
cholesterol the most.
3
A diet that is high in saturated fats is best, as it increases the level of
LDL cholesterol.
4
A diet that is high in monounsaturated fats is best, as it gives the best
combination in terms of reducing LDL cholesterol while increasing
HDL cholesterol.
In the experiment, some of the 60 people tested showed changes in their
LDL and HDL cholesterol levels above or below the mean changes shown
in the graph.
Theses differences are likely to be due to…
1
systematic error in how the scientists carried out the technique.
2
variation in the diet of the 60 volunteers.
3
the measuring equipment being incorrectly calibrated.
4
variation in inherited factors among the 60 volunteers.
END OF QUESTIONS
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