Aqa Biology h

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GCSE BITESIZE Examinations

General Certi ficate of Secondary Education

AQA SCIENCE A BLY1A

Unit Biology B1a (Human Biology)

AQA BIOLOGY

Unit Biology B1a (Human Biology)

HIGHER TIER

Specimen Paper

Time allowed: 30 minutes

Maximum marks: 36

Instructions Answerall 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.


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HIGHER TIER

SECTION ONE

Questions ONE to FIVE

In these questions, match the lettersA, 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 drugsA, 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 oftenprescribed 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 damagethe liver and brain is 3.

Another harmful drug that has been linked to mental illness, and can lead topeople using harder drugs, is 4.

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_________________________________________________________________QUESTION TWO

Diseases related to diet are on the increase in the Western world.

Match diseasesA, B, C and D with the numbers 1-4 in the table.

A Heart disease

B Diabetes

C Arthritis

D High blood pressure

Descript ion of the disease

1 Disease in which joints between bones weardown

2 Disease which is related to obesity and highsalt intake

3 Disease caused by too much cholesterol in theblood

4 Disease in which the body becomes unable tocontrol the blood sugar level

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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 effectiveat 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 thebacteria grew. The white areas represent areas where the bacteria did not grow.

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3A 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

3B 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.

3C Using the information in the diagram, which antibiotic was most effective atkilling the bacteria?

1 tetracycline

2 ampicillin

3 penicillin

4 streptomycin

3D Strains of the bacterium Staphylococcus aureus have developed which areresistant to several types of antibiotic. Scientists have named these strainsMRSA.

These strains have developed as a result of...

1 natural selection.

2 selective breeding.

3 natural immunity.

4 dirty conditions in hospitals.


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QUESTION FOUR

Any new medical drug or procedure has to undergo extensive clinical trials. Thediagram 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.

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The drug varenicline has been developed to assist smokers in giving up. Followingsafety testing, it was clinically trialled to compare how well it worked againstanother anti-smoking drug called bupropion, and a placebo (sugar pill).

Scientists recorded the percentage of volunteers who stopped smoking over threetime intervals (12 weeks, 24 weeks and 52 weeks).

The results are shown in the table below:

Percentage in each group that had stoppedsmoking

Tablettaken

Number ofpeoplegiventablet Af ter 12

weeksAf ter 24 weeks Af ter 52 weeks

varenicline 352 44 29 22

bupropion 329 29 21 17

placebo 344 18 11 8

4B Using the information in the diagram and the table to assist you, at whichstage 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

4C 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 vareniclinecould 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 wereprepared by a different group of scientists.

This was done because

1 the scientists taking the results did not have the expertise to preparethe tablets.

2 it prevented the scientists who took the samples from influencing theresults.

3 it eliminated systematic error in collecting the results.

4 it spread the workload for the scientists involved in the drug trial.

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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 thesehormones is produced?

Site at which FSH isproduced

Site at whichoestrogen is

produced

Site at which LH isproduced

1

Pituitary gland Ovaries Pituitary gland

2Pituitary gland Pituitary gland Ovaries

3Womb Ovaries Pituitary gland

4Pituitary gland Ovaries Ovaries

5B 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

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Knowledge of the hormones which regulate the menstrual cycle can be used byscientists to increase or reduce a womans fertility.

5C One type of female contraceptive pill contains the hormone oestrogen. Whywould 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 fertilisingthe egg.

5D In vitro fertilisation (IVF) has helped many infertile couples to have children.In this technique, scientists inject hormones to allow them to harvestseveral of the womans eggs, which they fertilise in a lab using sperm fromthe man.

However,some people object to the ethics of using IVF to assist infertilecouples.

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 humanpopulation.

4 IVF costs the NHS large amounts of money.

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QUESTION SIX

The diagram below shows the parts of the nervous system involved in a reflexaction:

6A Which part of this diagram represents a synapse?

1 A

2 C

3 D

4 F

6B Which row in the table below shows the correct position of the neuronesinvolved in a reflex action?

Relay neurone Sensoryneurone Motor neurone

1 C B E

2 B E C

3 B C E

4 E B C


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QUESTION SEVEN

During the first half of the 20th century, death rates from lung cancer showed anincrease 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 roadtarmac 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 cancerand found that the common factor linking them was smoking. This led them tocarry 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 diedfrom lung cancer.

When analysing their results, they represented the general lung cancer death rateamong men as 100%, and represented the death rates from lung cancer amongdifferent groups of smokers/non-smokers as percentage comparisons to this 100%figure. Their results are shown in the table below:

Amount of tobacco smoked perday in g

Percentage death rate from lungcancer compared with the generalpercentage 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 What is the increase in risk of dying from lung cancer for males who smokeheavily, compared with non-smokers?

1 Approximately twice as great

2 Approximately ten times greater

3 Approximately 20 times greater

4 Approximately 195 times greater

7C 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.

7D After his work was published, Sir Richard Doll worked for many cancerresearch organisations. During this time, he was also paid as a consultantby 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 thedata.

2 he was an eminent scientist in his field, whose views were valued byother scientists.

3 they could manipulate him into passing chemicals which wereunsafe.

4 he was well liked by the public, and this was good publicity for theirproducts.

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QUESTION EIGHT

Vaccination involves exposing the white blood cells to an inactive or deadmicroorganism. 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 thevaccine.

Why would only vaccinating 95 per cent of people be enough to protect thewhole population from a disease?

1 The antibodies made by the people who were vaccinated could bepassed 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 andspread.

The graph below shows the number of cases of measles in England and Walesbetween 1940 and 2004, and the percentage of children who were vaccinatedagainst measles after 1968.


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8B What was the range in measles cases seen in the years before the firstmeasles vaccination was introduced?

1 147,000 to 764,000

2 147 to 764

3 1940 to 1967

4 180,000 to 694,000

8C In 1998, a team of scientists led by Dr Andrew Wakefield published anarticle claiming that their data indicated a potential link between the

combined measles, mumps and rubella (MMR) vaccine and a conditionknown as autism. This led to some parents not vaccinating their children.

Between 1998 and 2001, by how much did the percentage of children thatwere vaccinated decrease?

1 0.5 per cent

2 7 per cent

3 60 per cent

4 80 per cent

8D Flu vaccines, containing inactivated influenza virus, are available. However,they have not been as successful as vaccines such as the MMR vaccine atconferring long-term immunity to the disease.

The reason why flu vaccination is not as effective at conferring long-termimmunity is

1 The inactivated flu virus in the vaccine is not detected by white bloodcells.

2 The viruses in the vaccine do not work because they have beeninactivated.

3 The vaccine needs further development.

4 The influenza virus mutates frequently to produce new strains.


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QUESTION NINE

This question is about cholesterol.

9A Read the statements below:

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)

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.

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In an investigation, 60 people had their normal diet replaced with a controlled dietthat was high in foods containing either saturated, monounsaturated orpolyunsaturated fats.

The total LDL cholesterol and HDL cholesterol levels in the blood were takenbefore 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 thenmeasured.

The graph below shows the results of this investigation:

9B How much higher were HDL cholesterol levels for the diet containingsaturated fats, compared with the diet containing monounsaturated fats?

1 2 per cent

2 10 per cent

3 12 per cent

4 25 per cent

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9C Which of these statements is a valid conclusion to draw from theinvestigation?

1 A diet that is high in saturated fats is best, as it increases the level ofHDL cholesterol the most.

2 A diet that is high in polyunsaturated fats is best, as it lowers LDLcholesterol the most.

3 A diet that is high in saturated fats is best, as it increases the level ofLDL cholesterol.

4 A diet that is high in monounsaturated fats is best, as it gives the bestcombination in terms of reducing LDL cholesterol while increasingHDL cholesterol.

9D In the experiment, some of the 60 people tested showed changes in theirLDL and HDL cholesterol levels above or below the mean changes shownin 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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Aqa Biology h