Edexcel GCSE Biology Paper 1 Higher June 2018 question paper 1BI0/1H

Figure 1 shows an eye.

When the eye changes from focusing on a distant object to focusing on a near object

Give a reason why people who are short-sighted cannot see distant objects clearly.

State the type of lens that can be used to correct short-sightedness.

A student was given the hypothesis ‘People with brown eyes are more likely to be short-sighted than people with blue eyes.’

Devise a plan to test this hypothesis.

Obesity increases the risk of a person developing cardiovascular disease.

Losing weight can reduce the risk of this disease occurring.

Explain why exercise can cause weight loss.

Figure 2 shows a gastric band fitted to a stomach.

Explain how a gastric band helps a person to lose weight.

BMI and waist: hip ratio can be used to find out if a person is obese.

Figure 3 shows some data for two males.

BMI is calculated using the equation:

Male B has a mass of 72 kg and a height of 1.81 m.

Calculate the BMI of male B.

Give the answer to 3 significant figures.

Figure 4 shows the interpretation of BMI values.

Males with a waist: hip ratio above 0.90 are defined as abdominally obese.

Explain what the BMI and waist: hip ratio for male A shows about his weight distribution.

(a) Figure 5 shows two potato chips.

Figure 6 shows some information about each potato chip.

Calculate the total surface area of potato chip B using the formula,

Total surface area = 2XY + 2XZ + 2YZ

The potato chips were placed in distilled water for 20 minutes.

Figure 7 shows the increase in mass of each potato chip.

Explain why potato chip B has a greater increase in mass than potato chip A.

Potato chip A is transferred from the distilled water into a concentrated salt solution.

Explain what will happen to the cells in potato chip A.

The potatoes of a potato plant develop underground.

Explain one difference in the sub-cellular structures in a cell in the potato and those in a cell in the leaf of the potato plant.

(a) Figure 8 shows a method of producing plants.

Step 1. Cells taken from parent plant.

Step 2. Cells placed on agar growth medium.

Step 3. Cells develop into tiny plantlets.

Step 4. Plantlets grown in compost.

Figure 8

Some cells in each plantlet develop into root cells.

Name the process occurring as these cells develop into root cells.

Describe the advantages of producing plants by the method shown in Figure 8.

An autoclave is used to prepare the agar growth medium used in Step 2.

Explain why the agar growth medium is autoclaved.

One of the plantlets had different coloured leaves.

Give one reason why this plantlet had different coloured leaves.

Crop plants provide a source of energy in the form of carbohydrates such as starch and sugars.

Describe the test to identify starch.

The amount of energy in the sugars extracted from crop plants can be measured using the calorimeter shown in Figure 9.

Explain why the calorimeter has a lid.

State why it is important to stir the water in the calorimeter.

Streptococcus bacteria can cause a sore throat or skin infection.

An illness called scarlet fever can also develop during an infection with this bacterium.

Give two precautions a doctor should take when treating a patient who is infected with Streptococcus.

From September 2013 to March 2014 there were 2 830 cases of scarlet fever in the UK.

From September 2014 to March 2015 there were 5 943 cases of scarlet fever.

Calculate the percentage increase of the number of cases of scarlet fever between the periods September 2014 to March 2015 and September 2013 to March 2014.

Figure 10 shows some Streptococcus bacteria.

Some bacteria are motile, meaning they can move themselves.

Why is a Streptococcus bacterium not motile?

Patients with scarlet fever can be treated with antibiotics.

New antibiotics need to be tested before they can be used in patients.

Which is the correct sequence for the development of a new medicine?

volunteers
cultured cells
on patients

cultured cells
on patients
volunteers

volunteers
on patients
cultured cells

cultured cells
volunteers
on patients

Most cases of scarlet fever occur in children.

Adults have usually developed immunity to a toxin that the Streptococcus bacteria produce during infection.

Explain how an adult develops immunity to the toxin.

In 2012, two scientists were awarded the Nobel prize for their research on stem cells.

They showed that adult cells could be reprogrammed to become cells with the properties of embryonic stem cells.

Describe the possible benefits of this research.

Figure 11 shows four stages of mitosis, labelled P, Q, R and S.

Which is the correct order for these stages?

The stage of mitosis labelled S in figure 11 is

Interphase is part of the cell cycle.

Describe what happens during interphase.

Figure 12 shows a root tip with cells in different stages of mitosis.

The image was magnified 400 ×.

Explain how a magnification of 400 × can be obtained using the lenses on a light microscope.

(a) Figure 13 shows the pentadactyl limb of a bat and a cat.

Describe the reasons why the anatomy of the pentadactyl limb suggests that bats and cats evolved from a common ancestor.

Genetic analysis also provides evidence for evolution.

Scientists can sequence genes from different organisms.

Describe how this type of genetic analysis provides evidence for evolution.

Mendel’s research on pea plants showed that genetic traits are inherited.

Which term is used to describe the expression of traits in an organism?

Mendel crossed pea plants that produced round seeds with pea plants that produced wrinkled seeds.

All the offspring produced round seeds.

He then crossed these offspring with each other.

Some pea plants in the next generation produced round seeds and the others produced wrinkled seeds.

Explain how this showed that some inherited traits are not expressed in an organism.

Duchenne muscular dystrophy is a recessive sex-linked genetic disorder. This disorder causes muscle weakness.

Figure 14 shows the inheritance of Duchenne muscular dystrophy in a family.

State and explain the phenotype of person Z.

Potato cells contain the enzyme catalase.

This enzyme catalyses the breakdown of hydrogen peroxide into oxygen and water.

Figure 15 shows what happened when a student placed a potato disc in a 5% hydrogen peroxide solution.

hydrogen oxygen bubbles cause

solution

The student measured the time taken for the potato disc to rise.

The student repeated the investigation using 10%, 15% and 20% concentrations of hydrogen peroxide solution.

Which term describes the hydrogen peroxide in this reaction?

The potato discs all had the same mass.

Explain why the student used potato discs with the same mass.

State two other factors that need to be kept the same to improve this investigation.

Figure 16 shows the results of this investigation.

The student calculated the rate of reaction using

State and explain a conclusion based on these results.

The student repeated the investigation with a 25% hydrogen peroxide solution and recorded a time of 75 seconds.

Calculate the rate of reaction for the 25% hydrogen peroxide solution.

The student decided that the rate for the 25% hydrogen peroxide solution was not anomalous.

Give the reason why the result was not anomalous.

(a) Yeast cells can be genetically modified to produce a painkiller.

This painkiller is usually obtained from opium poppies.

One method for genetically modifying a yeast cell uses a plasmid containing the desired gene.

Explain how a gene can be inserted into a plasmid.

Discuss the possible benefits and risks of producing painkillers from genetically modified yeast cells rather than extracting the painkillers from poppies.

Figure 17 shows the structure of a DNA nucleotide.

Structure A is a

*(ii) In 2003, the first complete human genome was sequenced.

The genomes of different people have small changes in the sequence of the DNA bases.

Describe how these changes in DNA sequence can affect the individuals and how sequencing a person’s genome could influence their medical treatments.

A scientist was planning to compare the effectiveness of the antibiotic myxopyronin on two different species of bacteria.

Figure 18 shows the equipment the scientist can use.

agar plates
two species filter discs of
spreader
incubator of bacteria myxopyronin

Figure 18

Describe how the scientist could determine the effectiveness of myxopyronin on the two species of bacteria.

Myxopyronin inhibits bacterial RNA polymerase.

Explain why the antibiotic myxopyronin can be used to treat bacterial infections in humans.

*(b) Infections can also be caused by viruses.

Describe the lytic pathway of a virus and how this causes the spread of infection through a population.

Every effort has been made to contact copyright holders to obtain their permission for the use of copyright material. Pearson Education Ltd. will, if notified, be happy to rectify any errors or omissions and include any such rectifications in future editions.