Inheritance: OCR GCSE Biology A questions

Every OCR GCSE Biology A exam question on B5.1 Inheritance, 2018–2025, with its mark scheme and examiner’s report.

All 139 questions on Inheritance, as a list

June 2025, Paper 2 Foundation, Q5 (1 mark): Who developed a theory about how characteristics are inherited in pea plants? A Darwin B Darwin and Wallace C Mendel D Mendel and Wallace Your answer [1]
June 2025, Paper 2 Foundation, Q8 (1 mark): A horse has 64 chromosomes in a muscle cell. How many chromosomes are in a horse sperm cell? A 16 B 32 C 64 D 128 Your answer [1]
June 2025, Paper 2 Foundation, Q10 (1 mark): Which description is correct for human egg cells? A They contain an X and a Y chromosome. B They contain one X chromosome. C They contain one Y chromosome. D Th
June 2025, Paper 2 Foundation, Q11 (1 mark): Greenfly are small insects that can reproduce sexually or asexually. A population of greenfly live in a constant environment and are well adapted. Which stateme
June 2025, Paper 2 Foundation, Q13 (1 mark): Cystic fibrosis is a genetic disorder. It is caused by a recessive allele f. A female who has the genotype Ff is expecting a baby. The father has the genotype F
June 2025, Paper 2 Foundation, Q17(a) (3 marks): Complete the sentences about the family tree. Use words from the list. dominant female with SIOD heterozygous homozygous male with SIOD recessive The phenotype
June 2025, Paper 4 Higher, Q5 (1 mark): An organism has the alleles Aa for a gene. What do the Aa alleles represent? A A heterozygous genotype B A heterozygous phenotype C A homozygous genotype D A ho
June 2025, Paper 4 Higher, Q6 (1 mark): Which of these units of genetic material is largest? A Base B Chromosome C Gene D Genome Your answer [1]
June 2025, Paper 4 Higher, Q7 (1 mark): The flow chart shows some developments in our understanding of genetics. A The characteristics of two parents are blended so that the offspring has intermediate
June 2025, Paper 4 Higher, Q9 (1 mark): A muscle cell in a horse has 64 chromosomes. Which of these statements is correct? A A horse egg cell has 64 chromosomes and is haploid. B A horse liver cell ha
June 2025, Paper 4 Higher, Q11 (1 mark): Which description is correct for human sperm cells? A They always contain an X chromosome. B They always contain a Y chromosome. C They contain an X and a Y chr
June 2025, Paper 4 Higher, Q15 (1 mark): How may a mutation in non-coding DNA result in a change in phenotype? A It changes the amino acid sequence of a protein. B It changes the shape of the active si
June 2025, Paper 4 Higher, Q19(a) (2 marks): SIOD is caused by a recessive allele. Explain how you can tell from the family tree that the allele for SIOD is recessive. [2]
June 2025, Paper 4 Higher, Q19(b) (3 marks): The parents A and B are expecting another child. Predict the probability that this child will have SIOD. Complete the genetic diagram to explain your answer usi
June 2025, Paper 4 Higher, Q21(a) (1 mark): Which type of test, A, B, C, D or E, is identifying risk factors? [1]
June 2025, Paper 4 Higher, Q21(b) (1 mark): Which type of test, A, B, C, D or E, will not affect the person being tested but might be useful if they are planning to have children? [1]
June 2025, Paper 4 Higher, Q21(d) (1 mark): Deciding whether to take test C can be a difficult decision for some people. Suggest one possible reason why. [1]
June 2024, Paper 2 Foundation, Q4 (1 mark): Many plants can reproduce either asexually or sexually. What is a feature of sexual reproduction? A All the offspring are better adapted to the environment. B M
June 2024, Paper 2 Foundation, Q6 (1 mark): Cystic fibrosis is caused by a recessive allele (f). The diagram shows a genetic cross. Parent 1 F f f Ff ff Parent 2 f Ff ff Which percentage of the offspring
June 2024, Paper 2 Foundation, Q10 (1 mark): Which sex chromosomes are found in human egg cells? A All egg cells have one X chromosome. B All egg cells have one Y chromosome. C All egg cells have two X chr
June 2024, Paper 2 Foundation, Q12 (1 mark): Mendel discovered some of the principles of genetics. He crossed tall pea plants with short pea plants. All the offspring were tall. How did Mendel explain this
June 2024, Paper 2 Foundation, Q15 (1 mark): Which process can make new alleles? A Evolution B Mutation C Selective breeding D Specialisation Your answer [1] Section B
June 2024, Paper 2 Foundation, Q18(b)(ii) (1 mark): The fungus reproduces using spores. Which type of reproduction uses meiosis to make spores? [1]
June 2024, Paper 2 Foundation, Q19(a) (2 marks): 700 000 babies are born each year in the UK. 35 of these babies are born with SMA. Calculate the percentage of babies that have SMA. Percentage of babies with S
June 2024, Paper 2 Foundation, Q19(b)(i) (1 mark): Use the key to give the phenotype of person A. [1]
June 2024, Paper 2 Foundation, Q19(b)(ii) (1 mark): Which term describes the genotype of person B? Tick (3) one box. Heterozygous Homozygous dominant Homozygous recessive [1]
June 2024, Paper 2 Foundation, Q19(b)(iii) (3 marks): People that have SMA cannot produce a protein that is needed for their motor neurones to function. Explain why person C has difficulty moving their legs. [3]
June 2024, Paper 2 Foundation, Q19(c)(i) (1 mark): Why is the gene inserted into the nucleus of the motor neurone? [1]
June 2024, Paper 4 Higher, Q2 (1 mark): Which process can make new alleles? A Evolution B Mutation C Selective breeding D Specialisation Your answer [1]
June 2024, Paper 4 Higher, Q6 (1 mark): The graph shows the changes in chromosome number in a cell during meiosis. 8 6 Chromosome number 4 2 Time What is the diploid number of chromosomes for this cel
June 2024, Paper 4 Higher, Q7 (1 mark): A gene controlling a characteristic has two possible alleles, A and a. A is the dominant allele. One person is Aa and another person is AA for this gene. Which
June 2024, Paper 4 Higher, Q9 (1 mark): The diagram shows the results of two different crosses of rats. Female Male Female x x 1 2 3 Which is a possible explanation of the results of these crosses? A
June 2024, Paper 4 Higher, Q22(a) (2 marks): There are 66 million people in the UK. Calculate the number of cases of Huntington’s disease in the UK. Number of cases = [2]
June 2024, Paper 4 Higher, Q22(b) (3 marks): All three diseases affect proteins in different parts of the body. Explain why each of these diseases cause difficulty in moving the legs. Huntington’s MD SMA [
June 2024, Paper 4 Higher, Q22(c) (2 marks): Suggest why the mutation that causes Huntington’s is dominant but the mutation that causes MD and SMA is recessive. Use the information in the effect column of
June 2023, Paper 2 Foundation, Q3 (1 mark): Using the data in the table, how many people living in the UK have a Y chromosome in their cells? Number of individuals of each sex in the UK, rounded to 2 sign
June 2023, Paper 2 Foundation, Q4 (1 mark): A genetic disorder is caused by a dominant allele (D). The recessive allele is (d). Which row shows all the possible genotypes for heterozygous and homozygous i
June 2023, Paper 2 Foundation, Q5 (1 mark): Which sentence is a correct description of a chromosome? A A length of protein that contains the genetic material. B A long molecule of DNA that contains genes.
June 2023, Paper 2 Foundation, Q7 (1 mark): There are 28 chromosomes in each elephant sperm cell. What is the diploid number of chromosomes in elephants? A 14 B 28 C 56 D 112 Your answer [1]
June 2023, Paper 2 Foundation, Q8 (1 mark): Charles Darwin and Gregor Mendel did important work in the development of science. Which row gives the areas of their work? Charles Darwin Gregor Mendel evoluti
June 2023, Paper 2 Foundation, Q16(c) (2 marks): Sorghum produces a bitter chemical in its seeds. This makes the seeds less likely to be eaten by birds. Complete each sentence about how the bitter chemical was
June 2023, Paper 2 Foundation, Q20(a) (1 mark): In the box next to each statement, put A if it applies to asexual reproduction or S if it applies to sexual reproduction. It is a quicker process. It introduces
June 2023, Paper 2 Foundation, Q23(a) (2 marks): A doctor makes this statement: The allele causing Gillespie syndrome in this family is recessive. Explain why this statement is correct. Use evidence from Fig.
June 2023, Paper 2 Foundation, Q23(b) (3 marks): Person A and person B are expecting another baby. Complete Fig. 23.2 to find the probability that it will have Gillespie syndrome. (Use G for the dominant allel
June 2023, Paper 4 Higher, Q4 (1 mark): What is the definition of the genome? A All the alleles that are expressed in the phenotype of an individual. B All the coding DNA that is present in an individ
June 2023, Paper 4 Higher, Q5 (1 mark): Which sentence describes Gregor Mendel’s discovery that helped develop our understanding of genetics? A Characteristics are controlled by DNA found in the nucle
June 2023, Paper 4 Higher, Q8 (1 mark): Which statement about genes and alleles is correct? A Mutations can produce new genes but not new alleles. B Only genes but not alleles can be dominant or reces
June 2023, Paper 4 Higher, Q11 (1 mark): In 2022, there were 66 900 000 people living in the UK. Estimate how many of these people have a Y chromosome in their cells. Individuals of each sex in the UK
June 2023, Paper 4 Higher, Q12 (1 mark): Which of these treatments is not an example of genomic medicine? A Advising people who have certain alleles to make changes in their lifestyle B Designing drugs
June 2023, Paper 4 Higher, Q15 (1 mark): Human fetuses have a different form of haemoglobin to adults. When a baby is born, a gene called BCL11A produces a protein that switches off the production of f
June 2023, Paper 4 Higher, Q17(a) (2 marks): A doctor makes this statement: The allele causing Gillespie syndrome in this family is recessive. Explain why this statement is correct. Use evidence from Fig.
June 2023, Paper 4 Higher, Q17(b) (3 marks): Person A and person B are expecting another baby. Complete Fig. 17.2 to find the probability that it will have Gillespie syndrome. (Use G for the dominant allel
June 2023, Paper 4 Higher, Q20(d)(ii) (2 marks): producing hybrid buddleia bushes that have uneven numbers of chromosomes, which prevent meiosis occurring [2]
June 2023, Paper 4 Higher, Q22(b)(i) (1 mark): What is the name given to this type of reproduction? [1]
June 2022, Paper 2 Foundation, Q2 (1 mark): Which of these factors affect the phenotype of an organism? A Only the environment of the organism. B Only the organism’s genes. C The organism’s genes and its
June 2022, Paper 2 Foundation, Q5 (1 mark): Which sperm would fertilise an egg to produce a female baby? A A sperm with one X chromosome. B A sperm with one Y chromosome. C A sperm with two X chromosomes.
June 2022, Paper 2 Foundation, Q15 (1 mark): What is the definition of a genome? A All the genes present in a community of organisms. B All the genes present in a gamete. C The entire genetic material of a
June 2022, Paper 2 Foundation, Q18(a) (2 marks): Tulips can be grown from seeds produced from sexual reproduction. They can also be grown from bulbs that are produced by asexual reproduction. Which statements
June 2022, Paper 2 Foundation, Q18(b) (3 marks): In 1637, tulip growers found that a small number of their tulip plants produced flowers with different coloured stripes. The growers did not know what was causi
June 2022, Paper 2 Foundation, Q19(a)(i) (2 marks): Complete the table about the family tree. The first row has been done for you. Number in the family Number of males 6 Number of people who are homozygous recess
June 2022, Paper 2 Foundation, Q19(a)(ii) (2 marks): Person 1 and person 2 are expecting another baby. Complete the genetic diagram to find the probability that the baby will have amyloidosis. Person 1 Person 2 A
June 2022, Paper 2 Foundation, Q19(b) (3 marks): Amyloid protein is made by blood cells called plasma cells. Amyloid can stop the pancreas releasing insulin. It can also prevent sensory neurones from working.
June 2022, Paper 4 Higher, Q2 (1 mark): What is the definition of a genome? A All the genes present in a community of organisms. B All the genes present in a gamete. C The entire genetic material of a
June 2022, Paper 4 Higher, Q18(a) (2 marks): Tulips can be grown from seeds produced from sexual reproduction. They can also be grown from bulbs that are produced by asexual reproduction. Explain why most
June 2022, Paper 4 Higher, Q18(b) (2 marks): In 1637, tulip growers found that a small number of their tulip plants produced flowers with different coloured stripes. Until recently, there were two possible
June 2022, Paper 4 Higher, Q19(a)(i) (2 marks): Complete the table about the family tree. The first row has been done for you. Number of people in the family males 6 people who are homozygous recessive for th
June 2022, Paper 4 Higher, Q19(a)(ii) (3 marks): Person 1 and person 2 are expecting another baby. Complete the genetic diagram to find the probability that the baby will have amyloidosis. Person 1 Person 2 Pr
June 2022, Paper 4 Higher, Q22(a)(i) (2 marks): Explain the difference between haploid and diploid cells. [2]
June 2022, Paper 4 Higher, Q22(a)(ii) (2 marks): Explain how meiosis usually makes gametes that will produce children without these genetic disorders. [2]
June 2022, Paper 4 Higher, Q22(b) (2 marks): The diagram shows the chromosomes found in a cell of a child. 3 2 4 5 1 6 10 9 11 12 7 8 15 14 18 13 16 17 X 19 22 Y 21 20 Write down two conclusions that can b
June 2022, Paper 4 Higher, Q22(c)(i) (2 marks): Give two conclusions that can be made from this graph. 1 2 [2]
June 2022, Paper 4 Higher, Q22(c)(ii) (1 mark): In the ovary, meiosis starts before a woman is born and is not completed until just before ovulation. How does this information explain the trends shown in the
November 2021, Paper 2 Foundation, Q5 (1 mark): Which process can result in a new allele being formed? A Asexual reproduction B Fertilisation C Mutation D Natural selection Your answer [1]
November 2021, Paper 2 Foundation, Q9 (1 mark): A genetic condition is controlled by a dominant allele P. How is the genotype Pp described? A Haploid B Heterozygous C Homozygous dominant D Homozygous recessiv
November 2021, Paper 2 Foundation, Q11 (1 mark): The diploid number of chromosomes in sheep is 54. How many chromosomes would be found in a sperm cell from a sheep? A 23 B 27 C 54 D 108 Your answer [1]
November 2021, Paper 2 Foundation, Q18(c)(i) (3 marks): There are 30 000 000 females in the UK and 1 in 400 of them has a mutation in their BRCA gene. • 60% of women with this mutation could develop breast cancer. •
November 2021, Paper 2 Foundation, Q19(a)(i) (2 marks): D represents the dominant allele and d the recessive allele. Person A in the family tree must have the genotype Dd. Explain how you can tell this from the famil
November 2021, Paper 2 Foundation, Q19(a)(ii) (2 marks): Person A and person B are expecting another child. Complete the genetic diagram to calculate the probability that the child will develop CJD. Person B d d D Per
November 2021, Paper 2 Foundation, Q21(d) (1 mark): The scientists also observed that the factors that determine sex in skinks are different than in humans. Which factor determines sex in humans? Tick (3) one box
November 2021, Paper 2 Foundation, Q21(e)(i) (2 marks): The scientists had 300 normal sized eggs. Calculate how many male skinks hatched from these eggs. Number of male skinks = [2]
November 2021, Paper 2 Foundation, Q21(e)(ii) (1 mark): Describe the relationship between egg size and the sex of the skinks. [1]
November 2021, Paper 2 Foundation, Q21(e)(iii) (2 marks): The scientists found that smaller eggs have a higher concentration of testosterone. Explain how this can account for the results shown in the graph. [2]
November 2021, Paper 4 Higher, Q5 (1 mark): Which pair of genetic terms have the same meaning? A Base and nucleotide B Gene and allele C Gene and genome D Variant and allele [1] Your answer
November 2021, Paper 4 Higher, Q11 (1 mark): The diploid number of chromosomes in sheep is 54. Sex in sheep is determined in the same way as in humans. Which is a possible chromosome combination in a sperm
November 2021, Paper 4 Higher, Q13 (1 mark): The pea plants studied by Mendel were either tall or dwarf. Scientists think that he was lucky to have chosen this characteristic because many other characteris
November 2021, Paper 4 Higher, Q15 (1 mark): Scientists have found that only about 1% of our DNA codes for proteins. The other 99% of DNA used to be called ‘junk’ DNA. Why is the term ‘junk’ DNA not used a
November 2021, Paper 4 Higher, Q21(a)(i) (2 marks): Complete this table about the family tree. 3 Number of people who will develop CJD Number of people that are homozygous recessive for this gene Number of people
November 2021, Paper 4 Higher, Q21(a)(ii) (2 marks): Person A and person B are expecting another child. Complete the genetic diagram to calculate the probability that the child will develop CJD. (Use D to represen
November 2020, Paper 2 Foundation, Q3 (1 mark): The table shows features of meiosis. Type of cells made Genetic variation introduced A body cells 3 B body cells ✗ C gametes 3 D gametes ✗ Which row in the tabl
November 2020, Paper 2 Foundation, Q9 (1 mark): Scientists found DNA from a Stone Age woman trapped in gum from a tree. The woman had chewed the tree gum. Using this DNA scientists were able to predict some o
November 2020, Paper 2 Foundation, Q10 (1 mark): The diagrams show gametes and sex chromosomes. Which diagram shows the correct combination of sperm and egg to produce a male baby? X Y Y X A B XY XX XY XY C D
November 2020, Paper 2 Foundation, Q11 (1 mark): Gregor Mendel studied the inheritance of characteristics in pea plants. Which of these is a possible reason why he chose pea plants for his experiments? A Pea p
November 2020, Paper 2 Foundation, Q12 (1 mark): Tigers have a diploid number of 38 chromosomes. How many chromosomes are present in a tiger sperm cell? A 2 B 19 C 38 D 72 Your answer [1]
November 2020, Paper 2 Foundation, Q21(a) (1 mark): Write the words allele, chromosome and nucleotide in the boxes to show their size from smallest feature to largest feature. Smallest feature Largest feature [1]
November 2020, Paper 2 Foundation, Q21(b) (1 mark): One in 500 people are heterozygous for HC. There are 66 000 000 people in the UK. Calculate how many people in the UK are heterozygous for HC. Number of people
November 2020, Paper 2 Foundation, Q21(c) (2 marks): A woman who does not have HC and a man who is heterozygous are expecting a baby. What is the probability of the baby having HC? Complete the genetic diagram to
November 2020, Paper 2 Foundation, Q21(d) (6 marks): Hypercholesterolemia (HC) is caused by a dominant allele on chromosome 19. This allele has mutations which cause a change in the order of DNA nucleotides. (d)*
November 2020, Paper 4 Higher, Q5 (1 mark): Why are the effects of most mutations not observed? A Most mutations do not affect the genotype or phenotype. B Most mutations do not affect the phenotype. C Mu
November 2020, Paper 4 Higher, Q7 (1 mark): The table describes meiosis. Genetic description of Genetic variation Type of cells made cells made introduced A haploid body cells 3 B diploid body cells ✗ C h
November 2020, Paper 4 Higher, Q11 (1 mark): Doctors are able to offer a diagnosis and treatment targeted to a patient’s genome, known as genomic medicine. Which is an example of the type of treatment used
November 2020, Paper 4 Higher, Q12 (1 mark): How can a mutation in non-coding DNA change the activity of a cell? A It can change the amino acid sequence in a protein. B The base sequence of mRNA may be alt
November 2020, Paper 4 Higher, Q21(a) (1 mark): Write the words allele, chromosome, genome and nucleotide in the boxes to show their size from smallest feature to largest feature. Smallest feature Largest fea
November 2020, Paper 4 Higher, Q21(b) (1 mark): One in 500 people are heterozygous for HC. There are 66 000 000 people in the UK. Calculate how many people in the UK are heterozygous for HC. Number of people
November 2020, Paper 4 Higher, Q21(c) (2 marks): A woman who does not have HC and a man who is heterozygous are expecting a baby. What is the probability of the baby having HC? Complete the genetic diagram to
November 2020, Paper 4 Higher, Q21(e) (6 marks): Hypercholesterolemia (HC) is the result of a mutation in the genome. It is caused by a dominant allele on chromosome 19. The mutation involved causes a change i
June 2019, Paper 2 Foundation, Q3 (1 mark): Which combination of gametes will produce a male baby? A A sperm with XY chromosomes and an egg with XX chromosomes. B A sperm with one X chromosome and an egg
June 2019, Paper 2 Foundation, Q7 (1 mark): Which of these is an example of discontinuous variation? A Body weight B Hand span C Height D Sex Your answer [1]
June 2019, Paper 2 Foundation, Q11 (1 mark): Cystic fibrosis is a genetic condition caused by a recessive allele (f). Which is the genotype of a person with cystic fibrosis? A Heterozygous and ff B Heteroz
June 2019, Paper 2 Foundation, Q12 (1 mark): Each cell in the eye of a kangaroo has 16 chromosomes. How many chromosomes are there in one kangaroo sperm cell? A 4 B 8 C 16 D 32 Your answer [1]
June 2019, Paper 2 Foundation, Q20(b) (3 marks): Some rats are resistant to warfarin. When fed with large amounts of warfarin the rats do not die. Scientists found that the resistance is due to the dominant al
June 2019, Paper 3 Higher, Q22(c)(i) (2 marks): DNA databases involve storing a person’s individual DNA profile. The DNA profile identifies DNA sequences present in an individual. DNA databases are used by ma
June 2019, Paper 3 Higher, Q22(c)(ii) (1 mark): Write down one reason why people might not want to be included on a DNA database. [1]
June 2019, Paper 4 Higher, Q3 (1 mark): What was Mendel’s contribution to modern genetics? A He developed the theory of natural selection. B He discovered that most characteristics are controlled by m
June 2019, Paper 4 Higher, Q21(a) (2 marks): Explain what is meant by the term dominant allele. [2]
June 2019, Paper 4 Higher, Q21(b) (6 marks): Huntington’s disease is a genetic condition. It is caused by a dominant allele. (b)* The symptoms of Huntington’s disease usually appear after the age of 40. Th
June 2019, Paper 4 Higher, Q23(b) (3 marks): In 1958, some rats were found that were resistant to warfarin. They did not die, even when fed with large amounts of the poison. Scientists found that the resis
June 2018, Paper 2 Foundation, Q3 (1 mark): There are two main types of reproduction, sexual and asexual. Which is an advantage of sexual reproduction? A Creates more variation B Produces larger numbers o
June 2018, Paper 2 Foundation, Q4 (1 mark): What did Gregor Mendel discover? A A theory for how life on Earth started B How characteristics are inherited in pea plants C The shape of the DNA molecule D Th
June 2018, Paper 2 Foundation, Q13 (1 mark): An organism has the genotype TT. Which term describes this organism? A Heterozygous dominant B Heterozygous recessive C Homozygous dominant D Homozygous recessi
June 2018, Paper 2 Foundation, Q14 (1 mark): Which process produces gametes? A Diffusion B Fertilisation C Meiosis D Mitosis [1] Your answer
June 2018, Paper 2 Foundation, Q16(a) (2 marks): Characteristics can be examples of continuous or discontinuous variation. Write the four characteristics below in the correct columns of the table. Sex Blood gr
June 2018, Paper 2 Foundation, Q16(b) (3 marks): Identical twins occur when an embryo splits into two. In the diagram below, some of the chromosome numbers in the different cells have been given to you. Egg ce
June 2018, Paper 2 Foundation, Q18(a) (2 marks): The sex chromosomes determine the sex of a baby. What are the sex chromosomes of a male and of a female? [2] Male Female
June 2018, Paper 2 Foundation, Q18(b)(i) (1 mark): What percentage of babies are male at birth? Answer = % [1]
June 2018, Paper 2 Foundation, Q18(b)(ii) (1 mark): In a hospital 410 babies are born in a week. Calculate how many of them are likely to be male. Answer = [1]
June 2018, Paper 2 Foundation, Q18(b)(iii) (2 marks): On average, men do not live as long as women. How does the data in the table show this? [2]
June 2018, Paper 2 Foundation, Q20(a) (2 marks): Explain the meaning of these terms. Mutation Gene [2]
June 2018, Paper 2 Foundation, Q20(b)(i) (1 mark): Why does a person need two affected alleles to have the condition? [1]
June 2018, Paper 2 Foundation, Q20(c) (3 marks): Two people are heterozygous for retinitis pigmentosa and are expecting a baby. Complete the genetic diagram to work out the probability that the baby will have
June 2018, Paper 4 Higher, Q4 (1 mark): Which of these processes can produce a new allele? A A change in the environment B Asexual reproduction C Mutation D Selective breeding Your answer [1]
June 2018, Paper 4 Higher, Q10 (1 mark): Why is the process of meiosis important in making gametes? A The cells produced are diploid. B The cells produced are genetically identical. C The cells produce
June 2018, Paper 4 Higher, Q11 (1 mark): What is a genome? A A description of the number of chromosomes in an organism. B All the proteins that one organism can produce. C A store of seeds to preserve
June 2018, Paper 4 Higher, Q12 (1 mark): A harmful protein can cause pain in the joints. A new treatment is being developed to stop the protein causing pain. What effect would this treatment have on th
June 2018, Paper 4 Higher, Q18(a) (2 marks): Explain the meaning of these terms. Gene Allele [2]
June 2018, Paper 4 Higher, Q18(b)(i) (3 marks): Two people who are heterozygous for retinitis pigmentosa are expecting a baby. Draw a genetic diagram to calculate the probability that the baby will have the c
June 2018, Paper 4 Higher, Q18(b)(ii) (3 marks): If the baby has retinitis pigmentosa, it will have normal colour vision but will not be able to see well in dim light. Explain why. [3]
June 2018, Paper 4 Higher, Q19(a) (2 marks): Describe how sex is determined in humans. You may use a genetic diagram in your answer. [2]
June 2018, Paper 4 Higher, Q19(b) (2 marks): In 2015 there were approximately 698 000 babies born in England and Wales. Calculate how many of these were male. Answer = [2]
June 2018, Paper 4 Higher, Q19(c) (1 mark): There are more females than males living in England and Wales as an average over the whole population. Suggest one reason why there are more females. [1]

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