Inheritance, Variation and Evolution | AQA GCSE Biology, Foundation tier (8461)

Inheritance, Variation and Evolution

282 questions
21 subtopics
Paper 2
Paper 2

Inheritance, Variation and Evolution is examined in Biology Paper 2.

It covers sexual and asexual reproduction, meiosis, advantages and disadvantages of sexual and asexual reproduction, dNA and the genome, dNA as a polymer of four nucleotides, genetic terms, dominant and recessive alleles, punnett squares, probability and genetic crosses, inherited disorders and sex determination, variation, evolution, selective breeding, what genetic engineering is, and what it is used for, gM crops, their risks, and the steps of the process, cloning, darwin, Lamarck and the acceptance of evolution, speciation, the understanding of genetics, evidence for evolution, and extinction, fossils, resistant bacteria and classification of living organisms.

Sample questions from Inheritance, Variation and Evolution

Answer each one closed book first, then open the answer.

Sexual and asexual reproduction

Name the male gamete and the female gamete in animals.

Show the answer
The sperm cell is the male gamete and the egg cell is the female gamete.
Advantages and disadvantages of sexual and asexual reproduction

Give an example of an organism that uses both types of reproduction, and state what each type gives it.

Show the answer
A strawberry plant produces seeds sexually, which gives variation, and spreads by runners asexually, which quickly produces many identical plants.
Genetic terms, dominant and recessive alleles

What is meant by an organism's phenotype?

Show the answer
The characteristics that the organism actually shows.
Inherited disorders and sex determination

How many of the pairs of chromosomes in a human body cell control characteristics only?

Show the answer
22 pairs.
Selective breeding

Once the first generation of offspring has been produced, what is done next?

Show the answer
The offspring that show the desired characteristic are bred together.
GM crops, their risks, and the steps of the process

Suggest why a crop that is resistant to insect attack could reduce the numbers of birds in an area.

Show the answer
Fewer insects survive on the crop, so the birds that feed on those insects have less food.
Speciation

Apart from his theory of speciation, what is Wallace best known for?

Show the answer
His work on warning colouration in animals.
Evidence for evolution, and extinction

How can a new predator lead a species to extinction?

Show the answer
It may kill the species faster than the species can breed, until no individuals are left.

The 21 subtopics

One subtopic is one session. Work down the list.

Subtopic	What it covers	Questions
Sexual and asexual reproduction	Mitosis and meiosis, gametes in animals and flowering plants and their fusion at fertilisation, why sexual reproduction produces variation, and asexual reproduction from one parent by mitosis producing clones.	10
Meiosis	How meiosis halves the chromosome number and fertilisation restores it, where it happens, copying then two divisions giving four different gametes, and mitosis in the growing embryo.	11
Advantages and disadvantages of sexual and asexual reproduction	Variation and natural selection as advantages of sexual reproduction, selective breeding, the speed and efficiency of asexual reproduction in stable conditions, organisms that use both such as malarial parasites, fungi and strawberries, and choosing a type of reproduction for roses, greenfly and fish farms.	17
DNA and the genome	Nucleus, chromosome and gene by size, the double helix and DNA as a polymer, what a gene codes for, and what studying the human genome offers medicine and migration history.	15
DNA as a polymer of four nucleotides	The sugar, phosphate and base of a nucleotide, the four bases A, C, G and T, three bases coding for each amino acid and how many amino acids a sequence codes for, and the alternating sugar and phosphate structure of each strand.	11
Genetic terms, dominant and recessive alleles	Gametes, chromosomes, alleles, genotype and phenotype, characteristics controlled by a single gene, dominant and recessive alleles and when each is expressed, and homozygous and heterozygous organisms.	13
Punnett squares, probability and genetic crosses	Characteristics controlled by several genes, why a cross predicts only probabilities, ratios and percentages from 3:1 and 1:1 crosses, worked crosses in mice and cats, and identifying a recessive allele from a family tree.	11
Inherited disorders and sex determination	Polydactyly and cystic fibrosis, their dominant and recessive alleles, the case for and against embryo screening, the 23 chromosome pairs, XX and XY, and the chance of a boy.	13
Variation	Variation caused by genes, the environment or both, why siblings and cloned plants differ, extensive genetic variation arising from mutations, how few variants affect the phenotype, and how a new phenotype suited to a changed environment can spread quickly.	15
Evolution	The definition of evolution, natural selection and new species, why it acts on populations, simple life forms over three billion years ago, mutations as the source of variation, and the interbreeding test.	12
Selective breeding	Selective breeding or artificial selection and its history, choosing and breeding parents over many generations, characteristics chosen in crops, farm animals, dogs and flowers, inbreeding and its problems, and the effects on variation and food production.	16
What genetic engineering is, and what it is used for	The definition of genetic engineering, where the new gene comes from, engineered crops and insulin from bacteria, cutting out and transferring a gene, and the benefits, objections and risks.	11
GM crops, their risks, and the steps of the process	What genetically modified crops are and the insect and herbicide resistance and higher yields they give, concerns about wild flowers, insects, birds and human health, and hopes of using genetic modification to overcome inherited disorders.	9
Cloning	Tissue culture for conservation and nurseries, taking cuttings, splitting embryos for embryo transplants, and adult cell cloning, from replacing an egg cell nucleus and an electric shock to implanting the embryo, and why the clone matches the nucleus donor.	16
Darwin, Lamarck and the acceptance of evolution	Darwin's observations, the theory of natural selection and On the Origin of Species, why acceptance was slow, the later discovery of genes, and Lamarck's idea of inherited acquired changes.	18
Speciation	Alfred Russel Wallace, his joint writings with Darwin in 1858, his worldwide evidence and work on warning colouration, the impact of Darwin and Wallace's ideas, and speciation as isolated populations become genetically different until they can no longer interbreed.	13
The understanding of genetics	Mendel's breeding experiments on plants and why their importance was missed, the observation of chromosome behaviour, the link between Mendel's units and chromosomes, units renamed genes, the structure of DNA and gene function, and gene theory as the work of many scientists.	15
Evidence for evolution, and extinction	The fossil record and antibiotic resistance as evidence, the discovery of genes, what extinction means, and how environmental change, disease, new predators, competition and low variation cause it.	10
Fossils	What fossils are and where they form, preservation without decay, replacement by minerals and preserved traces, why early life left few, and reading evolutionary trees and common ancestors.	14
Resistant bacteria	Why bacteria evolve rapidly, how mutation and antibiotic use produce and spread resistant strains such as MRSA, slowing resistance by limiting prescriptions, completing courses and restricting farm use, and the cost and slowness of developing new antibiotics.	14
Classification of living organisms	The Linnaean groups from kingdom to species, binomial names and what shared groups show about relatedness, how microscopes and biochemistry changed classification, Carl Woese's three domains of archaea, bacteria and eukaryota, and placing organisms on evolutionary trees.	18

Inheritance, Variation and Evolution is 282 of the 1,322 questions in the guide.Get the guide, £7

How the guide is worked

Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.

Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.

Read the full method, the return schedule and the research behind it.