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

Inheritance, Variation and Evolution

318 questions
23 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, protein synthesis and complementary base pairing, mutations, protein shape and non-coding DNA, 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.
Protein synthesis and complementary base pairing

Where in the cell are proteins made?

Show the answer
On ribosomes.
Genetic terms, dominant and recessive alleles

Under what condition is a recessive allele expressed?

Show the answer
Only when two copies are present, so that no dominant allele is there.
Variation

Why do the offspring of the same two parents differ from one another?

Show the answer
Each inherits a different mixture of the parents' genes, and they may also develop in different conditions.
Selective breeding

What is inbreeding?

Show the answer
Breeding closely related individuals together, which happens when the same characteristics are selected over many generations.
Cloning

Which method of producing identical plants is the older and simpler one?

Show the answer
Taking cuttings.
Speciation

What is speciation?

Show the answer
The formation of a new species.

The 23 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
Protein synthesis and complementary base pairing	Which bases pair, reading the opposite strand, why the strands are complementary, ribosomes and carrier molecules building a protein, and how a changed base order changes the protein.	15
Mutations, protein shape and non-coding DNA	How a finished protein folds into a unique shape for its job as an enzyme, hormone or structural protein such as collagen, how most mutations leave proteins unchanged while some alter their shape, and non-coding DNA switching genes on and off.	12
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, and worked crosses in mice, cats, peas and a recessive disorder.	13
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 wildlife and human health, hopes for overcoming inherited disorders, and the steps of genetic engineering using enzymes and plasmid or virus vectors at an early stage of development.	16
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 318 of the 1,475 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.