Specifications that use this resource:

Summary of changes

AQA have blended the best of the old specification with some new ideas, new concepts and new approaches to learning. Teachers will find the specification an ideal vehicle to make A-level Biology enjoyable and provide the right level of challenge. It allows a freedom to teach biology in a variety of ways and incorporates key themes and concepts throughout the specification.

It has clearly been put together following consultation with teachers who will see how the minor improvements to the specification have made the AQA specification the ideal choice for students who want to study and excel in biology post-16. Some of the key improvements are the clear signposting of key practical exercises, the removal of the infectious pathogens section and the inclusion of more gene expression. The teaching of practical skills is integrated with the theoretical topics. The clear specification structure builds up from GCSE biology and should provide progression to university or employment. The specification is sufficiently flexible to allow creative teaching. It is the perfect stepping stone to study at undergraduate level as it develops the key skills required to study at degree level and beyond.

The AQA specification is divided into topics, each containing different key concepts of biology. Once the key features of a topic have been developed, applications are considered. While the teaching of practical skills may be integrated with the theoretical topics, they are assessed separately. This allows skills to be developed in a way suited to each individual centre. The AQA specification has integrated a number of required practicals to carry out which contain skills which will be assessed in the written exams.

AQA has reorganised some existing topics into a more coherent order, such as merging of two existing topics to create single topics, which has been done with carbohydrates, cells, and gas exchange.

Learning

What's new - Water

Water is a topic new to the specification (new specification section 3.1.7).

Water is a major component of cells. It has several properties that are important in biology. In particular, water:

  • is a metabolite in many metabolic reactions, including condensation and hydrolysis reactions
  • is an important solvent in which metabolic reactions occur
  • has a relatively high heat capacity, buffering changes in temperature
  • has a relatively large latent heat of vaporisation, providing a cooling effect with little loss of water through evaporation
  • has strong cohesion between water molecules; this supports columns of water in the tube-like transport cells of plants and produces surface tension where water meets air.

What's new - Inorganic ions

Inorganic ions is a topic new to the specification (new specification section 3.1.8).

Inorganic ions occur in solution in the cytoplasm and body fluids of organisms, some in high concentrations and others in very low concentrations.

Each type of ion has a specific role, depending on its properties.

Students should be able to recognise the role of ions in the following topics: hydrogen ions and pH; iron ions as a component of haemoglobin; sodium ions in the co-transport of glucose and amino acids; and phosphate ions as components of DNA and of ATP.

3.1.1 Disease may be caused by infectious pathogens or may reflect the effects of lifestyle

What’s gone

Following feedback from teachers, this section has been removed from the new specification.

3.1.2 The digestive system, 3.1.2 Carbohydrate digestion and 3.1.3 Absorption

Now found in: [3.3.3] [Digestion and absorption].

What’s new

These topics have been brought together and expanded to include the digestion of proteins and lipids, including the action of exopeptidases and endopeptidases in protein digestion and the action of lipase and bile in the digestion of lipids. The role of micelles in the absorption of the products of lipid digestion is also included.

Available resources

Wikibooks: Medical Physiology/Gastrointestinal Physiology/Digestion & Absorption - 1.4 Protein Digestion

What's gone

The structure of the digestive system has been removed; this topic is covered at GCSE.

What's changed

Digestion of carbohydrates has been limited to digestion of starch to maltose by amylase.

What's the same

The concept of digestion as the hydrolysis of polymers into their constituent monomers.

3.1.2 Carbohydrate digestion and 3.2.4 Carbohydrates

Now found in: 3.1.2 Carbohydrates.

What's new

There is no new content.

What's gone

Recall of lactose intolerance is no longer a specification requirement; it could be used as a context to test understanding of digestion.

What's changed

  • The previous content covering both α-glucose and β-glucose, and the polymers formed from them, have been brought from Unit 1 and Unit 2 of the modular specification into a single topic, [3.1.2] [Carbohydrates].

  • The given structure of α-glucose and β-glucose has been expanded to show all the atoms in each molecule.

  • Carbohydrate digestion has been moved from section 3.1.2 of the current specification to section [3.3.3] [Digestion and absorption]- of the new specification.

What's the same

The following topics remain unchanged:

  • the formation of glycosidic bonds between these monomers to form disaccharides and polysaccharides

  • the relationship between the basic structure and functions of starch, glycogen and cellulose in animals and plants

  • qualitative tests for reducing sugars, non-reducing sugars and starch.

3.1.2 Proteins

Now found in: 3.1.4 Proteins.

What's new

The role of hydrogen bonds, ionic bonds and disulfide bridges in maintaining the structure of proteins.

What's gone

No material has been deleted.

What's changed

There are no changes other than any new content added.

What's the same

  • The general structure of amino acids.
  • The formation of peptide bonds between amino acids to form dipeptides and polypeptides.
  • The relationship between primary, secondary, tertiary and quaternary protein structure.
  • The qualitative test for proteins.

3.1.2 Enzyme action; Enzyme properties

Now found in: 3.1.4.2 Many proteins are enzymes.

What's new

The effect of enzyme concentration on the rate of enzyme action.

Students should be able to appreciate how models of enzyme action have changed over time.

What's gone

Recall of the lock-and-key model of enzyme action, which is covered at GCSE.

What's changed

There are no changes.

What's the same

  • The induced-fit model of enzyme action.
  • Lowering of activation energy through the formation of enzyme-substrate complexes.
  • The effect of substrate concentration, temperature, pH, competitive inhibitors and non-competitive inhibitors on enzyme action.

3.1.3 Plasma membranes – lipid structure

Now found in: 3.1.3 Lipids.

What's new

The term ester bond to describe the bond formed by the condensation of glycerol with a fatty acid.

What's gone

No content has been deleted.

What's changed

No further changes have been made.

What's the same

  • The formation of triglycerides and phospholipids.
  • Saturated and unsaturated fatty acids.
  • The qualitative test for lipids.

3.2.2 DNA is an information carrying molecule. 3.2.5 Replication of DNA and the cell cycle

Now found in: 3.1.5 - Nucleic acids are important information-carrying molecules.

What's new

The term phosphodiester bond between nucleotides.

Available resources

YouTube: 3.4.1 Explain DNA Replication

What's gone

No content has been deleted.

What's changed

  • These two topics have been brought together from Unit 1 and Unit 2 of the modular specification, to provide coherent coverage.
  • The structure of RNA has been moved to this section from Unit 4 of the modular specification.

What's the same

  • The structure of a DNA and RNA nucleotides.
  • DNA as a double helix held together by hydrogen bonds between specific base pairs.
  • The semi-conservative replication of DNA.

3.4.2 ATP provides the immediate source of energy for biological processes

Now found in: 3.1.6 ATP.

What's new

  • The basic structure of ATP as a molecule of ribose, a molecule of adenine and three phosphate groups.
  • The roles of ATP hydrolase and ATP synthase in the hydrolysis and synthesis of ATP.
  • The role of ATP has been expanded to indicate the knowledge that can be assessed.

What's gone

No content has been removed.

What's changed

The location of this topic.

What's the same

The structure and role of ATP in providing energy for biological processes.

3.1.3 Cells, 3.1.3 Cholera and 3.2.4 Cells

Now found in: 3.2.1 Cell structure.

What's new

The structure of viruses has been added. Viruses are acellular and non-living. The structure of virus particles to include genetic material, capsid and attachment protein.

What's gone

In response to teacher feedback, recall of cholera and oral rehydration solutions has been removed. These topics could be used as a context for questions testing assessment objective 2.

What's changed

In response to feedback from teachers, topics from Unit 1 and Unit 2 of the modular specification have been brought together.

What's the same

  • The structure and ultrastructure of animal and plant cells.
  • The function of named organelles.
  • The ultrastructure of prokaryotic cells.
  • Optical and electron microscopes.
  • Magnification and resolution.
  • Cell fractionation and centrifugation to separate cell components.
  • Use of an optical microscope.
  • Estimating size.

3.1.3 The structure of plasma membranes enables control of the passage of substances across exchange surfaces

Now found in: 3.2.3 Transport across cell membranes.

What's new

There is no new content.

What's gone

No content has been deleted.

What's changed

No further changes have been made.

What's the same

  • The basic structure of plasma membranes.
  • Exchange by diffusion.
  • Osmosis and active transport.
  • Co-transport exemplified by glucose.
  • Sodium ions in the small intestine.

3.1.4 The lungs and lung function and Gas exchange

Now found in: 3.3.2 Gas exchange.

What's new

Students should be able to appreciate the relationship between surface area to volume ratio and metabolic rate.

What's gone

The course of infection, symptoms and transmission of pulmonary tuberculosis.

The effect of fibrosis, asthma and emphysema on lung function. Although these could be used as context for questions for the new section 3.2.2.

What's changed

In response to teacher feedback, the two topics from Unit 1 and Unit 2 of the modular specification have been brought together.

What's the same

  • The relationship between size and surface area (in [3.3.1] [Surface area to volume ratio]).
  • Gas exchange in a single-celled organism, an insect, a fish and the leaves of a dicotyledonous plant.
  • The structure of mammalian lungs and the mechanism of breathing.

3.1.5 Functioning of the heart, 3.2.4 Haemoglobin and 3.2.7 Mass transport

Now found in: 3.3.4 Mass transport.

What's new

The mass flow hypothesis of translocation in plants.

What's gone

Uptake of water by, and transport of water across, the roots of plants.

The biological basis of heart disease.

What's changed

Three related topics have been brought together.

The following have been moved to 3.6.1.3 Control of heart rate (A-level only):
  • Myogenic stimulation of the heart and transmission of a subsequent wave of electrical activity.
  • Roles of the sinoatrial node (SAN), atrioventricular node (AVN) and bundle of His.
The biological basis of heart disease has been removed, but students will still be expected to:
  • analyse and interpret data associated with specific risk factors and the incidence of cardiovascular disease
  • evaluate conflicting evidence associated with risk factors affecting cardiovascular disease.

What's the same

  • The structure of the heart.
  • The cardiac cycle.
  • Blood vessels.
  • Cardiovascular diseases.
  • The uptake and unloading of oxygen by haemoglobin.
  • Tissue fluid.
  • The cohesion-tension of water transport in plants.

3.1.6 Mammalian blood possesses a number of defence mechanisms

Now found in: 3.2.4 Cell recognition and the immune system.

What’s new

  • How HIV causes the symptoms of AIDS.
  • Why antibiotics are ineffective against viruses.
  • The ELISA test.

Available resources

Sumanas, Inc: Enzyme-Linked Immunoabsorbent Assay (ELISA)

Animation of the ELISA test.

What's gone

No content has been deleted.

What's changed

Clarification is given regarding the required knowledge of
  • The role of T helper cells.
  • The humoral immune response.
  • Herd immunity.
  • The use of monoclonal antibodies.

What's the same

  • Antigens-antibody interaction.
  • Cellular immune response.
  • Humoral immune response.
  • Use of vaccines.
  • Use of monoclonal antibodies.

3.2.1 Living organisms vary and this variation is influenced by genetic and environmental factors.

Now found in: 3.4 (overview) and Section 3.4.7 Investigating diversity.

What’s new

There is no new content.

What’s gone

No content has been removed.

What's changed

Only the location has changed.

What's the same

  • The causes of variation may be the result of genetics, the environment or a combination of both (also in Topic 7 Genetics, populations, evolution and ecosystems- introduction).
  • The need for random sampling.
  • Calculation, and understanding, of mean standard deviation as measures of variation within a sample (calculation will not be tested in written papers).

3.2.2 Structure of DNA

Now found in: 3.1.5 Nucleic acids are important information-carrying molecules.

What's new

The term phosphodiester bond between nucleotides.

What's gone

No content has been removed.

What's changed

No other changes have been made.

What's the same

  • The structure of nucleotides and of polynucleotide chains.
  • DNA as a double helix whose strands are held together by hydrogen bonds between complementary bases.

3.2.2 Genes and polypeptides/DNA and chromosomes

Now found in: 3.4.1 DNA, genes and chromosomes.

What’s new

The proteins associated with DNA in eukaryotic chromosomes are named as histones.

What’s gone

No content has been removed.

What’s changed

No other change has been made.

What’s the same

  • The difference between eukaryotic chromosomes and the DNA in prokaryotes.
  • The concept that, in eukaryotes, much of the nuclear DNA does not code for the amino acid sequence of polypeptides.

3.2.2 Meiosis

Now found in: 3.4.3 Genetic diversity can arise as a result of mutation or during meiosis.

What's new

Mutations in the number of chromosomes can arise spontaneously by chromosome non-disjunction during meiosis.

What's gone

No content has been removed.

What's changed

Only the location.

What's the same

The level of understanding, ie that meiosis produces two haploid cells and is a source of variation.

3.2.3 Similarities and differences in DNA result in genetic diversity

What's gone

This section has been deleted from the co-teachable AS/first year of A-level specification.

3.2.4 The variety of life is extensive

What's changed

The three topics in this section have been relocated to assist coherent teaching and learning.

  • Haemoglobin now found in Section [3.3.4] [Mass transport].

  • Β-glucose and cellulose now found in Section [3.1.2] [Carbohydrates].

  • Plant cells now found in Section [3.2.1] [Cell structure].

3.2.5 During the cell cycle, genetic information is copied and passed to genetically identical daughter cells

  • Replication of DNA now found in: 3.1.5.2 DNA replication.
  • Mitosis and the cell cycle now found in: 3.2.2 All cells arise from other cells.

What's new

Calculation of the mitotic index.

Available resources

YouTube: 3.4.1 Explain DNA Replication

Animation of DNA replication.

Science and Plants for Schools: Staining a root tip and calculating its mitotic index

Calculation of mitotic index.

Binary fission in prokaryotic cells involves:

  • replication of the circular DNA and of plasmids
  • division of the cytoplasm to produce two daughter cells, each with a single copy of the circular DNA and a variable number of copies of plasmids.

Being non-living, viruses do not undergo cell division. Following injection of their nucleic acid, the infected host cell replicates the virus particles.

What's gone

No content has been removed.

What's changed

Only the location.

What's the same

  • The detail of DNA replication.
  • The stages of mitosis.
  • The cell cycle.

3.2.6 In complex multicellular organisms, cells are organised into tissues, tissues into organs and organs into systems

This material is now found in section 3.2.1.1 of the new specification.

3.2.7 Factors such as size and metabolic rate affect the requirements of organisms

Now found in: 3.3 Organisms exchange substances with their environment.

What's new

Translocation of organic substances in the phloem of plants.

Available resources

Animation - Phloem Loading - McGraw-Hill Higher Education

Animation of translocation in phloem.

What's gone

  • The structure of a dicotyledonous root.
  • The apoplast and symplast routes of water from root hairs to the xylem.

What's changed

The major change is a rationalisation of related topics into one section of the new specification.

What's the same

  • Size and surface area.
  • Gas exchange.
  • The blood system.

3.2.8 Classification

Now found in: 3.4.5 Species and taxonomy.

What's new

  • The introduction of domain as a taxon above the level of kingdom.
  • The concept of the binomial system is specified, rather than assumed.

Students should be able to appreciate that advances in immunology and genome sequencing help to clarify evolutionary relationships between organisms.

What's gone

No content has been removed.

What's changed

There are no further changes.

What's the same

  • The principles of taxonomy.
  • The definition of the term species.

3.2.9 Originally classification systems were based on observable features

Now found in: 3.4.7 Investigating diversity.

What's gone

Specific recall of DNA hybridisation has been removed.

What's changed

Other than the location, no other change has been made.

What's the same

The investigation of base sequence of amino acids and amino acid sequence of proteins can be used to elucidate relationships between organisms.

3.2.10 Adaptation and selection are major components of evolution

Now found in: 3.4.4 Genetic diversity and adaptation.

What’s new

There is no new content.

What's gone

Difficulties of treating tuberculosis and MRSA as specific examples.

Resistance may also be passed from one species to another when DNA is transferred during conjugation. This is horizontal gene transmission.

What's changed

No other changes have been made.

What's the same

The principles of natural selection.

3.2.11 Biodiversity may be measured within a habitat

Now found in: 3.4.6 Biodiversity within a community.

What's new

The concept of species richness.

What’s gone

No content has been removed.

What’s changed

To aid understanding, the formula for Simpson’s index of diversity (D) has changed to:

Available resources

Simpson's Diversity Index - Barcelona Field Studies Centre

Explanation of Simpson’s index of diversity with simple calculation

What's the same

  • Calculation of index of diversity.
  • Understanding of the relationship between agriculture and diversity – the balance between conservation and farming.

3.4.1 The dynamic equilibrium of populations is affected by a number of factors

Now found in: 3.7.4 Populations in ecosystems.

What's new

The ecological concept of carrying capacity.

What’s gone

Following feedback from teachers about a potential overlap with social geography, the specific consideration of human populations has been removed, ie population growth rate, age population pyramids, survival rates and life expectancy.

What’s changed

No other changes have been made.

What's the same

  • Populations form a community.
  • Ecological niche.
  • Ecological sampling techniques.
  • Effect of abiotic and biotic factors on population size.

3.4.3 Photosynthesis

Now found in: 3.5.1 Photosynthesis.

What’s new

Recall of the enzymes:

  • ATP synthase (which catalyses the condensation of ADP and inorganic phosphate).

  • Rubisco (which catalyses the reaction between carbon dioxide and ribulose bisphosphate to form glycerate 3-phosphate).

  • the production of ATP involves the passage of protons across chloroplast membranes (to match the existing content in aerobic respiration).

What's gone

No content has been removed.

What's changed

The specific explanation of how growers manipulate the environment of their commercial glasshouses has been made less specific, requiring students to consider agricultural practices that overcome limiting factors.

What's the same

The detail of the light-dependent and light-independent reactions.

3.4.4 Respiration

Now found in: 3.5.2 Respiration.

What’s new

In glycolysis:

  • phosphorylation of glucose to glucose phosphate

  • oxidation of triose phosphate to pyruvate.

What's gone

No content has been removed.

What's changed

No other changes have been made.

What's the same

The detail of aerobic and anaerobic respiration.

3.4.5 Energy is transferred through ecosystems and the efficiency of transfer can be measured

Now found in: 3.5.3 Energy and ecosystems.

What's new

The chemical energy store in dry biomass can be estimated using calorimetry.

The net production of consumers ( N ), such as animals, can be calculated as N = I – F + R (where I represents the chemical energy store in ingested food, F represents the chemical energy lost to the environment in faeces and urine and R represents the respiratory losses to the environment).

What's gone

  • Pyramids of numbers, biomass and energy and their relationship to their corresponding food chains and webs is covered at GCSE.
  • Comparison of natural ecosystems and those based on modern intensive farming in terms of energy input and productivity, although this context can still be used.
  • The use of natural and artificial fertilisers is now in section 3.5.4 of the new specification.
  • The use of chemical pesticides, biological agents and integrated systems in controlling pests on agricultural crops

What's changed

There are no further significant changes.

What's the same

  • The relationship between GPP and NPP.
  • The ways in which productivity is affected by farming practices designed to increase the efficiency of energy transfer by simplifying food webs to reduce energy losses to non-human food chain and reducing respiratory losses within a human food chain, ie intensive rearing of domestic livestock.
  • Being able to calculate the efficiency of energy transfers within ecosystems.

3.4.6 Chemical elements are recycled in ecosystems

Now found in: 3.5.4 Nutrient cycles.

What's new

  • The phosphorous cycle.
  • The role of mycorrhizae in facilitating the uptake of water and inorganic ions by plants.

Available resources

Mycorrhizal fungi / Royal Horticultural Society

Myccorhizae and plant growth.

Whats gone

Specific recall of the carbon cycle and global warming, both of which are covered at GCSE level.

What’s changed

No other change has been made.

What's the same

  • The nitrogen cycle (names of individual species of bacteria not required).
  • The use of fertilisers.
  • Leaching and eutrophication.

3.4.7 Succession

Now found in: 3.7.4 Populations in ecosystems.

What’s new

There is no new content.

What’s gone

No content has been removed.

What's changed

No changes have been made.

What's the same

  • Succession from pioneer to climax community.
  • The effect on other organisms and on biodiversity of changes to the environment caused by organisms at each stage of succession.
  • Conservation involves the management of succession.

3.4.8 Genetic variation within a species and the formation of new species

Now found in 3.7.1 Inheritance, 3.7.2 Populations and 3.7.3 Evolution may lead to speciation.

What’s new

In response to feedback from teachers:
  • dihybrid inheritance and autosomal linkage have both been introduced
  • disruptive selection
  • sympatric speciation.

What's gone

No content has been removed.

What's changed

There is now clarification that natural selection results in species that are better adapted to their environment. These adaptations may be anatomical, physiological or behavioural.

What's the same

  • Understanding of dominant, recessive and codominant alleles.
  • Use of fully labelled genetic diagrams to predict the results of crosses.
  • The Hardy-Weinberg principle.
  • Use of the Hardy-Weinberg equation;
  • The process of natural selection;
  • Allopatric speciation.

3.5.1 Stimuli are detected and lead to a response

Now found in: 3.6.1 Stimuli, both internal and external are detected and lead to a response.

What’s new

There is no new content.

What’s gone

No content has been removed.

What’s changed

The following have been moved from 3.1.5 Functioning of the heart

  • Myogenic stimulation of the heart and transmission of a subsequent wave of electrical activity.
  • Roles of the sinoatrial node (SAN), atrioventricular node (AVN) and bundle of His.

What’s the same

  • Tropisms.
  • Taxes.
  • Kineses.
  • Control of heart rate.
  • Structure and function of Pacinian corpuscle.
  • Differences in sensitivity and visual acuity of the retina.

3.5.2 Coordination may be chemical or electrical in nature

Now found in: 3.6.2 Nervous transmission.

What’s new

There is no new content.

What’s gone

No content has been removed.

What's changed

The content of the ‘Principles’ section has been moved to the introductory overview of Section [3.6] of the new specification.

What's the same

The sections 'Nerve impulses' and 'Synaptic transmission' in current specification remain unchanged.

3.5.3 Skeletal muscles are stimulated to contract by nerves and act as effectors

Now found in: 3.6.3 Skeletal muscles are stimulated to contract by nerves and act as effectors.

What’s new

The concept that muscles work in antagonistic pairs against an incompressible skeleton.

What’s gone

No content has been removed.

What's changed

There are no further changes.

What's the same

  • The gross and microscopic structure of skeletal muscle.
  • Ultrastructure of a myofibril.
  • Role of actin, myosin, calcium mions and ATP in myofibril contraction.
  • ATYP and phosphocreatine as energy sources.
  • Structure, location and general properties of fast and slow muscle fibres.

3.5.4 Homeostasis is the maintenance of a constant internal environment

Now found in: 3.6.4.2 Control of blood glucose concentration and 3.6.4.3 Control of blood water potential.

What's new

  • Control of blood water potential.
  • Structure of a nephron.
  • Formation of glomerular filtrate.
  • Maintenance of a sodium ion gradient by the loop of Henle.
  • Reabsorption of water in the distal convoluted tubule and collecting ducts.
  • The role of the hypothalamus, posterior pituitary and ADH in controlling water reabsorption.

Available resources

Kidney - KScience - Animations

Animation of nephron function.

ADH - KScience - Animations

Animation of control of water reabsorption by ADH.

What's gone

Temperature regulation, which is covered in GCSE.

What's changed

Clarification has been given of the extent of understanding expected of students with respect to the roles of insulin and glucagon.

What's the same

  • The principles of homeostasis.
  • The role of the liver.
  • The second messenger model of adrenaline and glucagon action.
  • Causes, and control of, type I and type II diabetes.

3.5.5 Negative feedback helps to maintain an optimal internal state in the context of a dynamic equilibrium. Positive feedback also occurs.

Now found in: 3.6.4.1 Principles of homeostasis and negative feedback.

What’s new

There is no new content.

What’s gone

Control of mammalian oestrus.

What's changed

No other change in content.

What's the same

  • The concept of negative feedback.
  • Diagrammatic representation of negative feedback.
  • Possession of separate mechanisms involving negative feedback controls departures in different directions from the original state.

3.5.6 The sequence of bases in DNA determines the structure of proteins, including enzymes

Now found in: 3.4.2 DNA and protein synthesis and 3.8.1 Alteration of the sequence of bases in DNA can alter the structure of proteins (A-level only).

What’s new

Following revision to the national subject criteria, this topic has been moved to the co-teachable AS/1st year of A-level.

Available resource for new content

Animation: mRNA Synthesis (Transcription) (Quiz 1) - McGraw-Hill

Animation of mRNA production.

What's gone

No content has been deleted.

What's changed

In the second year content, three new types of mutation have been added, inversion, duplication and translocation of bases.

What’s the same

  • The base triplet hypothesis (from [3.4.1] [DNA, genes and chromosomes).
  • The genetic code is universal, non-overlapping and degenerate (from [3.4.1] [DNA, genes and chromosomes).
  • Non-coding DNA.
  • Transcription, involving splicing of mRNA in eukaryotes.
  • Translation of mRNA involving tRNA.

3.5.7 Gene expression is controlled by a number of features

Now found in: 3.8.2 Gene expression is controlled by a number of features.

What’s new

  • Induced pluripotent stem (iPS) cells.
  • Production of iPS from unipotent cells.
  • Use in treating human disorders.
  • Inhibition of transcription by increased DNA methylation and decreased histone acetylation.
  • Epigenetics as a heritable change in gene function without changes to the base sequence of DNA.

Available resources

Epigenetics - Genetic Science Learning Center - University of Utah

What's gone

No content has been removed.

What's changed

There are no other changes.

What's the same

  • Totipotent cells and cell specialisation.
  • In eukaryotes, transcription is stimulated by specific transcription factors that move from the cytoplasm to the nucleus.
  • The effect of oestrogen on transcription.
  • Gene expression and cancer.

3.5.8 Gene cloning technologies allow study and alteration of gene function in order to better understand organism function and design new industrial and medical processes

Now found in: 3.8.4 Gene cloning technologies allow study and alteration of gene function allowing a better understand organism function and design new industrial and medical processes.

What's new

  • The addition of promoter and terminator regions to fragments of DNA that are transferred to another organism.
  • An understanding that sequencing methods are continuously updated and automated.
  • Use of the term ‘variable number tandem repeats (VNTR)’ in genetic fingerprinting.

What's gone

No content has been removed.

What's changed

No other changes have been made to the content.

What's the same

  • Gene cloning and transfer.
  • The use of gene therapy.
  • The use of DNA probes and DNA hydridisation to locate specific alleles of genes and in medical screening, leading to genetic counselling and the possibility of personalised medicine.
  • Outline of the technique, and use of, genetic fingerprinting.

Specifications that use this resource: