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What the exam asks for

• Distinguishing the seven life processes and identifying them in examples.
• Using shared features to explain how organisms are grouped.
• Applying species and binomial-naming definitions accurately.
• Following or interpreting a dichotomous key to identify an organism.

Common slips to watch for

• Confusing a single life process with evidence that an organism is alive, or overlooking less visible processes such as excretion.
• Treating organisms that can mate as one species without checking whether their offspring are fertile.
• Misreading a key's paired statements or using a feature that the organism does not have.
• Reversing the order or formatting of genus and species names.

What the exam asks for

• Compare plant, animal and bacterial cells by their structures and functions.
• Relate specialised-cell features to their roles, and distinguish cells, tissues and organs.
• Use magnification and size relationships with consistent units, including conversions between millimetres and micrometres.
• Interpret labelled cell diagrams and measurements, including microscope-style images.

Common slips to watch for

• Confusing a cell wall with a cell membrane, or assigning chloroplasts to animal cells.
• Mixing up which specialised-cell feature supports its function, such as a root hair’s surface area or a red cell’s oxygen transport.
• Rearranging the magnification formula incorrectly or failing to convert image and actual sizes to matching units.

What the exam asks for

• Explain diffusion as net movement down a concentration gradient due to random particle motion.
• Distinguish osmosis as water movement through a partially permeable membrane and connect it to cell changes.
• Explain active transport against a concentration gradient using energy and membrane carrier proteins.
• Apply these processes to membrane movement, including ion uptake by root hairs and water movement in plant tissues.

Common slips to watch for

• Describing diffusion as requiring energy, or as movement of all particles in one direction.
• Calling any water movement osmosis without identifying a partially permeable membrane.
• Reversing the direction of active transport or omitting its energy requirement and carrier proteins.

What the exam asks for

• Recalling the elements in carbohydrates, fats and proteins and the smaller molecules associated with the named biological substances.
• Choosing and describing food tests for starch, reducing sugars, protein and fats or oils.
• Interpreting colour changes and other observations from food-test results.
• Using practical evidence to identify substances in a sample and distinguish a positive result from an inconclusive one.

Common slips to watch for

• Confusing the elements in proteins with those in carbohydrates or fats.
• Naming a food-test reagent without stating the observation that indicates a positive result.
• Mixing up the tests for starch, reducing sugars, protein and fats or oils.
• Recording a colour change imprecisely or claiming a substance is present when the observation does not support it.

What the exam asks for

• Describe enzymes as protein biological catalysts and connect their action to metabolic reactions.
• Explain enzyme specificity through the fit between an enzyme’s active site and its substrate.
• Interpret how temperature and pH affect enzyme activity, including optimum conditions and denaturation.
• Practise planning and evaluating investigations that change temperature or pH while measuring enzyme activity.

Common slips to watch for

• Claiming enzymes are used up in reactions or treating them as non-biological catalysts.
• Saying an enzyme works on any substrate instead of linking specificity to active-site shape.
• Confusing a reduced reaction rate at low temperature with denaturation, or overlooking how extreme pH changes enzyme shape.

What the exam asks for

• State the photosynthesis word equation and explain the roles of light, chlorophyll and raw materials.
• Use leaf diagrams to identify structures and explain how thinness, surface area and listed tissues support photosynthesis.
• Plan or interpret investigations of photosynthesis requirements and limiting factors, using suitable controls and evidence such as starch tests.
• Link photosynthetic products to storage or use, and relate nitrate and magnesium ions to amino-acid and chlorophyll production.

Common slips to watch for

• Leaving light or chlorophyll conditions out of the equation, or treating chlorophyll as a raw material.
• Confusing a factor that limits photosynthesis with a factor that is not being controlled in the investigation.
• Saying plants use nitrate ions to make chlorophyll or magnesium ions to make amino acids.

What the exam asks for

• Relate nutrient sources and functions to a balanced diet, and connect scurvy and rickets to their dietary deficiencies.
• Trace food through the alimentary canal and distinguish ingestion, digestion, absorption, assimilation and egestion.
• Explain how physical digestion increases surface area, and match amylase, proteases and lipase to their substrates and products.
• Use villus features to explain absorption, including the locations of nutrient and water absorption.

Common slips to watch for

• Mixing up absorption of digested nutrients with assimilation into cells, or egestion with excretion.
• Claiming physical digestion changes food molecules chemically, or assigning an enzyme to the wrong food type.
• Confusing the roles of villi and microvilli, or overlooking that some water is absorbed in the colon.

What the exam asks for

• Identify xylem and phloem in plant sections and relate their positions and structures to transport and support.
• Trace water from root hair cells through cortex and xylem to mesophyll, and explain how root hair surface area aids uptake.
• Use transpiration investigation contexts to interpret observations and consider appropriate apparatus, methods and variables.
• Explain translocation in terms of sources, sinks, and movement of sucrose and amino acids through phloem.

Common slips to watch for

• Reversing the transport roles of xylem and phloem, or saying phloem transports only sucrose.
• Treating water movement to mesophyll as translocation rather than movement through root tissues and xylem.
• Assuming a plant part is always a source or always a sink instead of using whether it releases, uses or stores materials.

What the exam asks for

• Trace blood flow through fish single and mammalian double circulations, including the role of the heart’s valves.
• Recognise heart structures in diagrams and distinguish arteries carrying blood away from the heart from veins returning blood to it.
• Compare artery, vein and capillary structure using wall thickness, lumen size and valves, and relate these features to blood pressure and function.
• Explain coronary artery blockage and connect diet and exercise to coronary heart disease risk.

Common slips to watch for

• Reversing the directions of blood flow in arteries and veins, or confusing single with double circulation.
• Describing vessel structure without linking wall thickness, lumen or valves to pressure and function.
• Treating coronary heart disease as a general heart problem rather than blockage of coronary arteries; listing risk factors without explaining risk reduction.

What the exam asks for

• Define a pathogen as an organism capable of causing disease and distinguish pathogens from diseases themselves.
• Explain transmissible disease as pathogen transfer from one host to another.
• Identify direct contact and indirect spread through contaminated sources, animals or air in given scenarios.

Common slips to watch for

• Defining a pathogen as the disease rather than the organism that causes it.
• Calling disease transmissible without identifying how the pathogen passes between hosts.
• Confusing direct contact with indirect spread through contaminated sources, animals or air.

What the exam asks for

• Identify lungs, airways, alveoli, breathing muscles and associated capillaries in diagrams.
• Explain how alveoli’s large surface area, thin walls, blood supply and ventilation support gas exchange.
• Interpret investigations comparing air entering and leaving the lungs, linking observations to gas exchange.
• Relate breathing movements and ventilation to maintaining concentration gradients at the gas exchange surface.

Common slips to watch for

• Confusing the route of air through the lungs or misidentifying alveoli and surrounding capillaries.
• Listing alveolar features without explaining how they support diffusion or maintain a concentration gradient.
• Reversing the changes in oxygen and carbon dioxide between inhaled and exhaled air.

What the exam asks for

• State the aerobic respiration word equation and relate oxygen use to energy release from glucose.
• Describe how temperature affects yeast respiration and interpret results from an investigation.
• Define anaerobic respiration as energy-releasing cellular reactions that do not use oxygen, and compare its energy yield with aerobic respiration.
• Give the word equation for anaerobic respiration in the relevant organism context.

Common slips to watch for

• Including oxygen in the definition of anaerobic respiration or claiming it releases as much energy as aerobic respiration.
• Mixing up aerobic and anaerobic word equations or omitting a required reactant or product.
• Describing a temperature trend without using the investigation results to support the conclusion.

What the exam asks for

• Distinguishing excretion from the removal of carbon dioxide by the lungs and of urea, excess water and excess ions by the kidneys.
• Identifying kidneys, ureters, bladder and urethra in diagrams and images.
• Matching each excretory product to the organ that removes it.

Common slips to watch for

• Confusing the ureters, which carry urine to the bladder, with the urethra, which carries it out of the body.
• Naming the bladder rather than the kidneys as the organ that excretes urea.
• Treating carbon dioxide removal by the lungs as a kidney function.

What the exam asks for

• Tracing electrical impulses through the nervous system and distinguishing its central and peripheral divisions.
• Recognising eye structures and explaining how changing light intensity alters pupil diameter.
• Comparing nervous and hormonal control by speed and duration, and linking hormones to glands and target organs.
• Applying tropism ideas to shoot and root growth, including investigation methods and observations.

Common slips to watch for

• Swapping the central and peripheral nervous system or describing impulses as travelling through the blood.
• Reversing the pupil response to bright and dim light.
• Claiming hormones act faster or for a shorter time than nervous impulses.
• Confusing gravitropism with phototropism or reporting a growth direction without stating the stimulus.

What the exam asks for

• Defining a drug in terms of its effect on chemical reactions in the body.
• Explaining that antibiotics are used against bacterial infections.
• Relating antibiotic resistance in bacteria to reduced antibiotic effectiveness.

Common slips to watch for

• Saying antibiotics treat viral infections.
• Describing resistance as bacteria choosing to adapt because they need to.
• Claiming that resistance makes antibiotics more effective.

What the exam asks for

• Distinguish asexual reproduction from sexual reproduction, including parent number and genetic similarity of offspring.
• Recognise reproductive structures in flower and human diagrams and link each structure to its function.
• Explain fertilisation as fusion of sperm and egg nuclei, and connect reproductive processes to their outcomes.

Common slips to watch for

• Describing asexual offspring as merely similar rather than genetically identical, or giving more than one parent.
• Confusing anthers with stigmas or naming flower parts without matching their functions.
• Describing fertilisation as the joining of whole cells rather than fusion of nuclei.

What the exam asks for

• Link chromosomes, DNA, genes and alleles, and explain how X and Y chromosomes determine human sex.
• Trace how a gene’s base sequence determines an amino-acid sequence and how amino-acid differences lead to different proteins.
• Apply inheritance and genetic-modification ideas to unfamiliar biological contexts and information.

Common slips to watch for

• Confusing a gene with an allele, or treating genes and chromosomes as interchangeable.
• Reversing or overstating the role of X and Y chromosomes in determining sex.
• Mixing up the order from DNA base sequence to amino-acid sequence to protein.

What the exam asks for

• Classify variation as continuous or discontinuous and use the stated examples to distinguish their patterns.
• Use organism features and environmental information to explain how hydrophyte and xerophyte adaptations aid survival.
• Trace natural selection from inherited variation and competition to differential reproduction and allele transfer; distinguish it from selective breeding.

Common slips to watch for

• Treating continuous variation as a set of fixed categories or discontinuous variation as a range.
• Naming an adaptive feature without explaining how it helps survival or reproduction in that environment.
• Claiming individuals evolve because they need to, or confusing human selection with natural selection.

What the exam asks for

• Construct and interpret food chains and webs, identifying producers and tracing energy transfers toward the environment.
• Follow carbon through photosynthesis, feeding, respiration, decomposition, fossil fuel formation and combustion; connect nitrogen processes to plant nitrate uptake and protein production.
• Distinguish populations, communities and ecosystems, and interpret how population change relates to other organisms and the environment.

Common slips to watch for

• Reversing arrows in food chains or treating energy as cycling back to the Sun.
• Confusing carbon-cycle processes with nitrogen-cycle processes, or omitting the role of decomposers.
• Defining a community as one population or an ecosystem as organisms without their interacting environment.

What the exam asks for

• Explain how farming methods increase food production and weigh benefits against environmental costs of large-scale production.
• Link habitat destruction and pollution to biodiversity loss and disruption of food webs.
• Compare effects of sewage, fertilisers, plastics, methane and carbon dioxide in aquatic and terrestrial environments.
• Use evidence to assess conservation and sustainable resource management, including forests, fish stocks and climate-related pressures.

Common slips to watch for

• Listing farming methods without explaining how they increase yield or noting a relevant drawback.
• Treating all pollutants as having the same source or effect, or overlooking nutrient enrichment from fertilisers.
• Defining sustainability without relating resource removal to replenishment, or making conservation claims without evidence.