Key term
AQA GCSE Biology 8461
Bioenergetics
Cell Biology
Topic overviewEukaryotes and prokaryotesAnimal and plant cellsCell specialisation and differentiationMicroscopyGrowing bacteria and aseptic techniqueCalculating bacterial growth, and testing antiseptics and antibioticsChromosomes, mitosis and the cell cycleStem cells in embryos, adults and meristemsTherapeutic cloning, its risks, and cloning plantsDiffusion and the factors affecting its rateSurface area to volume ratio and exchange surfacesOsmosisActive transport
Ecology
Topic overviewLevels of organisation in an ecosystem, and what organisms needCompetition, interdependence and stable communitiesAbiotic factorsBiotic factorsAdaptationsProducers, food chains and sampling with quadrats and transectsPredators, prey and measuring population sizeHow materials are cycledDecompositionWaste management and biodiversityLand use, deforestation and global warmingMaintaining biodiversityTrophic levels and pyramids of biomassTransfer of biomassFactors affecting food securityFarming techniques and sustainable fisheriesRole of biotechnology
Homeostasis and Response
Topic overviewHomeostasisThe nervous system and the reflex arcThe structure of the eye and accommodationMyopia, hyperopia and how they are correctedThe brain and the control of body temperatureHuman endocrine systemInsulin, glucagon and diabetesWater and ion loss, and the production of ureaThe kidneys, ADH and treating kidney failureHormones in human reproductionContraceptionPlant hormones and their uses
Infection and Response
Inheritance, Variation and Evolution
Topic overviewSexual and asexual reproductionMeiosisAdvantages and disadvantages of sexual and asexual reproductionDNA and the genomeDNA as a polymer of four nucleotidesGenetic terms, dominant and recessive allelesPunnett squares, probability and genetic crossesInherited disorders and sex determinationVariationEvolutionSelective breedingWhat genetic engineering is, and what it is used forGM crops, their risks, and the steps of the processCloningDarwin, Lamarck and the acceptance of evolutionSpeciationThe understanding of geneticsEvidence for evolution, and extinctionFossilsResistant bacteriaClassification of living organisms
Organisation
Topic overviewLevels of organisation, and how enzymes workAmylase, proteases and lipasesBile, food tests and the effect of pH on amylaseThe heart, the lungs and double circulationThe pacemaker, the blood vessels and the bloodCoronary heart disease: a non-communicable diseaseHealth issuesRisk factors and causal mechanisms in diseaseSampling, correlation and interpreting risk dataCancerPlant tissues, and transpiration and its rateRoot hair cells, xylem, phloem and stomata
Homeostasis and Response
Water and ion loss, and the production of urea
- 3 things to know
- Paper 2
Overview
How cells swell or shrink by osmosis when body fluids change concentration, uncontrolled water loss through the lungs and skin, why ions must be replaced after sweating, and the kidneys removing excess water, ions and urea in urine.
What you need to know
Answer each one before you reveal it.
Your recallNot started
Key term
What happens to a body cell if the blood plasma around it becomes too concentrated?
Key term
Breathing onto a cold window leaves it misted. Which route of water loss does this show?
Questions from this subtopic
Each one with the model answer underneath.
- 1
What happens to a body cell if the fluid around it becomes too dilute?
Model answer
Water moves into the cell by osmosis, so it swells and may burst.
- 2
What happens to a body cell if the blood plasma around it becomes too concentrated?
Model answer
Water moves out of the cell by osmosis and the cell shrinks.
- 3
Why must the concentration of the body fluids be controlled?
Model answer
So that cells neither gain nor lose too much water by osmosis and can carry on working normally.
- 4
How is water lost from the body through the lungs?
Model answer
It evaporates from the moist lining of the lungs into the air and is breathed out.
- 5
Breathing onto a cold window leaves it misted. Which route of water loss does this show?
Model answer
Loss of water from the body through the lungs in exhaled air.
- 6
Name the three substances lost from the skin in sweat.
Model answer
Water, ions and urea.
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Homeostasis and Response, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.