AQA Biology GCSE Topics 5-7
🇬🇧
In English
In English
Practice Known Questions
Stay up to date with your due questions
Complete 5 questions to enable practice
Exams
Exam: Test your skills
Test your skills in exam mode
Learn New Questions
Manual Mode [BETA]
Select your own question and answer types
Specific modes
Learn with flashcards
Complete the sentence
Listening & SpellingSpelling: Type what you hear
multiple choiceMultiple choice mode
SpeakingAnswer with voice
Speaking & ListeningPractice pronunciation
TypingTyping only mode
AQA Biology GCSE Topics 5-7 - Leaderboard
AQA Biology GCSE Topics 5-7 - Details
Levels:
Questions:
88 questions
| 🇬🇧 | 🇬🇧 |
| Homeostasis definition | The regulation of conditions inside your body to maintain a stable internal environment |
| Function of the nervous system | Allows humans to react to their surroundings and coordinate their behaviour |
| Where is the central nervous system? | Brain and spinal cord |
| What are receptors? | Cells that detect stimuli |
| What are sensory neurones? | Carry information as electrical impulses from receptors to CNS |
| What are motor neurones? | Neurones that carry electrical impulses from the CNS to effectors |
| What are effectors? | Muscles and glands that respond to nervous impulses |
| What are reflexes? | Rapid automatic responses to certain stimuli that don't involve the conscious part of the brain |
| How do reflexes prevent injury? | Reduce the chances of being injured |
| What is the thermoregulatory system? | A centre in the brain containing receptors that are sensitive to the temperature of blood flowing through the brain |
| What happens if the thermoregulatory system detects body temperature is too high or too low? | Receptors detect temperature change System triggers effectors automatically Effectors produce a response to counteract change Body cools down/warms up |
| Body responses produced by effectors when temperature is too high | Sweat gland produces sweat Hair erector muscle relaxed Vasodilation (blood vessels dilate) so blood flows close to skin surface |
| Body responses produced by effectors when temperature is too low | No sweat is produced Hairs erect trapping air to insulate Vasoconstriction (blood vessels constrict) so blood supply is shut off Shiver so muscles contract warming the body through respiration |
| What is the endocrine system? | A system of endocrine glands that produce and secrete hormones |
| What is the pituitary gland? | 'Master gland' producing many hormones that regulate body conditions |
| What do the ovaries do? | Produce oestrogen |
| What do the testes do? | Produce testosterone and produce sperm |
| What does the thyroid do? | Produces thyroxine which regulates rate of metabolism, heart rate and temperature |
| What does the adrenal gland do? | Produces adrenaline which prepares the body for 'flight or fight' |
| What does the pancreas do? | Produces insulin and regulates blood glucose level |
| Difference between nerves and hormones? | Nerves- fast action, act for a short time, precise areas Hormones- slower action, act for long time, general areas |
| What happens if blood glucose is too high? | Insulin is added by pancreas |
| What does insulin do? | Makes liver turn glucose into glycogen |
| What happens if blood glucose is too low? | Glucagon is added by pancreas |
| What does glucagon do? | Makes liver turn glycogen into glucose |
| What is type 1 diabetes? | Where the pancreas releases little or no insulin |
| What is type 2 diabetes? | Where a person becomes resistant to their own insulin |
| How is type 1 diabetes treated? | Insulin therapy- several injections of insulin are taken throughout the day |
| How is type 2 diabetes treated? | Exercise and a carbohydrate controlled diet |
| What do the kidneys do? | Filter waste products out of your blood |
| What is the name of when glucose, ions and water are absorbed back into the blood? | Selective reabsorption |
| Name three waste products | Urea, ions, water |
| What is urea? | Ammonia from deamination (amino acids being converted into fats and carbohyrates) converted into urea because it's toxic |
| What is ADH? | Anti-diuretic hormone |
| How is ADH released into the bloodstream? | By the pituitary gland |
| What does ADH do? | Monitors the water content of the blood |
| What does kidney failure lead to? | Build up of waste substances leading to death |
| How can kidney failure be treated? | Dialysis treatment |
| How does kidney dialysis work? | A person's blood flows through partially permeable membranes inside a dialysis machine surrounded by dialysis fluid |
| What does the dialysis fluid do? | Has the same concentration as healthy blood so only waste substances diffuse out |
| What may be side effects of of dialysis? | Blood clots or infections |
| What is the point of kidney dialysis? | Buys patient valuable time until an organ donor is found |
| What is the cure for kidney failure? | Kidney transplants |
| What can be an issue of kidney transplants? | Donor kidney can be rejected by patient |
| How is adrenaline secreted? | Secreted by adrenal glands after receiving nervous impulses |
| Effects of adrenaline? | Increases oxygen and glucose supply to brain and muscles, increasing heart rate |
| How is thyroxine secreted? | Released from pituitary gland in response to thyroid stimulating hormone |
| What does thyroxine do? | Regulates the basal metabolic rate |
| What does Auxin control? | Growth near the tips of shoots and roots in response to light (phototropism) and gravity (gravitropism) |
| Where is auxin produced? | Tips of roots and shoots |
| Why do shoots grow towards light? | When a shoot is exposed to light, more auxin accumulates on the shady side. Cells grow faster on the shady side, causing the shoot to curve towards the light |
| Why do shoots grow away from gravity? | When shoots grow sideways, gravity distributes more auxin on the lower side. Cells on the lower side grow faster causing the shoot to curve upwards. |
| Why do roots grow towards gravity? | When a root grows sideways there is more auxin on the lower side. In roots, the extra auxin inhibits growth causing the cells on top to grow faster and the root to curve downwards. |
| Method to investigate light on cress seeds (Required Practical 8) | 10 cress seeds each into 3 labelled petri dishes lined with moist filter paper Shine light onto one dish from above and two dishes from different directions Leave seeds for 1 week Observe responses |
| Identify independent, dependent and control variables for RP8 | Independent- Light direction Dependent- Plant growth response Control- Light intensity, number of seeds, seed type, temperature, water amount |
| What is sexual reproduction? | Where genetically different cells are produced from two parents |
| What is asexual reproduction? | Where genetically identical cells are produced from one parent |
| What are gametes in animals? | Egg and sperm |
| What is meiosis? | Cells dividing to to form 4 genetically different daughter cells |
| Process of meiosis? | Cells duplicates genetic information Chromosome pairs line up in centre of the cell Pairs are pulled apart so so each new cell has only one copy of each chromosome Chromosomes line up again and are pulled apart in second division Four genetically different daughter cells are produced |
| What do genetic diagrams show? | Possible gamete combinations |
| Where does protein synthesis occur? | In ribosomes |
| Order to write Punnett squares in? | Parent's phenotype Parent's genotype Gamete's genotype Offspring's genotype Offspring's phenotype |
| What is a phenotype? | Characteristics present |
| Name an inherited recessive disorder | Cystic Fibrosis |
| Name an inherited dominant disorder | Polydactyly |
| What is embryonic screening? | Where genes in embryos are screened for genetic disorders |
| What is selective breeding? | Where humans artificially select plants or animals to breed so that particular characteristics are conserved in the population |
| What is an advantage of selective breeding? | Improves yields (meat) |
| What is a disadvantage of selective breeding? | There is a reduction in the gene pool (different alleles in a population) which leads to less disease resistant alleles |
| What does genetic engineering do? | Transfer genes of desirable genetics from one organism's genome to another's. |
| What are abiotic factors? | Non-living factors of the environment e.g. temperature |
| What are biotic factors? | Living factors of the environment e.g. food |
| What is an ecosystem? | The interaction of biotic and abiotic parts of the environment |
| What are the three types of adaption? | Structural e.g. colour of coat, behavioural e.g. migration patterns, functional e.g. lowering metabolism to hibernate |
| What are populations usually limited by? | Amount of food available |
| Method to use quadrats to study the distribution of small organisms | Place 1m^2 at random point within sample area (Use a random no. generator to pick coordinates within area) Count all organisms inside quadrat and record no. and types Repeat as many times as possible Work out mean number of organisms per quadrat Repeat steps above in a second sample area Compare two means |
| Method to use transects to study distribution of organisms along a line | Mark out a line in the area of interest with a tape measure Collect data along the line either using quadrats at intervals or counting organisms that touch the line Record the data Repeat steps above and then compare organisms on different transects |
| Three environmental changes that affect organism distribution | Water availability, temperature, atmospheric gases |
| What are these environmental changes caused by? | Seasonal factors, geographic factors and human interaction |
| What is the water cycle? | The sun makes water evaporate turning it into water vapour Water transpires into from plants contributing to vapour Warm vapour rises and cools condenses to form clouds Water falls from clouds as precipitation onto land It then drains into the sea and the cycle begins again |
| What is the carbon cycle? | CO2 is removed from the environment by green plants and algae during photosynthesis When respiration occurs some carbon is returned to the atmosphere When plants and algae are eaten by animals the carbon moves through the food chain Some carbon is returned to the atmosphere when animals respire When plants, animals and algae die microorganisms (detritus feeders) feed on the remains When these respire carbon is returned to the atmosphere The process begins again |
| What affects the rate of decay? | Temperature, oxygen availability, water availability, number of decay organisms |
| What is biogas? | Gas (mainly methane) produced from anaerobic decay of waste material |
| Brief method to investigate decay | Add lipase solution to test tube Add milk to a different test tube Add phenolphthalein indicator to the milk Add sodium carbonate to the milk turning it alkaline Put both test tubes in a water bath until they reach 30 degrees Add a set volume of lipase solution into the milk solution and start the stopwatch The enzymes will start to decompose the milk beginning a colour change Once the solution has change colour stop the stopwatch and record the time of the colour change Repeat the experiment three times to ensure reliability Repeat the experiment at different temperatures and then calculate the rate of decay for each |