Biology AQA GCSE Triple Higher Paper 1

Microscope that uses light and lenses to magnify an image

Microscope that uses electrons to form an image in much higher magnification and resolution

RP ONION EPIDERMIS: ___ goes in the middle of a clean slide

___ are used to peel off some epidermal tissue from the onion

___stain is added to the tissue

A ___ ___ is used to lever the cover slip onto the specimen and avoid air bubbles

The slide is clipped onto the ___

The objective lens with the ___ magnification is selected initially

You look through the ___

The ___ ___ ___ is used to roughly focus the image

The ___ ___ ___ is used to increase clarity of the image

Cells that make up all animals and plants

Subcellular structure that contains genetic material that controls cell activities

Subcellular structure that contains enzymes to control reactions, and is where most of the cell's chemical reactions occur

Subcellular structure that controls what enters and leaves the cell

Subcellular structure that is where most reactions for aerobic respiration occur

Subcellular structure that is where protein synthesis occurs

Subcellular structure that in plants provides rigidity and shape

Made of ___

Subcellular structure that stores cell sap - a weak solution of salts and sugars

Subcellular structure that is where photosynthesis occurs

These contain ___ to absorb light

___cells make up a single-celled organism

Single strand of DNA that floats freely in the cytoplasm

Bacterium's cell wall is made of ___

Small rings of DNA

The process by which a cell changes in order to become specialised at its job

Sperm cells have a ___ to help swim to ovum

They also have a ___ ___

They have a lot of mitochondria to provide ___ needed

They have ___ in the head to digest the egg cell membrane

Nerve cells have a long ___ to increase speed of electrical impulses

Fatty ___ ___ to insulate electrical impulses

They have many ___ to form connections with other nerve cells

Muscle cells are ___ to have space to contract and have many mitochondria to provide energy for contraction

Xylem cells are ___ and form long, hollow tubes which allow water and minerals to move easily through the plant

Spirals of ___ around them (a strong waterproof substance that supports the cell

___ cells transport dissolved food through plants

The transport of dissolved sugars around a plant in the (above)

They have a ___ ___ next to them which provides energy to move food through phloem

They have ___ ___ with holes allowing food to move from one cell to the next

The movement of particles from an area of higher concentration to an area of lower concentration

Movement of water molecules across a partially permeable membrane from region of higher concentration to region of lower concentration.

Osmosis RP: Peel the potato and then use a ___ ___ to produce 3 cylinders of potato. Using this makes all of them the same diameter

Use a ___ to trim the cylinders to the same length

Measure the mass of each cylinder using a ___

Place each cylinder into a test tube. The first cylinder should have just 10 cm^3 water, and the other two should have 0.5mol and 0.25mol ___ solution.

Leave overnight to allow osmosis to take place, and then remove the cylinders and roll them on paper towels to remove surface ___

Measure the new mass using a balance and calculate ___

When water moves into a plant cell and causes vacuole to swell, pressing cytoplasm against cell wall and building pressure

Plants need fluid surrounding cells to be ___ to the cytoplasm

If not, water leaves the cells by osmosis and makes them ___ and the plant wilts

If even more water is lost, vacuole and cytoplasm shrink, and eventually cell membrane pulls away from cell. This is ___

Particles move up a concentration gradient.

This happens in root hair cells when absorbing ___ ___

It also happens in the gut when ___ and nutrients enter the bloodstream

___ ___ have a thin membrane for short diffusion distance, large surface area and, in animals, good blood supply to get substances in and out of blood fast

Gas exchange surfaces in animals are often ___ (air moves in and out)

___ in the lungs have walls one cell thick, a moist lining for dissolving gases, an excellent blood supply and a large surface area

___ project from the small intestine to increase SA so digested food is absorbed more quickly into blood. Single layer of surface cells, very good blood supply

___ ___ diffuses into air spaces within leaf

The ___ of the leaf is an exchange surface, covered in stomata which (above) diffuses in through and oxygen and water diffuse out of

The size of these is controlled by ___ ___

These close the stomata if the plant is losing water too quickly by going ___

They open when the plant has lots of water because the cells press against one another in ___and create a space

The evaporation and movement of water away from the plant's leaves from the inside of the plant

The ___ shape of a leaf increases exchange area

___ are the exchange surface in fish

___ containing oxygen enters the fish through the mouth and passes out through the (above)

Each exchange surface is made up of ___ ___ which provide a large SA.

These are covered in ___ increasing the SA even more

There are many ___ to speed up diffusion and a thin layer of surface cells to minimise diffusion distance

Blood flows through in one direction, water in the other. This maintains a large ___ ___ between the water and the blood

Coiled up lengths of DNA molecules that carry large numbers of genes

Used to grow, repair or replace damaged cells

The cell spends most of its life in the ___

The DNA is spread out in long strings and the cell is increasing its number of ___ ___.

The DNA is ___ and forms X-shaped chromosomes - each "arm" of the chromosome is genetically identical

DNA in the chromosomes and their copies condense to become more visible. Membrane around nucleus disappears

Chromosomes line up at centre of cell, spindle fibres attach

Fibres pull chromosomes and copies to opposite ends of cells.

New membranes form around each of the sets of chromosomes (nucleus divided)

Cell membrane pinches in and eventually divides into two daughter cells

___ ___ are undifferentiated and can divide to produce more undifferentiated cells or differentiate into different cells depending on given instructions

They are found in early ___ ___ and these can differentiate into any cell. Adult stem cells can't do this

Could be used to make working ___ ___ for those paralysed with spinal injuries

Or to make ___ producing cells for diabetics

In ___ ___ the embryo is engineered to contain the same genetic information as the patient to prevent the cells being rejected

ISSUES - Might be ___ and make the patient sicker

The ___ are seen as a potential human life

Similar cells are organised into these

These organise themselves into ___

A group of those forms an ___ ___ where multiple (above) work together to perform a particular function

In the stomach, there are three types of tissue. ___ tissue moves the stomach to churn food

___ tissue makes and secretes enzymes

___ tissue covers the inside and outside of the stomach

The stomach is part of the ___ system, which breaks down and absorbs food

These store and provide energy. Made up of units of sugar.

Store energy, make up cell membrane and insulate.

Made up of three molecules of ___ ___ joined to one glycerol

Help build and maintain cells, made up of amino acids

Enzymes are biological ___ that increase the speed of a reaction without being changed or used up

Where does the reaction actually occur on these?

The substrate must be ___ in shape to this (lock and key theory)

When an enzyme connects to its substrate, it is called an ___ ___ ___

When some of the bonds holding the enzyme together break, changing the shape of the active site so the substrate no longer fits

RP: EFFECTS OF pH ON ENZYMATIC REACTIONS: Put a drop of iodine solution in each well of a ___ ___

Iodine turns from orange-brown to ___ ___ when starch is present

Heat beaker of water to __ degrees C

Add 1cm^3 of ___ solution with pH of choice to boiling tube, heat in beaker of water for 5mins

Add 2 cm^3 ___ solution to the tube.

Add 2cm^3 of ___ solution to the tube, mix and start the stop clock.

Every 30s, use a dropping ___ to take a fresh sample from the tube and put a drop in a well

When iodine solution does not change colour, ___ is no longer present: has all been broken down. Repeat with buffer solutions of varying pH to see how it affects time taken

Starch, proteins and fats are molecules too ___ to pass through walls of digestive system

Digestive enzymes break them down into smaller ___ molecules

Breaks down starch into maltose and other sugars, such as dextrin. Made in salivary glands, pancreas and small intestine.

Convert proteins into amino acids. Made in stomach, pancreas and small intestine.

Convert lipids into glycerol and fatty acids. Made in the pancreas and small intestine.

Produced in liver and stored in gall bladder

___ food leaving stomach as it's too acidic for enzymes in small intestine to work properly

___ fats for a larger surface area for enzymes to act on

Food is chewed by teeth and mixed with ___ for swallowing, and amylase is produced by salivary glands

In the oesophagus, ___ pushes food into the stomach

In stomach, ___ acts upon proteins, holding and churning food as it's mixed with enzymes

___ releases enzymes into small intestine, and smaller soluble food molecules are released into the bloodstream (from the SI)

Water absorbed from undigested food in the ___ ___

Material left is stored as ___ in the rectum then passed out through the anus

Preparing a food sample: Break up food with a ___ ___ ___

Add ___ ___ and stir with a glass rod. Filter.

Testing for sugars: Transfer 5cm^3 of food sample to test tube and set water bath to ___ degrees C

Add some ___ reagent using a pipette, and heat for 5 minutes

If the food sample contains reducing sugar, solution turns from ___ to green, yellow or brick red

Starch test: Transfer 2cm^3 of food sample to test tube, and add ___ solution.

If starch is present, the colour of the solution will change from ___ ___ to blue-black.

Protein test: Transfer 2cm^3 of food sample to test tube, and add ___ reagent.

If protein is present, solution will turn from blue to ___

Lipid test: Prepare sample of food. Add ___.

If sample contains lipids, a ___ ___ ___ forms.

Blood cells that carry oxygen from lungs to body cells.

They have a ___ disc shape = large surface area for absorbing oxygen.

They also have no ___ = more room to carry oxygen.

They contain ___.

In the lungs, this binds to oxygen, and in body tissues, the ___ splits up to release oxygen to cells.

Blood cells that defend against infection.

Small fragments of cell that help blood clot.

Carries everything in blood, eg. urea, other components of blood, nutrients, carbon dioxide, hormones, proteins, antibodies, antitoxins.

Vessels that carry blood away from heart at high pressure

Have walls that are strong, thick, and elastic and a small ___.

Have layers of muscle to make them strong, and ___ ___ to allow them to stretch and spring back

Vessels that carry blood very close to cells in body to exchange substances.

Have ___ walls 1 cell thick to allow diffusion

Vessels that carry blood back to heart at low pressure

Have a bigger ___ to help blood flow despite low pressure.

Have ___ to keep blood flowing in right direction.

System made up of heart, blood vessels and blood.

The blood flows into the ___ ___ first.

It comes from the ___ ___ (from the body) and the pulmonary vein (from the lungs.)

The atria contract, forcing blood into ____

These contract, forcing blood into ___ ___ (right side of heart, to lungs) and aorta (left side, to body) out of the heart.

The ___ ___ has a thicker wall because it pumps blood at a higher pressure and therefore needs more muscle to do so.

The sides of the heart are separated by the ___ which stops oxygenated and deoxygenated blood mixing.

Mostly made out of ___ tissue

Has ___ so blood flows in the right direction

Has ___ ___ that branches off the aorta and surround the heart to provide supply of oxygenated blood.

___ ___ then return deoxygenated blood to the right atrium.

Heart rate is controlled by a group of cells in the right atrium wall that act as a ___

They produce small ___ ___ which spread to surrounding muscles, causing contraction

Device implanted into skin that has a wire going to heart. Produces current to keep heart beating regularly. ___ ___

Over time, valves in the body might become stuff, leak, or not open properly, making the heart less ___

Can be replaced with ___ valves (require medication to prevent blood clots but last a long time)

Can also be replaced with ___ valves (don’t require medication but only last 12-15 years.)

___ hearts require lots of machinery and most patients must stay in hospital til a biological transplant

They carry a risk of ___ ___

Can also be used to give a ___ heart a rest so it can recover, reducing strain on it

Heart ___ carry a risk of rejection and the patient will have to take drugs for the rest of their life

In the lungs: air goes in through the ___

This splits into two ___

These split into progressively smaller tubes: ___

End in air sacs called ___ where gas exchange occurs

In leaves: ___ tissue covers the leaf's surface and protects it.

Often secretes a substance that covers the surface of the leaf (___ ___)

___ mesophyll contains lots of chloroplasts that carry out photosynthesis

___ mesophyll contains big air spaces and has a large surface area to make diffusion of gases easier

Diseases caused by pathogens and transmitted form person to person.

Cannot be transmitted.

Pathogens that produce toxins that affect the body and make you feel ill

Pathogens that take over body cells and reproduce inside them, damaging/destroying them

RP Culturing bacteria: Sterilise ___ dishes and nutrient agar.

Heat ___ ___ till red hot in a Bunsen burner (leave this on (leave this on throughout experiment to create a convection current that carries airborne pathogens away.)

Make ___ streaks of bacteria on the agar using the loop.

Fix the lid with adhesive tape to prevent microorganisms from the air ___ the culture, or microorganisms from the culture escaping.

Don't seal all the way around, as oxygen still needs to get in to prevent ___ bacteria growth

Label dish and store ___ ___ to prevent condensation falling on the agar surface

___ for a few days so microorganisms can grow.

Disinfectant safe to use on human skin

Chemicals used inside bodies to kill bacteria

To investigate ___ of disinfectants and antibiotics, add soaked circles of filter paper to the culture plate.

___ ___ ___ around them show where bacteria could not grow.

The isolation of someone with an infectious disease to reduce the chance of the pathogen being passed on

An organism that transmits a pathogen from one organism to another

Causes fever, red skin rash, blindness, brain damage, death.

Spread by ___ in air. There is no treatment, but there is a vaccine.

HIV/AIDS: starts with a mild, ___-like illness. Attacks immune cells.

Hides inside immune system for years after initial symptoms, until the system is so badly ___ it can no longer deal with infections or certain cancers - AIDS

Can be slowed with ___ drugs

Spread by exchange of ___ ___ like sperm and blood, no cure/vaccine

Plant pathogen that causes distinctive mosaic discolouration on leaves as the virus destroys cells

Affects growth as affected areas don't ___

Spread by ___ ___ between diseased and healthy plant material

Good ___ ___ and pest control can help prevent spread

Disease that disrupts balance of natural gut bacteria, causing fever, cramps, vomiting and diarrhoea

In the UK, ___ are vaccinated against it

To prevent food poisoning, keep ___ chicken away from cooked food, avoid washing uncooked chicken, wash hands and surfaces well after handling, cook throughly.

STD that causes thick yellow or green discharge and pain on urination

If untreated, it causes pelvic pain, infertility, and ___ pregnancy

Treated with antibiotics but is becoming ___ so harder to treat

Bacterium that causes crown galls - mass of unspecialised cells that often grow at the join between root and shoot

Bacteria inserts ___ into plant cells and causes a mass of new, undifferentiated, genetically modified cells to grow

Fungal plant disease that causes purple/black spots to develop on leaves, often causing them to turn yellow and drop early

Spread by ___ carried by the wind. Can be reduced by removing and burning affected leaves and stems

Disease caused by protists

Reproduce sexually in the female ___ mosquito and asexually in the human

The female mosquito needs ___ meals of human blood before laying her eggs, so protists are passed into the blood stream

Affects the liver and damages ___ ___ cells. Causes fever and shaking when the protists burst out of these cells

To prevent, use ___ impregnated mosquito nets, and prevent mosquito breeding by removing standing water and spraying water with insecticides to kill larvae

Organ that covers body and acts as barrier, and produces antimicrobial secretions. Also covered with microorganisms that keep you healthy and act as an extra barrier against pathogens

___ seal cuts, preventing pathogens entering the body.

___ is full of hair and produces mucus which traps particles which may contain pathogens or irritate lungs

The ___ and bronchi also secrete mucus.

The lining of these is covered in ___ which beat to waft the mucus up to the back of the throat where it's swallowed

Stomach produces ___ which destroys the microorganisms in the mucus you swallow and most of the ones you ingest

___ ingest the pathogens through phagocytosis and destroy them so they don't make you ill

___ are specific for each type of pathogen, and bind the pathogens together and mark them for destruction

When your white blood cells have produced these once, they can be made very quickly if you encounter the same pathogen again - ___ cells.

Counteract toxins released by pathogens

___ have sharp mouthparts that penetrate the phloem so they can feed on the sugar-rich sap of plants

Attack in large numbers, depriving the plant cells of products of ___ and weakening the plant. Can also act as vectors

Can be destroyed with chemical ___ or by releasing aphid-eating insects like ladybirds

Pests such as ___ ___ and insect larvae live in the soil and feed on plant roots so they can't absorb water and mineral ions effectively

___ ions are needed to covert sugars made in photosynthesis into proteins

A deficiency in these will cause ___ growth and a crop won't be properly produced

___ ions are used to make chlorophyll

Deficiency will cause leaves to turn yellow (___) and slower growth

Cellulose ___ ___ that strengthen cells also help resist invasion by pathogens.

The ___ ___ on a leaf's surface acts as a barrier

Bark on trees and a layer of dead cells on the outside of steams = a protective layer that is hard for pathogens to ___. When dead cells are shed, pathogens fall off with them

___ trees lose leaves in autumn, causing pathogens that affect leaves to fall off too

Many plants produce ___ chemicals that protect against pathogens

These are often used in making medicines - mint and ___-hazel are mild antiseptics

Defences against herbivores: poisons, thorns, hairy stems/leaves to prevent eggs being ___ there

Drooping or curling when ___ to dislodge insects/frighten larger animals.

Mimicry: imitating healthy plants or mimicking ___ eggs on their surface so real ones don't get laid there

Introducing dead/inactive pathogen to body to stimulate immune response

When a large population of the population is immune to a disease, the spread of the pathogen is very much reduced and can even disappear.

Drugs that treat symptoms, but do not cure disease.

Drugs that work inside the body to kill bacterial cells without harming your own cells.

Digitalis and digoxin from foxgloves combat ___ problems

___ originates from a compound found in willow bark

___ ___ discovered the first antibiotic after a spore from the Penicillium mould contaminated one of his cultures

___ fruit is used in Costa Rican medicine and may have antibacterial properties

___ samples are being searched for helpful microorganisms

What does TED stand for? (___, ___, ___)

Trials where a lot of possible new drugs are made and tested in laboratory to see if they're toxic or effective. Then tested on animals

Trials of low doses on healthy people to check for side effects, then on patients to find the optimum dose and see if it's effective

Trial with two groups. One is given the drug, one is given a placebo. Ensures that the medicine is actually effective.

White blood cells known as ___ make antibodies but don't divide

___ cells divide but usually can't make antibodies

Scientists combine the two of these to make a ___

This divides to make cells that all produce the same ___, which are collected and purified

Can be used in ___ tests binding to HCG

Can bind to specific antigens found on pathogens or cancer cells to assist with ___ diseases

Can measure levels of ___ in the blood, eg. in screening for HIV or illegal drug use

Can trigger immune system to recognise, attack, and destroy ___ cells

Can block ___ on the surface of cells to stop them growing and dividing

Don't damage ___ cells and are specific so could treat a wide range of conditions

Not as widely used as initially hoped. Create a lot of side effects, in part due to use of ___ cells for the lymphocyte

Something in your life that makes you more susceptible to a disease/diseases

Explains how on factor influences one another through a biological process

Tumour cells do not respond to the normal mechanisms that control the ___ ___, dividing rapidly and not dying when necessary

Tumours contained in one place, usually within a membrane

Cannot ___ other parts of the body but grow large quickly

Might be dangerous if ___ is caused on an organ (eg, on the brain)

Tumours that can spread around the body, invading healthy tissues (cancers)

Splitting up of original tumour, releasing small clumps of cells into the bloodstream/lymphatic system, which circulate and may lodge in another organ

Therapy where cancer cells destroyed by targeted radiation doses

Chemical therapy used to either stop the cancer cells dividing or make them self destruct

___ is the addictive chemical that is why people enjoy smoking

___ ___ is poisonous and takes up some of the oxygen carrying capacity of the blood

In pregnancy, this might lead to stillbirths, low ___ and premature babies (as the foetus may not grow properly)

The cilia are ___ during smoking, allowing dirt and pathogens to move into the lungs

This turns them from pink to grey and makes smokers more prone to ___

Can lead to breakdown in ___ structure, causing chronic obstructive pulmonary disease

Nicotine makes heart rate increase while other chemicals damage artery lining, increasing risk of ___ ___ ___

When drinking, ___ is absorbed into blood from gut and passes into tissues

Makes thought processes, reflexes and reactions ___ than normal. Can lead to unconsciousness/death

May cause ___ of the liver, where active liver cells are replaced with scar tissue that can't carry out vital functions

Causes brain damage, making it so soft and pulpy that structures are lost and it can no longer ___ properly

Alcohol passes across the ___ into the baby, affecting development of brain and body (Foetal Alcohol Syndrome)

___ ___ penetrates cells and damages chromosomes, causing DNA mutations that might cause cancer

Particularly dangerous when ___ or breathed in as it can penetrate cells directly

The endothermic reaction where carbon dioxide and water are converted into glucose and oxygen

Leaves are broad for a big surface area for ___ to fall on

Thin for short ___ distances

Chlorophyll in the ___ absorb light

Water is brought to the leaf through the ___ and products are removed in the phloem

___ ___ allow carbon dioxide to get to cells and oxygen to leave

___ ___ open and close stomata to regulate gas exchange

___ are aquatic so are adapted to photosynthesising in water.

They absorb ___ ___ dissolved in the water around them. Also dissolves oxygen produced

When one or more of the conditions a plant needs to photosynthesise is in short supply and limits the amount of photosynthesis a plant can manage

Brighter light means a faster ___ of photosynthesis. If there's no light, it cannot happen

As temperature rises, rate increases. But reaction is controlled by ___ which are denatured around 40-50C. If temp is too high, therefore, rate falls.

Increasing the atmospheric CO2 concentration will increase the rate. Usually around ___%

CO2 concentrations rise in the ___ because they respire but don't photosynthesise (due to lack of light) and it's then used up in the morning

Light Intensity RP: Set up boiling tube containing 45cm^3 of ___ ___ ___ solution

Allow to stand for a few minutes, then shake to ___ air bubbles

Cut the top of a piece of pondweed ___

Place in boiling tube using forceps, cut side facing ___

Position the tube so the pondweed is ___cm from the light source

Allow to stand for ___ minutes

Count the number of ___ emerging from the cut end of the stem in one minute

Repeat the count 5 times and take the ___

Repeat at different distances from the light source. Light intensity should be ___ proportional to the square of the distance

Some glucose is used in respiration. Some is built into complex ___ such as cellulose

Stored as starch: glucose is water soluble so could affect ___ but starch isn't and therefore doesn't affect the water balance of the plant

Also used to make ___ ___, combining sugars with nitrate ions from the soil. These are then built up into proteins

Some used to build up fats and oils, often as an energy store in ___ to provide reactants for the new plant to respire as it germinates

___ plants have adapted to live in nitrate-poor soil by obtaining nutrients from insects they catch

You can use a greenhouse to provide a warm atmosphere. ___ greenhouses also control light levels and carbon dioxide concentration

Growing plants in water instead of soil with the perfect nutrient balance instead of soil to make sure nothing slows down growth

The exothermic reaction used to transfer useful energy

The energy released by respiration is used by ___ to synthesise new molecules in the cell

___ respiration: glucose + oxygen -> carbon dioxide + water

___ respiration: glucose -> lactic acid (not enough oxygen for the flucose to fully oxidise)

(Above) respiration in yeast cells: glucose -> ___ + carbon dioxide

This reaction is called:

During exercise, the body needs lots of energy for muscle ___

The body increases aerobic respiration so increases the ___ rate and volume

The heart rate also increases to pump more ___ blood around the body

Sometimes the body cannot get enough oxygen so the glucose is instead converted to ___ ___

This builds up over long periods of vigorous activity and causes muscle ___, stopping the muscles from contracting efficiently

The body must remove the lactic acid from the muscles, creating ___ ___

This is the amount of extra oxygen the body needs after exercise to break down to remove the ___ lactic acid

The lactic acid is transported by the blood to the liver and converted back to ___ by a series of chemical reactions

Reacting with the accumulated lactic acid and removing it from the cells requires ___

The sum of all the chemical reactions in a cell or the body

In plants: ___ is converted into cellulose, starch, or reacted with nitrate ions to make amino acids

In humans: it is converted to ___ which is a storage form of glucose

1 glycerol + 3 fatty acids -> ___ (found in the cell membrane)

Excess proteins are broken down into the chemical ___

This is then excreted by the ___