a group of similar cells working together to do something 

a group of tissues that work together to so something 

a group of organs working together to do something 

cell, tissue, organ, organ system, organism 

put these in size order:  organ,cell,organism,organ system,tissue

proteins that catalyse chemical reactions in an organism 

the part of the enzyme that a substrate binds with 

Enzymes active site is a specific shape- only certain substrates fit the active site 

Why do enzymes only catalyse specific reactions?

only a substrate that exactly fits an enzymes active site can bind to the enzyme- once the substrate binds, the enzyme can catalyse the reaction 

Describe the lock and key model of enzyme action 

its active site changes shape - substrate won't fit the active site anymore, so the enzyme can't catalyse the reaction anymore 

What does it mean if an enzyme is denatured?

As temperature increases, the rate of an enzyme-catalysed reaction increases. If temperature gets too high, enzymes become denatured and the rate of reaction decreases.

How does changing temperature affect the rate of an enzyme-catalysed reaction?

the temperature and the pH that the enzymes work best

Enzymes have an optimum temperature and optimum pH. What's meant by it?

1) high temperatures 2) a pH value that's either too high or too low

Give two things that causes enzymes to denature?

comparing how long it takes amylase to fully break down a sample of starch solution at different pH levels

Outline how the effect of pH on amylase activity can be investigated

1) put a drop of iodine solution in each well of a spotting tile 2) add 2cm³ of starch solution and 2cm³ of pH 5 buffer solution to a test tube in a water bath at 35°C 3) After 10 minutes, stir in 2cm³ of amylase solution and start timing 4) take a drop from the test tube every 20 seconds and put it into a well - repeat until the iodine solution stays orangey and record the time passed 5) repeat the experiment with a range of pH buffer solutions

Give a brief method for investigating the effect of pH on amylase activity 

a) salivary glands b) oesophagus c) stomach d) liver e) gallbladder f) pancreas g) small intestine     h) large intestine 

Name these organs of the digestive system 

Break down larger food molecules Into smaller, soluble molecules that can be absorbed into the blood

digestive enzymes that catalyse the breakdown of carbohydrates into simple sugars 

the breakdown of starch into simple sugars 

salivary glands, pancreas, small intestine 

Give three places in the body where amylase is produced 

Give three places in the body where proteases are produced 

breakdown of lipids into fatty acids and glycerol 

salivary glands, pancreas, stomach, small intestine 

Give four places in the body where lipases are produced 

produced in the liver and stored in the gallbladder 

Where is bile produced and where is it stored?

Neutralises stomach acid so the digestive enzymes in the small intestine can function at their optimum pH

Bile is an alkaline substance. Explain why this is important for digestion 

turns fats into very small droplets - this creates a large surface area for lipase to act on, increasing the rate of lipid breakdown by lipase 

Bile emulsifies fats. What does this mean and what does it do for digestion?

1) heat a water bath to 80°C      2) put the food sample in a test tube and add a few drops of benedict's solution 3) put the test tube in the water bath for around 5 minutes 4) if sugars are present, the solution changes from blue to green (some sugar), yellow, or brick-red (lots of sugar)

Describe how to test a food sample for sugars 

1) put the food sample in a test tube 2) add a few drops of iodine solution to the test tube 3) if starch is present, the solution changes from orangey to blue-black

Describe how to test a food sample for starch 

1) put the food sample in a test tube 2) add 2cm³ of buiret solution 3) gently shake the test tube 4) if protein is present, the solution changes from blue to violet or purple 

Describe how to test a food sample for protein 

1) put the food sample in a test tube with some distilled water 2) add a few drops of ethanol OR Sudan III stain to a test tube 3) gently shake the test tube 4) if lipids are present, a cloudy emulsion forms (ethanol) or a separate red layer forms at the top (Sudan III stain)

Describe how to test a food sample for lipids 

a) trachea b) lung c) bronchus d) bronchioles e) alveoli surrounded by capillary network 

a) pulmonary artery b) pulmonary vein c) left atrium d) left ventricle e) right ventricle f) right atrium  g) vena cava h) aorta 

tip : valves stop blood flowing in the wrong direction 

a) deoxygenated blood is pumped by the heart to the lungs where it gains oxygen and loses carbon dioxide - oxygenated blood flows back to the heart b) oxygenated blood is pumped by the heart to the rest of the body where it loses oxygen and gains carbon dioxide - deoxygenated blood flows back to the heart 

Describe the two circuits of the double circulatory system 

carries deoxygenated blood from the body to the heart 

contracts to pump deoxygenated blood to the lungs via the pulmonary artery 

it flows through the capillary network around the alveoli and gas exchange happens:              a) oxygen diffuses out of the alveoli into the blood b) carbon dioxide diffuses out of the blood into the alveoli 

Describe what happens to deoxygenated blood that's pumped to the lungs 

carries oxygenated blood from the lungs to the heart 

contracts to pump blood to the body via the aorta 

supply heart muscles with oxygenated blood 

a group of cells in the hearts right atrium act as a pacemaker and controls the person's resting heart rate 

What controls a person's resting heart rate? 

How can an irregular heart beat be corrected?

What are the three types of blood vessel found in the body? 

carry high blood pressure away from the heart 

1) thick muscular walls to withstand high pressures 2) they have elastic fibres so they can stretch under pressure then recoil to push blood along 3) they have a narrow lumen to maintain a high pressure 

Describe three ways that the arteries are adapted for their function 

carry blood close to cells so substances can be exchanged 

1) very thin walls so substances diffuse over a short distance, improving the rate of diffusion   2) they have permeable walls that let substances in and out 

Describe two ways that capillaries are adapted for their functions 

1) they have valves to stop the blood flowing in the wrong direction 2) they have a large lumen to allow blood to flow easily

Describe two ways that veins are adapted for their function

Red blood cells, white blood cells, plasma, platelets 

What are the four main components that make up blood? 

1) they contain haemoglobin, a protein that binds to oxygen 2) they don't have a nucleus so it can store more haemoglobin 3) their biconcave shape gives a larger surface area for oxygen absorption and flexibility for fitting in capillaries 

Describe three ways that red blood cells are adapted to their function 

help to protect the body against infection 

prevent bleeding by helping blood to clot 

What's the function of platelets in blood?

a liquid that carries everything in blood 

1) Red blood cells 2) White blood cells 3) platelets 4) carbon dioxide 5) proteins 6) hormones 7) Urea 8) dissolved nutrients (e.g, glucose and amino acids)

Give eight things that are carried by plasma in blood

when layers of fatty materials builds up in coronary arteries and narrow them, reducing blood flow through them and so reducing the supply of oxygen to the heart muscle

stents are used to hold open the coronary arteries of people with coronary heart disease - this improves blood flow in the coronary arteries and so improves the supply of oxygen to the heart muscle, reducing the risk of a heart attack

Describe how stents can reduce the risk of a heart attack in people with coronary heart disease

1) short recovery time after surgery to insert them 2) they can quickly have a positive effect 3) they can stay in place and work for a long time 

Give three advantages of using stents to treat people with coronary heart disease 

1) surgery comes with a risk of infection 2) surgery complications (e.g, heart attack) 3) blood clots can form inside stents and cause heart attacks 

Give three disadvantages of using stents to treat people with coronary heart disease 

Statins are drugs that can reduce the levels of cholesterol in the blood, which slows the build up of fatty materials in arteries. Statins are used to: 1) help prevent coronary heart disease 2) reduce the risk of a heart attack in people with coronary heart disease 

Describe what statins are and give two uses of statins 

1) they're taken as pills - no surgery is required 2) they can reduce the risk of strokes and heart attacks as well as coronary heart disease 

Give two advantages of using statins to lower blood cholesterol 

1) they take weeks to lower blood cholesterol 2) people need to remember to take them for the rest of their lives 3) possible side effects 

Give three disadvantages of using statins to lower blood cholesterol 

1) valve doesn't open fully - the heart works harder to pump the blood through the faulty valve    2) valve becomes leaky - blood can flow in the wrong direction, so the heart works harder to maintain blood flow

Describe two heart valves faults and the problems they cause  

1) biological valves made from animal tissue 2) mechanical valves made from synthetic materials 

Describe the two types of valve that can be used to replace faulty heart valves 

blood clots are less likely to form on biological replacement heart valves than mechanical ones 

Give one advantage that biological replacement heart valves have over mechanical ones 

usually last longer than biological ones, so they don't need replacing as often 

Give one advantage that mechanical replacement heart valves have over biological ones

1) they're waiting for a heart transplant - it could help to keep them alive until a donor heart becomes available 2) their heart needs to rest and heal, e.g, to recover after heart failure 

Describe two reasons why someone might be given an artificial heart 

1) they help improve the patients general help, making a heart transplant more likely to succeed 2) they give patients more time to do things like spend time with family or friends 

Give two advantages of using artificial hearts to treat heart failure 

1) they're not a permanent solution 2) there's a risk of blood clots forming in an artificial heart, which could cause a stroke        3) surgery is needed to fit an artificial heart, which risks infection and complications 

Give three disadvantages of using artificial hearts to treat heart failure 

the state of physical and mental wellbeing 

1) disease 2) poor diet 3) stress 4) life situations 

Give four factors that can cause ill health 

communicable diseases can spread between organisms but non-communicable diseases cannot spread between organisms 

What's the difference between communicable and non-comminicable diseases?

1) people with weaker immune systems are more likely to get communicable diseases 2) some viruses can trigger some types of cancer 3) severe physical health issues can cause mental health issues 4) immune responses to pathogens can trigger rashes and athsma

Describe four ways that different types of disease can interact 

1) millions of people around the world can die because of non-communicable diseases 2) non-communicable diseases can reduce people lifespans 3) non-communicable diseases can lower people's quality of life 

Give three human costs of non-communicable diseases 

1) health organisations all over the world spend vast amounts of money diagnosing and treating non-communicable diseases 2) non-communicable diseases can cause people to miss work or make them give it up completely 

Give two financial costs of non-communicable diseases

things that are linked to an increased chance of a person developing a certain disease 

some risk factors cause disease, but not all do

1) smoking 2) lack of exercise 3) a high-fat diet 

Give three risk factors for coronary heart disease

Give a risk factors of type two diabetes 

1) liver disease 2) lowered brain function 3) health problems in unborn babies 

Give three things that drinking alcohol is a risk factor for

1) lung cancer 2) lung disease 3) coronary heart disease 4) health problems in unborn babies 

Give four things that smoking is a risk factor for 

masses of cells formed when cells grow and divide uncontrollably 

tumours that stay in one part of the body - they don't invade tissues around them only spread to other parts of the body (not cancers)

masses of cells that invade tissues around them and spread to other parts of the body (cancers)

cells can break off from malignant tumours and enter the bloodstream, spreading them around the body - these cells can then form secondary tumours 

How can malignant tumours spread around the body to form secondary tumours ?

1) obesity 2) smoking 3) exposure to UV rays 

Give three lifestyle risk factors for cancers 

Are there genetic risk factors for some cancers?

Is a plant leaf a tissue, an organ or an organ system?

a) upper epidermis tissue b) palisade mesophyll tissue c) spongy mesophyll tissue d) lower epidermal tissue e) guard cells surrounding a stoma f) phloem and xylem 

Name these parts in the cross section of the leaf 

1) tightly packed cells -> forms a protective layer over a plant           2) transparent -> lets light get to the tissues where photosynthesis happens 3) waxy layer (the cuticle)-> reduces water loss

Give three ways that the structure of a plants epidermal tissue is related to its function 

tightly packed within cells that contain lots of chloroplasts-> where most photosynthesis happens in a leaf

Give one way that the structure of palisade mesophyll tissue is related to its function 

loosely packed cells surrounded by air spaces -> allows gases to diffuse in and out of cells for photosynthesis

Give one way that the structure of spongy mesophyll tissue is related to its function 

1) made up of hollow tubes -> transports water and mineral ions from a plants roots system to its stems and leaves 2) strengthened within lignin -> helps to support a plant 

Give two ways that the structure of xylem tissue is related to its function 

1) made up of tubes of elongated cells with pores in their end walls -> transports dissolved sugars from a plants leaves to the rest of the plant for use or storage 

Give one way that the structure of phloem tissue is related to its function 

The loss of water vapour from the plants surface be evaporation and diffusion

the movement of food ( dissolved sugars) and other substances through a plants phloem tissue 

1) water evaporates from spongy mesophyll cells into the air spaces that surround the cells   2) the water vapour then diffuses through open stomata into the air around the leaf

Describe the process of transpiration at a plants leaf

the continuous movement of water into a plant through its roots, through its xylem tissue and out its leaves 

B2 ORGANISATION

Flashcards

GCSE Biology Lungs, Heart and Blood Notes

8- Exchange and Transport in Animals - GCSE Edexcel Biology

Biology Circulatory Sytem

The Circulatory System

National 5 Biology Unit 2 notes

GCSE biology - Arteries, capillaries, and veins