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B1. 1.1 Diet and Exercise 1) Name the four major nutrient groups, state why we need each and examples -Carbohydrate – energy source- pasta, bread -Fat – energy, make hormones, insulation – butter, cream -Protein – build new cells- meat - Vitamins and Minerals- Growth. Replace damaged tissues and cells- Vitamin D, Calcium 2) What does a healthy diet contain? The right balance of different foods and the right amount of energy.

3) What can too much salt in our diet lead to Increases blood pressure for about 30% of the population

4) Why do we need fibre? To ensure food moves through our digestive systems efficiently. 5) Why do we need water? It is essential to all body processes

6) What does processed food contain High proportion of fat and/or salt. 7) What two nutrients do we need in small amounts to maintain good health? Vitamins Minerals 8) How do you lose weight You use more calories than you eat

9) How do you gain weight You use fewer calories than eat

10) How can you lose calories Exercise

11) Name 4 effects exercise has on your health - Regular exercise keeps you healthy. - It maintains a good metabolic rate. - It requires energy so uses lots of calories. - If they are not used up they are stored possibly as fat.

Metabolic Rate 12) Define metabolic rate? Is the rate at which all the chemical reactions in the cells of the body are carried out. 13) What is a major metabolic retain Respiration which releases energy from the food we eat

14) State three things that affect metabolic rate: - Activity Levels - More energy is needed. - The ratio of fat to muscle in the body - Muscle cells use more energy - Genes (inherited factors)

15) Which gender would normally have a higher rate? Men because they are slightly bigger and have a large proportion of muscle. 16) How does the temperature affect your metabolic rate? The warmer it is the lower are metabolic rate- We use less energy to keep our body temperature at 37oC

Cholesterol 17) What is cholesterol? A fatty substance made in the liver and used in cell membranes. 18) How is it transported By the blood 19) What affects the amount of cholesterol produced It depends on diet and inherited factors. 20) What increases blood cholesterol rates Saturated fats 21) High levels increase the risk of… Disease in heart and blood vessels. 22) What will help to reduce the blood cholesterol levels Monounsaturated and polyunsaturated fats 23) Cholesterol is carried around the body by … Lipoprotein 24) Name the 2 types of lipoprotein - Low density (LDLs) - High density (HDLs). 25) Are HDLs good or bad and why? Good as it carries cholesterol back to liver, helps prevent cholesterol building up. 26) Are LDLs good or bad and why? They are bad as they cause heart disease Carry cholesterol to cells, high levels of LDLs cause fat to build up in the artery. 27) Why should you balance these To have a healthy heart 28) What improve the balance between LDLs and HDLs Monounsaturated and polyunsaturated fats 29) Name two factors that influence blood cholesterol levels? Diet Genes 30) Name three important things in the body cholesterol are used for? Cell membranes Steroid hormones Bile

31) Explain the link between cholesterol and heart disease? If you have a high ratio of LDLs to HDLs you have an increased risk of heart disease. This encourages cholesterol to be deposited in the walls of coronary arteries, Blockage prevents glucose and oxygen reaching the heart muscle so heart muscle cells cannot respire so die. 32) What are statins and cholesterol blockers used for? Explain how each works. Drugs that lower blood cholesterol. Statins block enzyme in liver. Cholesterol blockers reduce dietary absorption. 33) Why do people not like satins They may encourage people to continue eating unhealthy foods rather than following a healthy diet to reduce their cholesterol.

34) How can you change the fat intake in your diet to reduce cholesterol? Eat less saturated fats and more unsaturated

Malnourished 35) What is meant by the term “malnutrition”? Happens when you eat the wrong amount of each type of nutrient. Either too much or too little. 36) Why does a person become Malnourished? Their diet is not balanced 37) Give two signs of malnourishment? Overweight / underweight Deficiency disease 38) How is deficiency disease caused Caused by a lack of vitamins or minerals 39) What are the Health problems that are connected with malnourishment?

- Reduced resistance to infection – the immune system does not work correctly. - Irregular periods in women. 40) How is deficiency disease caused Caused by a lack of vitamins or minerals 41) What can a lack of vitamin c cause Scurvy0- cause problems with skin, joints and gums 42) Name a source of: Saturated fat: Meat, dairy, eggs Unsaturated fat: olive oil, peanuts, corn oil, sunflower oil, oily fish, margarine 43) What is the BMI equation? BMI = mass in kg (Height in m) ²

44) What do their results from the BMI say? Underweight 30 45) What advice do you give to someone who is obese? Eat less fat and sugar Exercise more 46) What diseases are linked to obesity - arthritis (worn joints) - diabetes (high blood sugar) - high blood pressure - Heart disease. 47) What advice do you give to someone who is underweight? Increase calorie intake 48) What does starvation cause? Thinness, wasting muscles, poor immune system & periods to stop. 49) 2 Advantages of Satin

- Can lower cholesterol to zero - Good for people with high cholesterol due to genetics 50) 2 Disadvantages of Satin - Need cholesterol to make hormones etc. - Potentially fatal side effects 51) 2 Advantages of Cholesterol blockers - Good for people with high cholesterol due to diet - Less side effects than satins 52) 2 Disadvantages of Cholesterol blockers -

Can interact badly with other drugs. Can cause diarrhoea.

1.12 Microbes and disease 1) What is a pathogen? Microorganism that causes disease. 2) How do individual pathogens develop resistance? Sometimes a bacterium is produced that is slightly different to the others. This is called a mutation. The mutation might result in the bacteria being resistant to existing antibiotics. When an antibiotic is used, the non-resistant bacteria are killed but a small number of resistant bacteria remain. The resistant bacteria survive and reproduce; this is an example of natural selection. 3) What are bacteria? - A single celled microorganism that has no nucleus (but circular DNA that floats in cytoplasm). This causes disease by reproducing and producing toxins. - Reproduce rapidly; may make toxins but not all cause disease, smaller than plant or animal cells 4) What is an example of bacteria? Typhoid, cholera 5) What is the difference between bacteria and viruses? Viruses are much smaller than bacteria and viruses are not cells but bacteria are 6) What are viruses? Viruses are pathogens. Need to reproduce inside other cells, always damage cells 7) What do viruses produce and what do they do? They produce toxins and they damage the cells in which they reproduce, leading to illness 8) What is an example of a virus? E.g. colds, measles 9) Explain how the following make you ill: Bacteria: Reproduce rapidly and produce toxins Viruses: reproduce inside cells and damage them 10) Explain how vaccination works: Small amount of dead or inactive pathogen injected infection Next time pathogen enters body white blood cells make antibodies faster and in greater numbers - Stimulates memory cells to form 11) Describe the action vaccinations on the body? A vaccine contains a small amount of dead or weak forms of the pathogen. The white blood cells produce antibodies to destroy the pathogen. This makes the person immune to future infection by the pathogen. The white blood cells will recognise the pathogen is it gets into the body and will respond by quickly producing antibodies. -

12) What 3 diseases does MMR vaccine protect from? - Measles - Mumps - Rubella

13) Explain how white blood cells protect you from disease. - Ingest pathogens (phagocytosis) - Once inside the cell, the white blood cell releases enzymes to digest and destroy it. -

Produce antibodies – destroy specific bacteria or viruses

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Produce antitoxins – neutralise toxins released by pathogens

14) Outline the experiments carried out by Ignaz Semmelweiss and explain the contribution of these to modern medicine. Noted death rates on maternity wards much lower when midwives delivered compared to doctors - realised doctors were transferring disease from surgery Encouraged use of chloride of lime to wash hands and kill bacteria - Death rates drastically fell Shows importance of handwashing to prevent spread of infection 15) What impact did Semmelweiss’ research have? He introduced hand washing into hospitals which reduced the number of deaths. 16) How can the following drugs be used to treat disease? Painkillers: relieve symptoms (don’t kill pathogen) Antibiotics: Kill bacteria 17) What are antibiotics? Medicines that help cure diseases caused by bacteria. They kill bacteria inside the body. E.g. Penicillin. 18) Why can’t antibiotics be used to kill viruses? Viruses replicate inside human cells so the antibiotic can’t reach them or would kill the human cell. 19) Why is overuse of antibiotics a problem? Selects for antibiotic resistant bacteria to survive These are hard to treat. 20) How can we reduce this problem? Do not use antibiotics for minor infections Reduce use in agriculture 21) Why are antibiotics used in farming? - Help animals gain weight – less energy spent overcoming infection - Increase profits – prevent spread of infection 22) Explain how antibiotic resistance develops in bacteria. - Bacteria mutate by chance - Bacteria with mutation not killed by antibiotic - These cells can survive to reproduce And pass the gene for resistance to their offspring – population of resistant bacteria increases 23) What is a mutation? Change in a gene

24) Why is mutation in pathogens problematic? Creates new strains that people have no immunity to or are resistant to antibiotics 25) How does immunity develop? Once the white blood cells have destroyed a type of pathogen, you are unlikely to develop the same disease again. This is because the white blood cells will recognise the pathogen the next time it invades the body and produce the right antibodies to kill the pathogen before it can cause illness. 26) What is a sterile culture? Culture of only one type of microorganism. 27) Give 2 reasons it is important to keep cultures sterile. - Other microbes would use up food resources - Other microbes may produce dangerous toxins 28) List 4 precautions you must take when carrying out aseptic technique to grow a sterile culture 1. Sterilise petri dish and culture medium before use 2. Sterilise inoculating loop by passing through a flame 3. Tape lid to prevent contamination from air 4. Work near a flame 29) What temperature should we incubate cultures at in school and why? - 25°C – to prevent growth of human pathogens. 30) How does this compare to industry? Industry higher – faster growth rate. 31) Why would higher temperature be used in industrial situations? Many microbes need high temperatures to grow 32) Why is it at this temperature? Pathogens could accidently be present in the culture dishes, so keeping the temperature at a maximum of 25˚C minimises health risks from them, as they will grow much less at lower temperatures 33) Why must petri dishes be sterilised before use? To kill any unwanted microorganisms and prevent contamination. 34) When using inoculating loops to transfer bacteria what must be done to avoid contamination? It must be sterilised in a Bunsen burner flame 35) Why must petri dishes be taped shut? To prevent contamination from airborne bacteria

1.2 Nerves and Hormones 1) What is a neurone? A cell that transmits electrical nerve impulses, carrying information from one part of the body to another. 2) What three neurones are involved in a reflect action? Sensory, relay and motor neurones Something Really Mental 3) What is the function of the sensory neuron? Carry impulses from the receptor to the spinal cord. 4) What is the function of the relay neuron? Carry impulses through the spinal cord and up to the brain and from the brain back along the spinal cord. 5) What is the function of the motor neuron? Takes impulses from the spinal cord to an effector. 6) What is a stimulus? A change in environment 7) Name the 5 different sense organs Eyes, ears, nose, tongue and skin 8) What is the function of the receptor? Cells that detect stimuli or changes in the environment. E.g. Eyes, ears, tongue, nose, skin. 9) What can a stimulus be? Light, sound, touch, pressure, pain, chemical or a change in position or temperature 10) What do the receptor cells in the following organs respond to? Eyes: light - Tongue: taste Ears: sound; changes in position - Nose: smell Skin: touch, temperature, pressure, pain 11) What is the function of the effector? Can be a muscle that is made to contract or a gland that secretes a chemical for example a hormone. 12) What is the function of the synapse? The junction of two nerve cells 13) What happens here? The nerve signal is transferred by chemicals which diffuse across the gap These chemicals then set off a new electrical signal in the next neurone 14) What are reflexes They are automatic responses to certain stimuli – they can reduce the chance of being injured 15) Describe what happens in a reflex arc: 1. Named receptor detects the stimulus 2. Electrical impulse travels along sensory neurone to central nervous system 3.Chemicals diffuse across a synapse to relay neurone 4. Chemicals diffuse across synapse to motor neurone

5. Impulse reaches effector which responds by contracting if it is a muscle or secreting a substance if it is a gland

16) What is the function of the human nervous system? To detect changes in the environment To co-ordinate and control responses 17) What organs are involved controlling water Lungs (breath); Skin (Sweat); Kidneys (urine) 18) What organs are involved controlling ion content Skin (sweat) Kidneys (urine) 19) Name the two different areas of the nervous system 1. Central nervous system (CNS) Brain and spinal cord This coordinates the response 2. Peripheral nervous system (PNS) Consists of nerves connecting the CNS to the rest of the body (e.g. the optic nerve and the sciatic nerve) 20) Whats the differences between nerves and hormones Nerves Very fast action Act for a short time Act on a precise area

hormones short action Act for a long time Act on a more general area

Hormones 21) What is a hormone? A chemical messenger 22) Where are hormones produced? Glands 23) How do hormones travel around the body? In the bloodstream

The menstrual cycle 24) what is the first stage of a menstrual cycle Day 1 is when the bleeding starts The uterus lining breaks down for about four days 25) what is the second stage of a menstrual cycle the lining of the uterus build up again from day 4 to day 14, into a thick spongy layer full of blood vessels, ready to receive a fertilised egg. 26) what is the third stage of a menstrual cycle An egg is released from the ovary at day 14 27) what is the fourth stage of a menstrual cycle The wall is then maintained for about 14 days

If there is no fertilised egg that has landed on the uterus wall by day 28, the spongy lining starts to break down again and the whole cycle starts again

28) What is the three main hormones involved FSH Oestrogen LH 29) What produces FSH? Pituitary gland 30) What does FSH cause An egg to mature in one of the ovaries 31) What does FSH stimulate The ovaries to produce oestrogen 32) What produces Oestrogen? Ovaries 33) What does Oestrogen cause Pituitary to produce LH 34) What does Oestrogen inhibit The further release of FSH 35) What produces LH? Pituitary gland 36) What does LH stimulate The release of an egg at around the middle of the menstrual cycle 37) What produces progesterone Ovaries 38) What is the role of progesterone? Maintains the uterus lining

Controlling fertility 39)

Which 2 hormones are in the contraceptive pill? Oestrogen and progesterone 40) How do oral contraceptives work? They contain oestrogen to stop production of FSH and progesterone to maintain uterus lining 41) What impact do the hormones in oral contraceptives have on the hormones in the body? The pill contains hormones that have the same effect on the pituitary gland as oestrogen. These hormones stop the pituitary gland making the hormone FSH. This means that no eggs will mature in the ovaries. 42) How have birth control pills changed over time and why?

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The first pills had large amounts of oestrogen. These resulted in women suffering significant side effects such as the formation of blood clots. The pill now contains much lower dosage of oestrogen.

43) 3 Advantages of contraceptive pill - 99% effective - Easy to take - Reduces the risk of getting some types of cancer 44) 4 Disadvantages of contraceptive pill -

Side effects, headaches, nausea, irregular menstrual bleeding and fluid retention - Still a slight chance of getting pregnant - Can forget. - Doesn’t protect against STD’s 45) Which hormones will be included in “fertility drugs”? FSH 46) What happens during in vitro fertilisation (IVF)? The female is given injections of FSH to stimulate the maturation of several eggs. Eggs are then collected just before they are released from the ovary. The eggs are fertilised with sperm outside the body and the fertilised eggs are allowed to divide to form embryos. Some are inserted into the womb. 47) 2 Advantages of IVF - Allow people to have children - Uses own sperm and eggs 48) 4 Disadvantages of IVF - Multiple births - Painful - Expensive - Low success rate

Plant Hormones 49) List three things that plants are sensitive to: 1) Light 2) Gravity 3) Water 50) What is the name of the hormone in plants? Auxin 51) Where is the Auxin produced? Stem and root tips 52) what is the auxins purpose when in the tip of the shoot Causes cell growth. 53) what is the auxins purpose when in the root tips Cause cells to stop growth 54) shoots grow ____ light

Towards 55) When a shoot tip is exposed to light what do the auxins do? The accumulate on the side that’s in the shade than the side that’s in the light. This concludes to the cells that are on the shaded side to grow faster so the shoot bends toward the light. 56) shoots grow ____ gravity Away from 57) What happens if a shoot is growing sideways Gravity produces an unequal distribution of auxin in the tip, with more auxin on the lower side. This causes the lower side to grow faster, bending the shoot upwards. 58) roots grow ____ gravity Towards 59) What happens if a root is growing sideways Gravity produces an unequal distribution of auxin in the tip, with more auxin on the lower side. The extra auxin in the root inhibits growth This means the cells on top elongate faster, bending the shoot downwards 60) roots grow ____ moisture Towards 61) What if there is an uneven amount of moisture on either side of the root? On the side with more moisture it produces more auxin. That side then inhibits growth causing the root to bend in that direction and towards the moisture. 62) What happens if the tip of a shoot is removed? No auxin would be available and the shoot may stop growing 63) What is phototropism? The response of plants to light, Stems grow towards the light. This response to directional light is called phototropism. Plant stems are positively phototropic, that is they grow towards the light stimulus. 64) What is geotropism? The response of plants to gravity. Stems are negatively gravitropic. They grow away from the direction of the force of gravity. Roots are positively gravitropic. They grow in the direction of the force of gravity. 65) How can plant growth hormones be used in agriculture? Selective weed killers, rooting powders and ripening fruit. 66) Explain how plant hormones...