B1 Flashcards (OCR Gateway B)

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Describe factors that increase and decrease blood pressure.
Increase: Smoking, being overweight, drinking too much alcohol and being under lots of stress for a long time. Decrease: Lifestyle changes e.g. eating a balanced diet, doing regular exercise etc or drugs.
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Explain how narrowed arteries increase the risk of a heart attack.
If the coronary arteries become narrowed blood flow to the heart is restricted and the heart muscle receives less oxygen. This causes a heart attack.
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Explain how thrombosis can increase the risk of a heart attack.
A thrombosis is a blood clot. If a thrombosis occurs in an already narrow coronary artery, blood flow to the heart might be blocked completely. If this happens, an area of heart muscle will be cut off from oxygen supply. This causes a heart attack.
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Evaluate different ways of measuring fitness.
Fitness can be measured in 5 ways: Strength, speed, agility and flexibility, together with stamina. Each of these methods would be the most useful to a certain group/type of people e.g. the best measure of fitness for a runner might be speed.
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How does Carbon monoxide affect the blood?
It reduces the amount of oxygen carried in the blood.
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How does nicotine affect a person?
Nicotine is a stimulant that speeds up heart rate and makes blood vessels narrower.
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Recall what proteins, fats and carbohydrates are made from.
Carbohydrates are made up of simple sugars like glucose, fats are mad up of fatty acids and glycerol and proteins are made up of amino acids.
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Explain factors that affect how a balanced diet will vary.
Age: Children and teenagers need more protein but older people need for calcium. Gender: Females need more iron. Physical activity: Active people need more proteins and carbohydrates.
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Explain why protein deficiency is linked to developing counties.
Overpopulation means the demand for protein-rich food is greater than the amount available so not everyone gets enough. There's not a lot of money to invest in agriculture; without good farming techniques it's difficult to produce protein-rich food.
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What is the EAR calculation and explain why results may vary.
EAR(g) = 0.6 x body mass(kg). EAR is an estimate so will not be accurate. EAR varies with age, e.g. teenagers need to eat more protein than adults as they are still growing. It also changes after pregnancy as more protein is needed for the baby.
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What is the BMI calculation and what do the results mean?
BMI = body mass/ (height)2. Below 18.5 - underweight, 18.5-24.9 - normal, 25-29.9 - overweight, 30-40 moderately obese, 40+ severely obese.
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Describe the difference between first and second class proteins.
Animal proteins are first class proteins because the contain all essential amino acids but proteins that don't contain all the essential amino acids, from plants, are called second class proteins.
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What happens to excess carbohydrates in the body?
They are stored in the liver as glycogen or converted into fats.
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What happens to excess amino acids from your diet?
They cannot be stored and are excreted in the urine.
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Recall how pathogens cause the symptoms of disease.
The pathogens produce toxins of create damage to the cells which cause the symptoms of infectious diseases.
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Explain why each pathogen needs specific antibodies.
Every pathogen has unique molecules on the surface of it cells. When your white blood cells come across foreign antigen they start to produce antibodies. The antibodies produced are specific to that pathogen - they won't lock onto another pathogen.
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Explain the process of immunisation.
Immunisation involves injecting dead or weakened pathogens into the body, which carry antigens. They trigger an immune response so your white blood cells produce antibodies to attack the diease. Some of these will remain in the body as memory cells.
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Explain some benefits and risks of immunisation.
Immunisation stops you from getting ill and if most people are immunised then the disease can't spread very far. However there can be short term side effects e.g. swelling, redness or felling ill. Some people think that it can cause other disorders.
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Describe how new treatments are tested.
Computer models are often used first that simulate a human's response to the drug. The drugs are ten developed further by testing them on human tissues. The last step is to test the drug using animals and then humans to make sure it is safe.
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Why are blind trials used in testing new drugs?
One group of people are given the drug, the other a placebo. The scientists can then see the actual difference the drug makes. The people the the placebo think they have the drug and may 'feel' better. this is the placebo effect.
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What are some objections to some forms of drug testing?
Some people dislike drugs being tested on animals in case they get harmed.
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What are diseases that can spread from person to person called?
An Infectious diseases.
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Any organism that causes disease is called a?
Pathogen.
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What substance in the stomach kills pathogens in our food?
Hydrochloric acid.
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An animal which carries an organism that causes disease is called a? Given an example.
A vector e.g. mosquitoes.
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What is accommodation?
Accommodation refers to the process of the eye focusing on near and distant object.
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What is a reflex action?
A reflex action is fast, automatic response to a stimulus.
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What is monocular vision?
Vision in one eye is monocular vision - it provides a wider field of view but poor judgement of distances.
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What is binocular vision?
Vision in two eyes is binocular vision - it provides a narrower field of view but better judgement of distances.
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Recall examples of each drug category.
Depressants - alcohol, solvents and tamazepam. Stimulants - nicotine, ecstasy and caffeine. Painkillers - aspirin and paracetamol. Performance enhancers - Anabolic steroids. Hallucinogens - LSD.
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Explain the basic legal classification of drugs.
Drugs are classified into three main categories, depending on how harmful they are. Class A is the most harmful and Class C is the least harmful.
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Explain the action of depressants and stimulants on nerve synapses.
Stimulants increase the amount of transmitter chemical at some synapses, which increases the frequency of impulses. Depressants bind with receptor molecules on the membrane, blocking the electrical impulses. This decreases brain activity.
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Describe the effects of alcohol on the liver.
Alcohol is broken down by enzymes in the liver. Too much alcohol over a long period of time these toxic products can cause death of liver cells, forming scar tissue that stops blood reaching the liver - this is called cirrhosis.
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One unit of alcohol is equivalent to how many ml of pure alcohol?
10ml
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What is alcohol?
A toxic substance that is broken down by the liver.
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Which area of the brain controls body tempreture?
The Hypothalamus.
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Explain how negative feedback mechanisms maintain a constant internal environment.
Changes the environment trigger a response that counteracts the changes e.g. a rise in body temperature causes a response that lowers body temperature.
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Give 2 examples of plant hormones.
Auxins and Gibberellins.
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What do plant hormones control?
The growth of shoots, roots, flowers and ripening of fruits.
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A directional growth response in plants is called ?
A tropism.
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A plant growth towards a stimulus is a?
Positive tropism.
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A plant growth away from from a stimulus is a?
Negative tropism.
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Explain how auxins bring about shoot curvature in terms of cell elongation.
When a shoot tip is exposed to light, it accumulates more auxins on the side that's in the shade. This makes the calls grow longer, faster on the shaded cell causing the tip to curve.
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Relate the action of plant hormones to their commercial use.
Plant hormones are used in: selective weed killers which only affect broad-leaved plants, rooting powder which makes roots produce rapidly and start growing as new plants and ripening of fruit so they take longer to ripen while be transported.
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Describe how sex in mammals depends on sex chromosomes.
The two mammals mating must have the correct number of chromosomes in their sex cells put together to create the child e.g. humans have 23 chromosomes in their sex cells so when they join together the zygote will have 46 chromosomes.
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What do genetic diagrams show?
The possible genes of offspring.
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Other cards in this set

Card 2

Front

Explain how narrowed arteries increase the risk of a heart attack.

Back

If the coronary arteries become narrowed blood flow to the heart is restricted and the heart muscle receives less oxygen. This causes a heart attack.

Card 3

Front

Explain how thrombosis can increase the risk of a heart attack.

Back

Preview of the front of card 3

Card 4

Front

Evaluate different ways of measuring fitness.

Back

Preview of the front of card 4

Card 5

Front

How does Carbon monoxide affect the blood?

Back

Preview of the front of card 5
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Comments

joycooke

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Great for students who have a concentration span of less than a minute. Thanks

Fairyqueen

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thanks this helped me so much

*Alisha*

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Thank you this is really useful

Haris48

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How do print them off?

Einsteinanutshell

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AWESOME

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