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91 Cards in this Set
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What is a healthy diet? |
A healthy diet is balanced and contains the right amount of each of the food groups to match the body's needs. The food groups are:
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Why are carbohydrates needed and where are they sourced? |
Carbohydrates are needed for energy and are sourced from bread, pasta, rice, and sugary foods. |
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Why are fats needed and where are they sourced? |
Fats are also used for energy and they can be sourced in butter, cheese, and fried foods. |
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Why are proteins needed and where are they sourced? |
Proteins are used to build and repair tissue in the body. They can be sourced in meat, fish, cheese, and nuts. |
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Why are mineral ions and vitamins needed and where are they sourced? |
Mineral ions and vitamins are needed in small amounts to keep the body healthy and they are found in fruit and vegetables. |
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What is malnourishment? |
Malnourishment happens if a persons diet is unbalanced. An effect of malnourishment might be that the body lacks some food groups, such as vitamins or minerals. This can lead to deficiency diseases, such as rickets which is caused by a lack of vitamin D. |
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What are the two types of malnourishment? |
There are two types of malnourishment:
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What are overweight people at risk of? |
Overweight people are at risk of type 2 diabetes, obesity, and a high level of cholesterol. Cholesterol can block blood vessels which can lead to heart problems or strokes. Although, some inherited genes can also affect the cholesterol levels. |
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What is metabolic rate and metabolism? |
Metabolism is the cells in your body carrying out chemical reactions. The rate at which these occur is called the metabolic rate. |
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What are the factors that affect the metabolic rate? |
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What is a balanced diet? |
The correct balance of foods and energy. |
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Explain why too much cholesterol is bad for your health. |
Cholesterol blocks blood vessels. This leads to heart attack and strokes. |
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What is a pathogen? |
A pathogen is a microorganism that causes an infectious disease. They include some bacteria and viruses. |
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What is bacteria? |
Not all bacteria are pathogens. When bacteria infect our body, they reproduce rapidly, and may produce poisons, called toxins. They are many different types of pathogenic bacteria, and they will cause different diseases. There are even millions of bacteria on our skin. |
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What are viruses? |
Viruses are much smaller than bacteria. When viruses infect our body, they need to get into our cells. There they will reproduce rapidly and damage our cells, bursting out an causes cells to release toxins, which make us ill. |
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Which doctor realised that washing hands was good for hygiene? |
Before biologists discovered microorganisms, a Hungarian doctor, Ignaz Semmelwiess, recognised that washing hands was important. In his hospital he showed that if doctors washed their hands between patients, the numbers of deaths from infectious diseases decreased. Today washing hands is common practice. |
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Why is it important to grow microorganisms in labs? |
It is important for biologists to grow microorganisms in labs so that they can test treatments, such as antibiotics for disease, or to investigate how effective disinfectants might be at killing bacteria. |
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What are the difference between painkillers and antibiotics? |
Painkillers:
Antibiotics:
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Why do some bacteria become resistant to antibiotics? |
Some bacteria can develop a mutation that gives them resistance to an antibiotic. They will survive by natural selection and form a resistant strain of bacteria. Gradually overtime the entire population of the bacteria will become resistant, and this means that scientists need to develop a new antibiotic. |
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How does the body prevent microorganisms from entering the body? |
These include:
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What happens to a pathogen once it enters the body? |
When a pathogen enters, the immune system comes to the rescue. It uses two types of white blood cell.
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What is a phagocyte and what does it do? |
A phagocyte is a white blood cell.
A phagocyte locate the pathogen, and then engulfs the pathogen, and then ingests it. |
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What is a lymphocyte and what does it do? |
A lymphocyte is white blood cell.
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What does immunity mean? |
Immunity means the ability to resist an infection. This can be acquired in two ways:
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What is natural immunity? |
This happens when we are infected and some of the lymphocytes that produce the antibiotics are retained to deal withe future infections. |
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What is artificial immunity? |
These are given by vaccines, which contain dead or inactive pathogens. This triggers an immune response. The lymphocytes are retained, and will respond rapidly if a future infection by the pathogen occurs. For example the MMR vaccine protects us against future infections of measles, mumps, and rubella. |
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What is a change in the environment called and what does it mean? (Coordination/nerves) |
A change in the environment is called a stimulus. Animals need to respond to these changes by changing their behavior. Selecting the appropriate behavior for the stimulus is called Coordination. |
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Which two systems in the body help coordination? |
The nervous system and The hormone system |
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What is the nervous system made up of? |
The nervous system is made up of nerve cells called neurones.
It is divided into two parts:
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How does the nervous system work? |
The nervous system acts by detecting the stimulus in receptors called sense organs. These send an electrical message called an impulse along nerves to the CNS. The CNS then coordinates an appropriate response, then sends an impulse out to an effector. This brings a response, by either contracting a muscle or releasing a chemical substance from a gland. |
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What are the body's receptors and what do they do? |
We have different receptors for different stimuli.
Sense - Receptor - Stimulus
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What are the body's neurones and what do they do? |
There are three types of neurone:
The junction between the two neurones is called a synapse. |
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What are the reflexes in the body? (not the pathway of the reflex action) |
The reflexes in the body are rapid, protective, and automatic. The pathway taken by the impulses is called to reflex arc (see following flashcard). An example would be, pulling your hand away from a sharp pin is a reflex arc. |
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What is the pathway of the reflex arc?
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What part does the hormonal control play in the control systems of the body? |
The hormonal control system plays a role in controlling the balance of our internal systems. It works by releasing hormones into the blood stream. A hormone is a chemical messenger released in one gland and having its effect on a target organ elsewhere in the body. The effect is generally slower but longer lasting than nerve reflexes. |
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What are the internal conditions of the body that are controlled? |
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How do hormones control the menstrual cycle? |
Hormones control the exact timings that the release of an egg, and the preparation of the womb for pregnancy.
(See page 28 of the AQA Biology Student book for diagram and more information) |
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How can fertility be controlled by contraceptive treatments? |
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How can fertility be controlled by fertility treatments? |
Hormones can also be used to help women become pregnant. Some women have trouble with becoming pregnant because of low levels of FSH and LH. In such cases women can take a fertility drug. This results in eggs being matured and released. |
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What is the process of In Vitro Fertilisation (IVF) |
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What are the benefits and problems of IVF? |
Benefits - families can control when they will start a family, and how many children they will have. IVF allows infertile couples to have children, and embryos can be screened for disorders.
Problems - some people have ethical concerns about controlling fertility and disposing of unwanted embryos. IVF is expensive. There are side effects of the pill, and some women stay on the pill for too long. |
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What stimuli do plants respond to? |
Plants responses are in the form of growth movements called tropism.
Stimulus - Response of shoot - Response of root - tropism
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What does the hormone auxin do in plants? |
Auxin brings about the growth movement in phototropism and gravitropism. The auxin is produced in the shoot and root tips.
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What are the uses of plant hormones? |
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What is a drug and what does it do? |
A drug is a chemical that affects our body chemistry. Drugs are used to treat illness but are also abused by some people. |
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What are the uses of medical drugs and what example are there? |
There are many drugs developed for medical use to treat symptoms and causes of illness. Drugs such as antibiotics, painkillers, and statins. |
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What are statins used for? |
Statins are used to reduce blood cholesterol level. These drugs can reduce the risk of cardiovascular diseases such as heart attacks. |
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What are the trials and rules associated with drug testing? |
Clinical trials -
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How are new drugs tested? |
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What was thalidomide and what was the problem with it? |
Thalidomide was a drug developed as a sleeping pill in the 1950s. It also helped treat morning sickness in pregnant women. The drug was not throughly tested, and it had terrible side-effects. The babies born from the mothers who were using thalidomide had severe limb abnormalities. as a result the drug was banned.
Thalidomide is now used to treat leprosy. |
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What is drug abuse and how does it affect some people? |
Some drugs are illegal and some are legal. Some are more harmful than others.
Drug abuse - where people take drugs for no medical reason. Drugs act by changing the chemical processes in the body, particularly the brain. Some people develop an addiction, and may become dependent on them. This means that they need drugs to maintaining a functioning lifestyle. If these people try and give up the drug, the will get withdrawal symptoms as the body's chemical reactions fail to function fully. |
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What affect does alcohol have on the body? |
Alcohol is a common legal drug. It relaxes people and would not be considered drug abuse. However, high doses of alcohol can impair judgement and lead to reckless behavior, which might affect society as a whole.
Long use of alcohol may lead to serious damage of the liver and other organs. Other legal recreational drugs include caffeine and nicotine. |
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Name two illegal recreational drugs and their effects. |
There are many types of recreational drugs. For example:
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What do adaptations do?
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Adaptations allow plants to survive in environments or changing environments. Such as trees, the bigger the leaves means that more sunlight can be absorbed. |
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Name two adaptations for a polar bear in the arctic and state how it aids survival. |
Small ears - this reduces surface area which reduces heat loss. Thickness of insulating coat - the thick fur coat insulates the body against the cold. Amount of body fat - the polar bear has a thick layer of fat which insulates against heat loss, and can be used in respiration to generate heat. Camouflage - the white fur means that the animal blends in with the environment. |
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Name two adaptations for a camel in the desert and state how it aids survival. |
Long legs - to lift the body high above the hot sand. Thickness of insulating coat - the thin fur in the coat traps less insulating air. Amount of body fat - the thin layer of body fat reduces heat retention. There is a store of fat in the hump that can be used to release energy and water. Camouflage - sandy coloured fur blends in with the background. |
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Name two adaptations for a cactus in a desert and state how it aids it survival. |
Surface area of the - the leaves are spines, which reduces surface area. This in turn reduces water loss. Water storage tissues - stems are swollen to store water. Extensive root system - the roots of the cactus are often shallow but they cover a large area, which allows greater absorption of water when it does rain. |
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Name an extremophile and state how its adaptation aids it survival. |
Whales - They are able to live in great depths of the ocean and withstand the pressure. They have small lungs, which makes them less buoyant, reducing the energy needed to dive. Bacteria - It is able to live in very high temperatures, such as volcanic areas. They are adapted by having enzymes which can still work at high temperatures. |
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What is a population? (in terms of organisms) |
A population is the amount of individual species in one area. |
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What is the distribution? (in terms of organisms) |
The distribution of the population is the range and extent of the area in which the organisms live. |
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What factors affect distribution? |
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What resources do plants compete for? |
Plants compete for:
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What resources do animals compete for? |
Animals compete for:
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What factors affect an organism's environment , which means it needs to adapt? |
Factors that affect if an organism needs to adapt are:
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How do pollutants affect survival and distribution of organisms? |
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What are indicators of air pollution? |
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What are indicators of water pollution? |
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How are pollution levels measured, other than using indicator species? |
Biologists can use a range of sensors that can measure the physical and chemical levels in the environment. Theses include:
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What does a food chain show? |
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What is biomass and how can it be calculated? |
Biomass is the mass of living material. The biomass of each link in the food chain can be calculated by multiplying the number of individuals in that link by the dry mass of one individual.
This can then plot a pyramid of biomass. |
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How do you plot a pyramid of biomass? |
There are rules when plotting a pyramid of biomass:
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What is natural recycling? |
Natural recycling is:
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What is decay and what are the two principal groups of organisms involved? |
Decay is the breakdown of the waste or the body of an organism.
The two principal groups are:
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What is the carbon cycle and what does it do? |
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What is variation and what is it caused by? |
Variation is the differences between individuals. This can also be different species.
Variation can be caused by:
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What are genes? |
Genes are major contributors to variation in organisms.
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How are genes passed on? |
Genes are passed on in gametes, the egg and sperm cells. The two gametes join to form the baby. |
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What is reproduction and what are the two types? |
Reproduction is the production of new individuals of the same species.
The two types of reproduction are:
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How do gardeners use asexual reproduction? |
Gardeners use an asexual technique to produce large numbers of plants. They take cuttings from a parent plant, which will grow into new plants. The advantages are that:
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How does embryo transplant work? |
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How does cloning work? |
An example of cloning is the zorse (this example still works for cloning, and is the exam question that comes up (Jan2012)):
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What is GM? |
Genetically modified organisms are organisms that have had their genes from other organisms, including plants and animals. By adding new genes their genetic code is altered so that they develop with desired characteristics. |
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What are the benefits of GM produce? |
GM produce means that plants characteristics improve their survival the therefore increasing yield. Also, it increases economic value. |
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What are the characteristics transferred by GM? |
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Name 4 arguments for GM crops. |
For:
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Name 4 arguments against GM crops. |
Against:
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What is classification? |
Classification is the similarities and differences between organisms. |
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What are some ecological links between organisms? |
Organisms that share features because they live in the same environment. For example, butterflies and birds both have wings, but the wings are very different in structure. |
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What was Darwin's theory? |
Darwin's theory suggested that species might have developed or evolved from simple life forms that first appeared billions of years ago.
His theory was called evolution by natural selection. Evolution is the gradual change of an organism over time. His idea suggests that gradually one type of organism, called an ancestor, might change over many generations into one or more species. |
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Why was Darwin's theory only gradually accepted? |
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What was an alternative theory to Darwin's? (Hint: JL) |
Jean Lamarck
His theory was explained in the evolution of giraffes:
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