Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
142 Cards in this Set
- Front
- Back
|
What does the amount of cholesterol in blood depend on? |
1. Your diet 2. Inherited factors |
|
|
Where is cholesterol made? |
In the liver |
|
|
Where is cholesterol found? |
In some types of food and in your blood |
|
|
Why is cholesterol important? |
Because your cells need cholesterol to make the cell membrane. |
|
|
Why is having a high cholesterol level dangerous? |
Because if there is too much in the blood it can increase risk of heart disease because it can narrow the arteries |
|
|
What is a healthy diet? |
A diet that contains right balance of different foods for the right amount of energy and the bodies needs |
|
|
What are mineral ions and vitamins needed for? |
Needed in small amounts for the body to function correctly |
|
|
What is a malnourished diet? |
A diet that isn't balanced |
|
|
How can a person lose weight? |
A person will lose weight when the amount of energy they eat is less than the amount they used. |
|
|
What inherited factors can affect a person's health? |
The metabolic rate and the cholesterol levels. |
|
|
What can a poor diet lead to? |
1.) Being overweight or obese 2.) Being underweight 3.) Having a deficiency disease or a condition such as Type 2 diabetes. |
|
|
What is the metabolic rate? |
The rate at which chemical reactions in body's cells are carried out. |
|
|
What is the metabolic rate affected by? |
By the amount of activity or exercise done, the proportion of fat to muscle in body, and inherited factors. |
|
|
What are pathogens? |
Microorganisms which cause infectious diseases. |
|
|
What are the 2 main types of pathogens? |
Bacteria and viruses |
|
|
How do white blood cells protect against pathogens? |
1.) By producing antibodies to protect against particular pathogens. 2.) Producing antitoxins to neutralise toxins produced by pathogens 3.) Ingesting pathogens |
|
|
Name 3 facts about bacteria. |
1.) Very small 2.) May produce toxins to make you feel ill. 3.) Reproduce rapidly |
|
|
What illnesses do bacteria cause? |
Tetanus, tuberculosis, and cholera. |
|
|
Name 2 facts about viruses. |
1.) Smaller than bacteria. 2.) May produce toxins to make you feel ill. |
|
|
How do viruses damage cells? |
By reproducing rapidly once inside living cells. |
|
|
What illnesses do viruses cause? |
1.) Polio 2.) Measles 3.) Flu 4.) Colds |
|
|
How does your body become immune from a pathogen that has infected it before? |
The white blood cells will be sensitised to that pathogen so can produce the specific antibodies very quickly to kill pathogen. |
|
|
What is an example of a vaccine? |
The MMR vaccine used to protect against measles, mumps, and ruebella. |
|
|
Name a advantage of vaccines. |
If a large proportion of the population is immune to a pathogen the pathogen will spread less easily. |
|
|
Who was Semmelweiss? |
He was a doctor who worked in hospitals in the 1840s who recognised how important good hygiene was to prevent infectious diseases spreading from one patient to another so insisted doctors washed hands before examining a patient. |
|
|
What do painkillers do? |
Relieve symptoms of infectious diseases like headaches or a fever. But they don't kill the pathogen. |
|
|
What do antibiotics do? |
They kill infective bacterial pathogens inside the body. |
|
|
What do antibiotics not do? |
They do not kill viral pathogens which live and reproduce inside cells. |
|
|
Why is it hard to develop drugs that kill viruses? |
Because viruses live and reproduce in the body cells it is difficult to kill them without damaging the bodies own tissues. |
|
|
What is an epidemic? |
A local outbreak of disease |
|
|
What is a pandemic? |
A global outbreak of disease. |
|
|
What contributes to epidemics and pandemics? |
1.) Mutations in bacteria and viruses 2.) Global travel 3.) Antibiotic resistance |
|
|
Why are pandemics usually more serious than epidemics? |
Pandemics usually cause more deaths and disrupt society and the economy. |
|
|
Why have many strains of bacteria developed a resistance to antibiotics? |
As a result of natural selection |
|
|
Explain how an antibiotic resistant strain of bacteria occurs. |
1.) Pathogen mutates producing a new strain. 2.) New strain may be resistant to antibiotics. 3.) New resistant strain spreads rapidly because we are not immune to it and there is no effective treatment. |
|
|
What does these new strains of antibiotics mean? |
It means that new antibiotics need to be developed all the time. |
|
|
Which 2 factors contribute to the increase of antibiotic resistant strains of bacteria? |
1.) Overuse of antibiotics. 2.) Prescribing inappropriate antibiotics. |
|
|
What is agar used as? |
Growth medium for microorganisms. |
|
|
Name 3 facts about agar. |
1.) Made from seaweed. 2.) Melts easily and re-solidifies at around 50° 3.) Nutrients added to agar to provide ideal growing conditions for microorganisms. |
|
|
Name the 4 stages of preparing uncontaminated cultures. |
1.) Sterilisation of petri dishes and culture medium. 2.) Sterilisation of inoculating loop. 3.) Transferring Microorganisms. 4.) Sealing the petri dish. |
|
|
Where do you sterilise petri dishes and culture medium and why? |
Autoclave because the high pressures and temperature in the autoclave kill off unwanted microorganisms. |
|
|
After heating the inoculating loop on the bunsen burner to sterilise it what do you not do? |
You do not blow on it or wave it around to cool it as it will pick up unwanted microorganisms. |
|
|
How do you transfer microorganisms? |
By inserting the inoculating loop into a container holding microorganisms and transfer to petri dish by wiping loop on the surface of agar. |
|
|
What 3 things do you need to do when sealing the petri dish? |
1.) Secure with tape to prevent microorganisms from the air contaminating the culture. 2.) Clearly label dish on base. 3.) Store upside down so condensation forms in lid not on agar. |
|
|
What is the maximum temperature cultures are allowed to be incubated at at a school or a college and why? |
25° to prevent the growth of a potentially harmful pathogen that grows at body temperature 37°. |
|
|
What does your body need to control? |
1.) Temperature 2.) Water content 3.) Ion content 4.) Blood sugar (glucose) levels |
|
|
Which 3 ways does water leave the body? |
1.) Lungs by breathing out. 2.) Skin by sweating to cool down. 3.) Kidneys by urine. |
|
|
How are ions carried? |
Water |
|
|
How are ions lost? |
1.) Skin when sweating. 2.) Kidneys by urinating. (Excess ions only.) |
|
|
How is glucose used up? |
When converted to energy. |
|
|
What are hormones? |
Chemicals that are produced by glands. |
|
|
What do hormones do? |
1.) Coordinate many processes within body. 2.) Regulate functions of many organs and cells. 3.) Usually travel to their target organs in the bloodstream. |
|
|
The 7 hormones involved in menstrual cycle cause... |
...an egg to be released every month from the ovaries ...changes in the thickness of the womb lining. |
|
|
Where are the hormones involved in the menstrual cycle produced? |
In the pituitary gland in the brain and the ovaries. |
|
|
What does FSH stand for? |
Follicle Stimulating Hormone |
|
|
What does FSH from the pituitary gland cause? |
1.) An egg to mature in the ovaries. 2.) The ovaries to produce oestrogen |
|
|
What does the oestrogen in the menstrual cycle do? |
1.) Inhibits further production of FSH. 2.) Causes the production of LH. |
|
|
What does the LH hormone stand for? |
Luteinising Hormone |
|
|
What does the LH from the pituitary gland in the menstrual cycle do? |
Stimulates the release of the egg. |
|
|
How can you increase your fertility with hormones? |
Women who don't produce enough FSH can be given FSH and LH in a fertility drug to stimulate eggs to mature. |
|
|
How do you use hormones to reduce fertility? |
Can be given oestrogen and progesterone given in birth control pills to prevent FSH production so eggs don't mature. |
|
|
Why do birth control pills contain a low amount of oestrogen or are only progesterone? |
Because the first birth control pills contained a high amount of oestrogen but made women suffer side effects such as cancer. |
|
|
What is one negative side of fertility drugs? |
Can increase chance of multiple births which can increase the risk of complications during pregnancy. |
|
|
What are the main stages of IVF? |
1.) Mother given FSH and LH to make 7 eggs mature. 2.) The eggs are collected from the mother. 3.) The eggs are fertilised in a lab with father's sperm. 4.) Fertilised eggs develop into embryos (tiny balls of cells). 5.) 1 or 2 embryos are inserted into mother's womb. |
|
|
What does your nervous system allow you to do? |
- React to your surroundings. - Coordinate your behaviour. |
|
|
What does your nervous system consist of? |
- The brain. - The spinal cord. - Nerves (neurones). - Receptors. |
|
|
How do the muscles and glands act as effectors of the nervous system? |
Muscles contract. Glands respond by secreting (releasing) chemical substances e.g hormones. |
|
|
What is the process of the nervous system? |
Receptor Sensory Neurone Relay Neurone Brain and/ or spinal cord Motor Neurone Effector |
|
|
What are receptors? |
They are cells in your sense organs that detect stimuli (changes in your environment). |
|
|
What do light receptor cells have in common with animal cells? |
They both have a nucleus, cytoplasm and cell membrane. |
|
|
What are neurones? |
Neurones are specially adapted cells that carry electrical signals i.e. nerve impulses. |
|
|
What are the three types of neurones? |
- Sensory Neurones - Relay Neurones - Motor Neurones |
|
|
What is the job of a sensory neurone in the nervous system? |
To carry impulses from the receptors to the CNS. |
|
|
Which way does the impulse travel in a sensory neurone? |
The impulse travels towards the cell body. |
|
|
What is the job of the relay neurone in the nervous system? |
To carry impulses from one part of the CNS to another. |
|
|
Which way does the impulse travel in a relay neurone? |
The impulse travels first towards and then away from cell body. |
|
|
What job does the motor neurone have in the nervous system? |
To carry signals from the CNS to the effectors |
|
|
What is the gap between neurones called? |
A synapse |
|
|
Describe how an electrical impulse passes through the synapse. |
1.) An electrical impulse travels through neurone A and reaches the synapse. 2.) It is converted into chemicals, which diffuse across the gap. 3.) Receptors on neurone B detect the chemicals. 4.) An electrical impulse is generated in neurone B. |
|
|
Plants are sensitive to certain stimuli how do they respond to them? |
- Light ( their shoots grow towards the light.) - Moisture ( their roots grow towards moisture.) - Gravity ( roots grow in the same direction as force of gravity.) (shoots grow against force of gravity.) |
|
|
What does the plant hormone called plant growth substance coordinate and control? |
- The growth of shoots and roots. - The flowering of plants. - The ripening of fruit. |
|
|
Why do plants respond to stimuli? |
Because of an unequal distribution of hormones. |
|
|
What is a tropism? |
A plant's response to a stimulus. |
|
|
What does the hormone auxin control in a plant? |
It controls the way in which plants respond to light an gravity. |
|
|
What is phototropism? |
Phototropism is the way in which a plant grows in response to light. |
|
|
How does phototropism work? |
When light hits one side of the plant, more auxin builds up on the darker side of the plant. Excess auxin triggers more growth in these cells, which causes the shoot to bend towards the light. |
|
|
What is gravitopism or geotropism? |
Gravitopism is the way in which a plant grows in response to gravity. |
|
|
What are plant growth hormones used in agriculture and horticulture as? |
- Weedkillers ( to selectively kill weeds by affecting the way in which they grow. - Rooting powders ( to stimulate roots to grow more quickly.) |
|
|
What are drugs? |
Drugs are chemical substances that alter the way the body works. |
|
|
What are statins? |
Statins are drugs used to lower the amount of cholesterol found in the blood. |
|
|
Why do drugs need to be tested? |
- To check if they are toxic. - To see if they are efficient. - To find out what dose is needed. |
|
|
Why are live tissue or animals as models used for drug testing? |
To predict how a drug may behave in humans. But some people disagree with this because they think it's unethical. |
|
|
What is a double blind trial? |
It is when some patients are given a placebo. Neither doctor nor patient knows who has recieved a placebo and who has received the drug until trial is complete. Helps reduce bias in the trial. |
|
|
What was thalidomides original use for? |
To be taken as a sleeping pill. |
|
|
What was the side effect thalidomide had on pregnant women since it had not been tested for morning sickness? |
The women who took the drug gave birth to babies with severe limb abnormalities. So thalidomide was re-tested and is now used to treat leprosy. |
|
|
What has the thalidomide case caused? |
It has resulted in drug-testing becoming much more rigorous. |
|
|
What are some examples of legal drugs? |
Alchol and tobacco |
|
|
What are some examples of illegal drugs? |
Heroin and cocaine which are very addictive. |
|
|
What is the danger of drugs? |
1.) alter the chemical processes in body so people can become dependant on or addicted to the drug. 2.) Illegal drugs e.g. ecstasy, cannabis, and heroin have adverse effects on heart and circulatory system. 3.) suffer withdrawel symptons; physcological e.g. paranoia and/ or physical e.g. sweating or vomiting. 4.) recreational drugs lead to hard drugs. |
|
|
Alchoholic drinks contain ethanol which: |
- Affects nervous system which causes reactions to slow. - Helps people relax - Can lead to lack of self control, unconsiciousness, coma or death when taken in excess - Can lead to liver damage or brain damage in long term. |
|
|
What does tobacco smoke contain and what is the negative side affects of them? |
Carbon monoxide Nicotine They are addictive and carcinogens. |
|
|
Smoking tobacco can cause... |
- Emphysema (damage to alveoli caused by coughing) - Bronchitis - Heart disease - Lung cancer |
|
|
How does smoking when your pregnant affect the baby? |
Carbon monoxide in tobacco smoke reduces the oxygen carrying capacity. In pregnant women this can deprive fetus of oxygen leading to low birth mass. |
|
|
What is the negative effect of the smoke from cannabis? |
It contains chemicals that may cause mental illness in some people. |
|
|
What are some examples of types of drugs athletes can use to enhance their performance? |
- Stimulants that boost bodily functions like heart rate. - Anabolic stimulants that stimulate muscle growth. |
|
|
What do organisms need to survive and reproduce? |
They need materials from their environments and from other organisms that live there. |
|
|
What do plants compete with eachother for? |
- Light - Space - Water - Nutrients from soil |
|
|
When organisms compete which are more likely to be more successful? |
The ones that are better adapted to their environments. And as result the population grows. |
|
|
What do animals compete for? |
- Food - Mates - Territory |
|
|
What are adaptations? |
Features that make an organism well suited to its environment. |
|
|
What features can help animals survive arctic or dry environments? |
- Changes to surface area - Thickness of insualating coat - Amount of body fat - Camouflage |
|
|
What are some adaptions plants can have to survive in dry environment? |
- Changes to surface area (paticuarly leaves that are often reduced in size. - Water-storage tissue - Extensive tissue |
|
|
What are extremeophiles? |
Organisms that live in environments that are very extreme. |
|
|
What environments can extremeophiles become tolerant to? |
High salt levels Tempreture Pressures |
|
|
How do you lose weight? |
Take in less energy than you use. |
|
|
Diets and slimming products will only work if you... |
Eat less fat or carbohydrate Do more excercise |
|
|
What do you need to look for on a slimming product? |
1.) Is it a scientific study 2.) Written by a qualified person 3.) Did it ask a large enough sample of people 4.) Have other studies found similar results |
|
|
What are some examples of your bodies defence system (not white blood cells)? |
Skin Hairs Mucus in respiratory tract. |
|
|
How does skin act as a barrier to anything trying to get into the body? |
Other than being a physical barrier. If it is cut tiny bits of cells help your blood clot quickly to stop anything else getting in. |
|
|
What would happen if something did make it through our bodies defence system? |
The immune system would kick in. |
|
|
What can changes in the environment be due to? |
Living factors- change in a competitor Non-living factors- change in the average temperature or rainfall |
|
|
What can the absence in lichens indicate? |
Air pollution as their growth is affected by sulfur dioxide concentrations in the atmosphere. |
|
|
What can the invertebrate animals indicate and environmental changes? |
Water pollution and are used as indicators of the concentration of dissolved oxygen in water. |
|
|
Efficient food production involves conserving as much energy as possible. This can be achieved by... |
1.) Reducing the number of stages in a food chain 2.) Limiting an animal's movement 3.) Controlling an animal's temperature |
|
|
List three conditions required by microorganisms for decay. |
Warm, most and aerobic (rich in oxygen). |
|
|
In a stable community which two processes are balanced? |
The removal of materials from the environment The return of materials to the environment. |
|
|
Where would you find a stonefly nymph? |
In clean water with high levels of dissolved oxygen |
|
|
Where would you find a rat-tailed maggot? |
In polluted water since it can tolerate low levels of oxygen. |
|
|
What process releases carbon dioxide into the atomosphere? |
Respiration |
|
|
Give two ways in which energy is lost from a food chain. |
Heat loss Waste Movement |
|
|
What do we call the mass of living material in a population? |
Biomass |
|
|
What do the nucleus of a cell contain? |
Chromosomes |
|
|
What are chromosomes made up of? |
DNA |
|
|
What is a section of a chromosome called? |
A Gene |
|
|
What controls the development of different characteristics? |
Genes |
|
|
How many pairs of chromosomes are found in a human liver cell? |
23 pairs |
|
|
How is a useful gene cut from an organisms chromosomes? |
Using an enzyme. |
|
|
Why do genetically modified crops have their genes modified? |
To make them resistant to viruses insects or herbicides. |
|
|
What problems could genetic engineering solve? |
Efficient food production increase yield of a crop Prevent deficiency diseases can include extra nutrients |
|
|
What are some of the cons of gm crops? |
Growing them can affect number of flowers and insects that live by the crops. Not safe to eat. |
|
|
What idea did Lamarck argue? |
If a characteristic was used a lot by an organism would become more developed during its lifetime. Passed into next generation. |
|
|
What does BMI stand for? |
Body Mass Index |
