Term
A person will lose weight (body mass) when the amount of energy in the food they eat is less than... |
|
Definition
... the amount of energy used by their body. Energy increases the amount of energy used by the body. |
|
|
Term
A person is malnourished if their diet isn't balanced. A poor diet can lead to... |
|
Definition
- a person being overweight or obese
- a person being underweight
- deficiency diseases or conditions such as Type 2 diabetes
|
|
|
Term
A person's health is affected by 2 main factors. They are... |
|
Definition
- metabolic rate
- cholesterol level
( the amount of cholesterol in your blood depends on your diet and inherited factors) |
|
|
Term
Microorganisms that cause infectious diseases are called pathogens. The two main types of pathogens are... |
|
Definition
|
|
Term
White blood cells help to defend against pathogens by... |
|
Definition
- ingesting pathogens
- producing antitoxins to neutralise toxins from pathogens
- producing antibodies to destroy particular pathogens
|
|
|
Term
By being vaccinated, you can acquire immunity to that particular disease. Explain. |
|
Definition
- Small amounts of inactive or dead pathogen are injected into your body.
- Your white blood cells produce antibodies to destroy the pathogen.
- You have then acquired immunity to this particular pathogen because your white blood cells are sensitised to it, in the same way as if you had previously had the disease.
|
|
|
Term
| Semmelweiss was a doctor who worked in hospitals in the 1840s. He recognised that by washing your hands, you would prevent spreading infectious diseases! this greatly reduced... |
|
Definition
| ... the number of deaths from infectious diseases in hospital. |
|
|
Term
|
Definition
|
|
Term
Some medicines, such as painkillers (e.g. aspirin) only relieve the symptoms of infectious diseases, like headaches and fever. But these medicines don't kill pathogens. However, antibiotics... |
|
Definition
| ... (.e.g penicillin) kill infective bacterial pathogens inside the body. Antibiotics have greatly reduced the number of deaths from infectious bacterial diseases. |
|
|
Term
Name one strain of bacteria, and why it is called a "strain". |
|
Definition
MRSA. It is called a strain because it has developed resistance to antibiotics as a result if natural selection. |
|
|
Term
Antibiotic restraint strains occur when pathogens mutate. Explain. |
|
Definition
- A pathogen mutates, producing a new strain.
- The new strain may be resistant to antibiotics.
- the new resistant strain spreads rapidly because we are not immune to it and there is no effective treatment.
This means that new antibiotics need to be developed all the time! |
|
|
Term
|
Definition
An epidemic is local outbreak of a disease. A pandemic is a global outbreak of disease. |
|
|
Term
Uncontaminated cultures of microorganisms are prepared using the following steps: |
|
Definition
- Sterilisation of petri dishes and culture medium
- sterilisation of inoculating loops
- Transferring microorganisms
- Sealing petri dish
In schools and colleges, cultures are incubated at a maximum of 250C to prevent the growth of potentially harmful pathogens. |
|
|
Term
Your nervous system allows you to... |
|
Definition
- react to your surroundings
- coordinate your behaviour
|
|
|
Term
Your nervous system consists of the following... |
|
Definition
- The brain
- The spinal cord
(these two make up the Central Nervous System (CNS))
- Nerves (neurones)
- Receptors
|
|
|
Term
| Your brain coordinates an appropriate response by sending instructions to effectors. Effectors are either muscles or glands: |
|
Definition
- Muscles respond by contracting.
- Glands respond by secreting (releasing) chemical substances, e.g. hormones.
|
|
|
Term
| Cells called receptors in your sense organs detect stimuli (changes in your environment). Different stimuli are detected by different receptors. What are these receptors and their uses? |
|
Definition
- Receptors in your eyes are sensitive to light.
- Receptors in your ears are sensitive to sound and changes in position, which help you balance.
- Receptors in your nose and on your tongue are sensitive to chemicals, helping you smell and taste.
- Receptors in your skin are sensitive to touch, pressure, pain and temperature.
|
|
|
Term
The information about changes in your environment follows a pathway through your body to produce a response. Explain this pathway. |
|
Definition
- Stimulus
- Receptor
- Sensory neuron
- Central nervous system
- Motor neuron
- Effector
- Response
|
|
|
Term
| Neurones are specially adapted cells that carry electrical signals, i.e. nerve impulses. There are three types of neurone, each with a slightly different function. What are these three types of neurone? |
|
Definition
- Sensory neurones carry impulses from receptors to the CNS.
- Motor neurones carry signals from the CNS to effectors.
- Relay neurones carry impulses from one part of the CNS to another.
|
|
|
Term
| Neurones don't touch each other. There is a tiny gap between called a synapse. Explain the process of connections between neurones. |
|
Definition
- An electrical impulse travels through neurone A and reaches a synapse.
- It is converted into chemicals, which diffuse across the gap.
- Receptors in neurone B detect the chemicals.
- An electrical impulse is generated in neurone B.
|
|
|
Term
| Reflex actions have to be... |
|
Definition
| ... automatic and quick! If you had to think before you act when touching a hot surface, the process would be much slower and you would be burned. |
|
|
Term
Plants as well as animals respond to stimuli (changes in the environment). What four features are plants sensitive to? |
|
Definition
- light - their shoots grow towards the light
- moisture - their roots grow towards moisture
- gravity - roots grow in the same direction as the force of gravity (downwards); shoots grow against the force of gravity (upwards).
|
|
|
Term
| Plants respond to stimuli because of unequal distribution of hormones. What is a plant's response to stimulus called? |
|
Definition
|
|
Term
Which hormone controls the way in which plants respond to light and gravity? |
|
Definition
|
|
Term
|
Definition
| Phototropism is the way in which a plant grows in response to light. When light hits one side of the plant, more auxin builds on the darker side. Excess auxin triggers more growth in these cells, making the plant bend towards the light. |
|
|
Term
| Geotropism is a term used to describe a plant's response to what? |
|
Definition
|
|
Term
| Plant growth hormones to help in horticulture and agriculture as... |
|
Definition
- weedkillers - to selectively kill weeds by affecting the way in which they grow
- rooting powders - to stimulate roots to grow more quickly on plant cuttings
|
|
|
Term
|
Definition
| Drugs are chemical substances that alter the way the body works. |
|
|
Term
| What are the three main stages in developing a new drug? |
|
Definition
- New drugs made in laboratory
- Drugs tested in laboratory for toxicity using cells, tissues and live animals
- Clinical trials involving healthy volunteers and patients to check for side-effects
|
|
|
Term
| What are statins used for? |
|
Definition
| Statins are used to lower the amount of cholesterol found in the blood. This then helps to reduce the risk of heart disease and circulatory disease. |
|
|
Term
| What is a placebo? Why is it used in drug trials? |
|
Definition
| In double blind trials, some patients are given a placebo, which does not contain the drug. neither the doctor nor patient knows who received a placebo and who received the drug until the trial is complete. This helps reduce bias in the trial. |
|
|
Term
| After thalidomide was banned, Scientists became more aware of the importance of drug trials, and henceforth trialled them more rigoursly. Why was thalidomide banned? What is thalidomide now used for? |
|
Definition
| Thalidomide was banned because when many pregnant women took the drug, the babies were born with severe limb abnormalities. Thalidomide is now used to treat leprosy. |
|
|
