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47 Cards in this Set
- Front
- Back
What are pathogens? |
Microorganisms that can enter both plants and animals and cause communicable diseases |
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What are bacteria? |
Small cells which reproduce rapidly and make you ill by producing toxins that damage cells and tissues |
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What are viruses? |
Reproduce rapidly (mitosis) inside cells - burst, releasing viruses, cause cell damage NOT CELLS |
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What are protists? |
Single celled eukaryotes such as parasites which live on/inside other organisms and cause damage |
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What are fungi? |
Single cells made up of hyphae which grow and penetrate human skin/surface of plants, causing disease and produce spores |
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What three ways can pathogens be spread? |
Water Air Direct contact |
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What is measles? |
Viral disease spread by air droplets which cause red rash + fever + can cause pneumonia/ encephalitis. Most people vaccinated when young. |
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What is HIV? |
A virus spread by sexual contact or exchanging bodily fluids which attacks immune cells. It causes flu-like symptoms and can be controlled with antiretroviral drugs to stop replication. |
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What is tobacco mosaic virus? |
A virus which affects plants and causes a mosaic pattern on the leaves which means photosynthesis can't carry out as well, affecting growth |
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What is rose black spot? |
A fungus that causes purple or black spots to develop on the leaves of rose plants which makes them turn yellow and drop off, affecting photosynthesis. It spreads through water or wind. |
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How can rose black spot be treated? |
Using fungicides Stripping the plant of affected leaves and destroying them |
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What is malaria? |
A disease caused by a protist which causes fever and can be fatal. |
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How is malaria spread? |
The protist is picked up by mosquitoes when they feed on an infected animal and then when they feed on another animal, they insert the protist into the animals blood vessels. |
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How can the spread of malaria be reduced? |
Preventing mosquitoes from breeding Mosquito nets Insecticides |
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What is salmonella? |
A bacteria which causes food poisoning. It causes fever, stomach cramps, vomiting and diarrhea through toxins. Most poultry is given a vaccination to prevent the spread. |
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What is gonorrhoea? |
An bacterial STD which causes pain when urinating and yellow/green discharge from the penis or vagina. |
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How is gonorrhoea treated and prevented? |
Originally with an antibiotic called penicillin but may strains have now become resistant. To prevent the spread, people are treated with antibiotics and should use condoms. |
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What four ways can the spread of disease be reduced or prevented? |
Being hygienic Destroying vectors Isolating infected individuals Vaccination |
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What five ways does the body protect itself against disease? |
Skin acts a barrier Hairs/Mucus trap pathogen particles Trachea/Bronchi secrete mucus and are lined with cilia to waft the mucus to the back of the throat Hydrochloric acid in the stomach |
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What is phagocytosis? |
When white blood cells engulf foreign cells and digest them. |
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What three ways do white blood cells protect you against disease? |
Phagocytosis Producing antibodies Producing antitoxins |
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What are vaccinations? |
Injecting yourself with small amounts of dead or inactive pathogens which carry antigens which causes your body to produce antibodies |
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What are the pros of vaccination? |
They control communicable diseases Prevent epidemics if lots are vaccinated as there are fewer carriers |
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What are the cons of vaccination? |
They don't always work Can cause side effects |
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What do antibiotics do? |
Kill bacteria causing the problem without damaging your body cells but they cannot kill viruses |
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What does bacteria mutation often cause? |
For bacteria to become resistant to an antibiotic and become hard to treat |
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What plant does aspirin come from? |
Willow |
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What plant does digitalis come from? |
Foxgloves |
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Who was Alexander Fleming? |
The discoverer of penicillin |
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What are the three stage of testing? |
Human cells and tissues Live animals Human volunteers |
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Why are drugs tested on healthy volunteers? |
To check for harmful side effects |
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Why can't be drugs used to treat whole body systems be tested on human tissue? |
As it requires an intact circulatory system |
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What is a double blind test? |
When neither the patient nor the doctor knows whether the drug is real or placebo |
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What kind of white blood cells produce antibodies? |
B-lymphocytes |
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What are monoclonal antibodies produced from? |
Lots of clones of a single white blood cell, making them all identical |
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What is a hybridoma? |
A mouse B-lymphocyte fused with a tumor cell |
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What are three ways monoclonal antibodies can be used? |
To bind to hormones and other chemicals in the blood to measure their levels To test blood samples in laboratories for pathogens To locate certain molecules on a cell |
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What is an advantage of monoclonal antibodies? |
They can target specific cells in cancer treatment reducing side effects |
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Why are monoclonal antibodies not as widely used as scientists would like? |
As they have lots of side effects such as fever and vomiting |
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What do nitrates do and what does a deficiency mean? |
Make proteins used for growth. Deficiency = stunted growth. |
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What do magnesium ions do and what does a deficiency mean? |
Make chlorophyll for photosynthesis. Deficiency = chlorosis + yellow leaves. |
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What are aphids? |
Insects which can cause huge damage to plants |
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What are six common signs of plant disease? |
Stunted growth Abnormal growth Spots on the leaves Malformed stems Patches of decay/rot Discoloration |
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How can plant diseases be identified? |
Looking up the signs in a gardening manual or website Taking the infected plant to a laboratory Using testing kits which identify pathogens using monoclonal antibodies |
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Name three physical defences of plants: |
Waxy cuticle to prevent pathogens Cell walls made from cellulose Layers of dead cells around their stems such as tree bark |
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Name two chemical plant defenses of plants: |
Antibacterial chemicals which kill bacteria Poisons |
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Name three mechanical defenses of plants: |
Thorns or hairs Leaves that droop or curl when something touches them By mimicking other plants or objects such as rocks |