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Flashcards in Unit 3 Deck (34)
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Do bacteria and viruses reproduce quickly in the body



Viruses reproduce inside cells. Describe what problem this can cause the cells

They can burst


House flies have legs covered in tiny hairs, mouthparts that secrete saliva, wings, and produce faeces. How does the House fly transmit disease to humans. Include details of how the housefly can pick up pathogens and spread them to humans

The house fly uses its wings to fly to dirty places
Pathogen stick to the Flies body
Pathogen stick to hairs on the Flies legs
Pathogens are eaten by The Fly

The fly uses its wings to travel to a human food source
The fly secretes saliva on a human food source along with pathogens that the fly ate
The housefly deposit species on to a human food source
Humans then eat the contaminated food and taking the pathogen


What type of drug can be used to control HIV

antiretroviral drugs


What system in the body does HIV attack

The immune system


What species of plant is often attacked by tmv

Tomato plants


Describe the appearance of leaves with Rose black spot and state what happens to these leaves

Purple or black spots develop on the Leaves. These leaves can then turn yellow and drop off.


A gardener notices one of her rose plants with Rose black spot. Worried about the rest of her rose plants becoming infected. Why are the other rose plants in the garden at risk.

It can spread to other plants by water or wind


Why is it necessary to vaccinate poultry

It prevents the spread of disease in poultry. It means to poultry won't be contaminated with the salmonella bacteria so they are safe for humans.


How is gonorrhea spread from person to person

Sexual contact


State two symptoms of gonorrhea in women

Pain whilst urinating. Green discharge from vagina


Name the antibiotic that used to treat people with gonorrhea



Why is penicillin no longer effective against gonorrhea

Strains of the bacteria have become resistant to it


Describe two ways the skin defend against the bodies pathogens

It acts as a barrier to stop pathogens getting in
It secretes antimicrobial substances which kill pathogens


What is injected into the body during a vaccination

A small amount of dead or weakened pathogen


How does vaccination work

It allows the body to be able to rapidly produce antibodies which defend against the pathogen


If a large proportion of population is vaccinated against the pathogen, why will the spread of the pathogen be reduced?

The large proportion of the population who have been vaccinated against the pathogen when catch the disease. This means that the people who aren't vaccinated are unlikely to catch the disease because they're a few of people able to pass it on


Why is a painkiller not able to cure bacterial infection

Because it's unable to kill pathogens


Suggest why very low doses are given at the start of clinical trials

In case the drug has harmful effects


Why clinical trials carried out using a double blind method

It allows for the placebo effect and eliminates the fact that treatment may not be working even though the patient feels it is


why is it important that scientists to peer review have no link to the original trials

To prevent them showing bias in the analysis of their results, and giving support to the results when in fact they werent valid


Explain how monoclonal antibodies can be used to treat cancer

An anticancer drug is attached to the monoclonal antibody. The monoclonal antibody targets to cancer cells and deliver the substance without killing any normal body cells near the tumour.


Give three uses of monoclonal antibodies

Pregnancy test, pectin pathogens, measuring hormone levels


Describe the process of making monoclonal antibodies

1. Inject the antigen into the mouse
2. Extract the lymphocytes from the mouse and select the correct one
3. Combine this with a tumour cell to produce a hybridoma cell that reproduces rapidly
4. Allow this hybridoma cells are produced by mitosis
5. The antibodies are then collected and purified


Name one insect that can cause damage to plants



List four signs that a plant has a disease

Stunted growth
Pictures of Decay
Malformed stems/ leaves


How can a gardener identify disease that's infected a plant

Testing kit
Gardening manual


How does cellulose cell walls protect a plant from microorganisms

Cellulose acts of physical barrier to stop pathogens entering


Give two types of chemical that plants can produce for Defence. For each type of chemical, explain how it helps the plant survive.

Antibacterial chemicals kill pathogens that could damage the plant
Poisons deter herbivores from eating the plant


State two types of mechanical adaptations that help plants protect themselves

Thorns or hairs stop animals touching and eating the plant
Drooping and curling leaves knock microorganisms off