P1: Infection And Response Flashcards
(86 cards)
1
Q
What are the four main types of pathogen?
A
Virus, bacteria, fungi, protist.
1
Q
What is a pathogen?
A
A microorganism that causes disease.
2
Q
What do viruses do inside cells?
A
Live and reproduce, causing cell damage.
2
Q
What are the different methods of transmission of a disease?
A
Direct contact, water, air, unhygienic food preparation and vector.
3
Q
What is the name for a disease caused by a pathogen?
A
Communicable disease.
4
Q
What is the name of an infected plant or animal?
A
A host.
5
Q
What do bacteria do?
A
Produce toxins that damage tissues and make us feel ill.
6
Q
What type of disease is HIV/AIDS?
A
Virus
7
Q
How is HIV/AIDS transmitted?
A
By exchange of bodily fluids.
8
Q
What are the symptoms of HIV/AIDS?
A
Initially, mild flu-like symptoms. Eventually attacks the immune system.
9
Q
What is the treatment for HIV/AIDS?
A
No vaccine currently, but infected people are given antiviral drugs which can slow the development of AIDS.
10
Q
What type of disease is tobacco mosaic disease?
A
Virus
11
Q
How is Tobacco Mosaic Virus transmitted?
A
By contact between plants, or through the hands of farmers
12
Q
What is the cure for Tobacco Mosaic Virus?
A
No cure. Some plants have developed resistance, but otherwise farmers have to try and reduce the infection.
13
Q
What does Tobacco Mosaic Virus do to the plant?
A
Infects the chloroplasts and changes the colour from green to yellow/white in a mosaic pattern. Reduces the plant’s ability to photosynthesise and grow properly.
14
Q
What type of disease is Measles?
A
Viral
15
Q
How is Measles transmitted?
A
Through the air in tiny droplets after an infected person sneezes.
16
Q
What are the symptoms of Measles?
A
Fever and skin rash. In rare cases it can cause blindness.
17
Q
What is the treatment for Measles?
A
Children are given vaccines against measles.
18
Q
What type of disease is Gonorrhoea?
A
Bacterial
19
Q
How is Gonorrhoea transmitted?
A
Sexual contact with the genitalia, anus or mouth of an infected partner.
20
Q
What are the symptoms of Gonorrhoea?
A
-Burning pain on urination
-Thick yellow or green discharge
-Infertility
21
Q
What is the treatment for Gonorrhoea?
A
Antibiotics. However, many are no longer as effective as they used to be because the bacteria is evolving to become resistant.
22
Q
What type of disease is Salmonella?
A
Bacteria
23
How is Salmonella transmitted?
By eating food that contains the bacteria. Food can become contaminated with it if it is prepared in unhygienic conditions.
24
What are the symptoms of Salmonella?
Abdominal cramps, vomiting, diarrhoea, fever.
25
How is Salmonella treated?
Antibiotics, however preventative measures are also taken. All poultry are vaccinated against it in the UK. Cooking food thoroughly after preparing it in hygienic conditions is the best way to avoid illness.
26
What type of disease is Malaria?
Protist
27
What are the symptoms of Malaria?
Fever, sweats and chills, headaches, vomiting and diarrhoea.
27
How is Malaria spread?
Plasmodium protist enters the mosquito (the vector), from the bloodstream of an infected person. The mosquito lands on another human and sucks blood from them, while the plasmodium enter the bloodstream. The human is the host.
28
How is Malaria treated?
There is no vaccination for it. Infection can only be prevented by sleeping under mosquito nets and wearing insect repellent. Antimalarial drugs can also be taken which treat the symptoms.
28
What type of disease is Athlete’s Foot?
Fungal.
29
How is Athlete’s Foot treated?
Antifungal medication.
29
What are the symptoms of athlete’s foot?
Dry, red and flaky or white, wet and cracked skin.
30
What type of disease is Rose Black Spot?
Fungal
30
How is Athlete’s Foot transmitted?
By touching infected skin or surfaces that have been previously contaminated. (For example, swimming pools changing rooms, gyms).
31
What are the symptoms of Rose Black Spot? Explain the effects, too.
Black or purple spots on the leaves. Red of the leaves turn yellow and drop off. This reduces the plant’s ability to photosynthesise and reduces growth.
32
How is Rose Black Spot transmitted?
In air or water, or direct contact.
33
How can Rose Black Spot be treated?
Using fungicides and by removing and destroying infected leaves.
34
What are the defence systems in the eyes?
Eyes produce tears which contain enzymes that act as chemical barriers.
34
What are the defence systems in the nose?
Contains internal hairs which act as a physical barrier. Cells produce mucus which trap the pathogens before they can enter the lungs.
35
What are the defence systems in the skin?
Covers all of your body to prevent infection. Forms scabs, acting as a physical barrier
35
What are the two key types of white blood cells?
Phagocytes and Lymphocytes.
36
What are the defence systems in the stomach?
Contains hydrochloric acid which is strong enough to kill any pathogens that have been consumed in food or water, or swallowed in mucus.
36
What are the defence systems in the trachea and bronchi?
Trachea is lined with cells that have hairs called cilia which move mucus and pathogens upwards towards the throat to be swallowed in your stomach.
Bronchi are lined with cells that create mucus and trap pathogens to protect the lungs.
37
What do phagocytes do?
Surround any pathogens in the blood and engulf them. They are attracted to and bind to pathogens. Enzymes within the phagocyte break down the pathogen.
38
What do lymphocytes do?
They recognise proteins on the surface of pathogens called antigens. These detect that the pathogens are foreign and produce antibodies. The antibodies make the pathogens stick together and make it easier for phagocytes to engulf.
39
What do some pathogens produce and what do lymphocytes produce in response?
Pathogens produce toxins, and lymphocytes produce antitoxins to neutralise them.
40
Describe how a vaccine works (Long answer)
-A vaccine is a dead or weakened version of the virus
-A syringe injects this
-Lymphocytes recognise the antigens as being foreign, and release complementary antibodies to the specific antigen.
-The antigens and antibodies attach and clump the pathogens together
-Phagocytes engulf the pathogens, phagocytosis occurs.
-Lymphocytes remember how to create the exact antibody, so if the virus enters the body again, the lymphocytes can quickly produce the correct antibodies and phagocytosis can occur quickly without the human experiencing symptoms.
41
What is herd immunity?
The protection given to a population against an outbreak of a specific disease when a very high percentage of the population have been vaccinated against it.
42
What are painkillers?
Chemicals that relieve the symptoms but do not kill the pathogens. Examples include paracetamol and aspirin.
42
43
What are antibiotics?
Substances that slow down or stop the growth of bacteria, NOT viruses.
44
How do viral diseases work?
Virus enters the cell, and rapidly divides inside, causing the cell to explode and begins to infect other cells.
45
State some of the reasons why antibiotics are becoming less effective.
Overuse of them, failing to complete the fully prescribed course by a doctor, use of antibiotics in farming.
46
How can we reduce antibiotic resistance?
Only take antibiotics when necessary
Treat specific bacteria with specific antibiotics,
High hospital hygiene levels,
Patients who are infected with antibiotic resistant strains of bacteria should be isolated from other patients.
46
What are drugs tested for in drug trials?
Toxicity, efficacy, and dosage.
47
Describe the 3 stages of testing drugs.
1- The drugs are testing using computer models and skin cells in a laboratory. Allows efficacy and possible side effects to be tested
2- Drugs are tested on animals. Monitoring for any side-effects
3- Drugs are tested in human clinical trials. First, human volunteers without the illness to check that they are safe. Then, on people wit the illness to ensure that they are safe and work. Low dosages used initially, and then dosage increases until optimal dosage is identified.
48
What is a placebo drug?
A physical pill that doesn’t contain any medication, but looks identical to the real thing.
49
What is a double blind trial?
A trial whereby neither the doctors nor the patients know which drugs are the placebos or the real drug.
50
What are monoclonal antibodies?
Identical copies of an antibody produced by fusing a spleen cell with a cancerous white blood cell which can be designed to bind to many different substances.
50
Where does aspirin originate from?
Willow trees.
51
Where does digitalis originate from?
Foxgloves
52
Who discovered Penicillin?
Alexander Fleming from the Penicillium Notatum mould.
53
How is a monoclonal antibody made?
-An **antigen** is injected into the mouse.
-The mouse produces **lymphocytes** which produce **antibodies** specific to the antigen.
-**Spleen cells** which produce the **lymphocytes** are removed during a small operation.
-**Spleen cells** are fused with **cancerous white blood cells** to form **hybridoma** cells
-The hybridoma cells divide and those that produce **antibodies** are separated.
-**Antibodies** are collected. These are monoclonal antibodies.
54
What are the uses of monoclonal antibodies?
Pregnancy test kits, cancer diagnosis and treatment, other diagnostic uses.
55
How are Monoclonal Antibodies used to treat cancer?
MABs can carry drugs that have been attached to them and deliver them to the tumour
MABs can encourage your immune system to attack the cancer cells directly.
56
What are the benefits of Monoclonal Antibodies?
-Have many purposes
-Can be produced quickly despite the fact that it can be time consuming when they are made for the first time
56
How do monoclonal antibodies work in pregnancy test kits?
-Monoclonal antibodies have been designed to bind with a hormone only found in the urine of pregnant women.
-MABs are attached to the end of a pregnancy test stick onto which a woman urinates.
-If she is pregnant, the hormone with bind to the MABs on the test stick, which will cause a change in colour or pattern to indicate pregnancy.
57
How are monoclonal antibodies used to diagnose cancer?
Cancerous cells have antigens, and MABs can be designed to bind specifically with these antigens. When injected into a person’s body, the MABs will bind with these cells and clump them together, making it easier to identify a cancerous tumour.
58
How are aphids damaging to plants?
Aphids are an insect that can infest plants, and feed upon their phloem and sap.
58
What are the limitations of Monoclonal Antibodies?
-Interactions of MABs in the human body has resulted in unwanted side effects.
-Expensive to produce
-People disagree with the usage of animals to produce MABs
59
What are deficiency diseases?
Diseases caused by a lack of essential vitamins or mineral ions.
59
How do gardeners reduce the aphid population?
By cultivating ladybirds, which eat the aphids.
60
What happens to a plant if it has a nitrate deficiency?
Without nitrates, the plant cannot create proteins, which reduces chlorophyll levels and reduces their ability to photosynthesise and grow properly.
61
What is magnesium used for in a plant?
To make chlorophyll
61
What is nitrate used for in a plant?
Nitrates are used as a supply of nitrogen, which is needed to make proteins for healthy growth.
62
How can ion deficiencies in plants be resolved?
By incorporating fertilisers into the soil the plants grow in.
63
What happens to a plant if there is a Magnesium ion deficiency?
The plant is limited in its photosynthetic ability and plant growth is compromised.
64
How can you investigate how plants suffer from deficiency diseases?
Sow barley seeds onto cotton wool on different Petri dishes, using different solutions (some with deficiencies, some without), and record the total dry mass of the barley seeds in each petri dish after a select amount of days.
65
What are the chemical defences of plants?
Some plants produce antibacterial chemicals
Other plants have developed poisons to prevent themselves from being eaten.
65
What are the physical defences of plants?
Many are covered in thick bark.
Each plant cell has a cellulose cell wall to act as a barrier against infection.
Leaves are covered with a waxy cuticle which stops cells from becoming infected.
66
Why can’t antibiotics be used to treat viruses?
Because viruses live within cells, and to get into them antibiotics would have to damage the cells
66
List some of the mechanical plant defences.
Thorns and hairs, drooping leaves, mimicry.
67
Explain how a vaccine for HIV could work to prevent a person developing an HIV infection.
-Inactive HIV is injected into bloodstream
-White blood cells produce antibodies
-If infected with HIV, the specific antibodies are produced quickly
-The antibodies destroy the HIV.
68
Explain how a monoclonal antibody for HIV could be produced.
-HIV injected into mouse
-Extract mouse lymphocytes that make a specific antibody to HIV
-Lymphocytes are combined with a tumour cell to create a hybridoma
-Hybridoma cloned to create many cells that produce the antibody.
