Biology Paper 1 Flashcards
(112 cards)
1
Q
What are communicable diseases?
A
Diseases that can be spread between individuals, both plants and animals.
2
Q
What are non-communicable diseases?
A
Diseases that cannot be transmitted between individuals.
3
Q
What are 2 examples of non-communicable diseases?
A
Arthritis and coronary heart disease.
4
Q
What are the 3 ways communicable diseases be spread?
A
By droplet infection (through the air), through the water and via direct contact (touching).
5
Q
What are the 4 methods to reducing the spread of diseases?
A
-Simple hygiene methods (hand washing)
-Destroying vectors
-Isolation of infected individuals
-Vaccinating the population
6
Q
What is a vector? Give an example
A
A vector is an organism, which transfers and transmits the pathogen from one organism to another, e.g. mosquitos and their breeding grounds.
7
Q
What are some of the factors that can affect the chance of being ill?
A
-Diet
-Stress
-Age
8
Q
What can communicable diseases be caused by?
A
Pathogens
9
Q
What are pathogens?
A
Disease causing microorganisms.
10
Q
What are the 4 types of pathogens?
A
-Bacteria
-Viruses
-Protists
-Fungi
11
Q
What environment do fungi thrive in?
A
A warm and moist environment.
12
Q
What are 2 examples of fungal diseases?
A
Athletes foot and fungal endocarditis.
13
Q
What are protists?
A
Microscopic and unicellular.
14
Q
What is an example of a protist disease?
A
Malaria
15
Q
How do viruses make you ill?
A
They invade the body cells. They then continue to live and reproduce inside the cells until the cell bursts, which damages and destroys them. This can either create direct symptoms or symptoms as a result of the immune system fighting of the infection.
16
Q
What are 2 examples of viral diseases?
A
HIV and measles.
17
Q
Are viruses dead or alive? Why?
A
Dead, this is because they are unable to reproduce on their own.
18
Q
How can bacteria make you ill?
A
They divide by binary fission and produce toxins, which make you ill. They can also damage the body cells.
19
Q
What are 2 examples of bacterial diseases?
A
Salmonella and gonorrhoea.
20
Q
Are bacterial pathogens eukaryotic or prokaryotic?
A
Prokaryotic
21
Q
Which are smaller, bacteria or viruses?
A
Viruses
22
Q
What are the 2 ways to culture microorganisms?
A
In a lab on an agar plate and in a nutrient broth solution.
23
Q
What is a large group of bacteria called?
A
A colony
24
Q
What can scientists discover from culturing microorganisms?
A
What microorganisms need to survive and what methods can be used to kill them,
25
What nutrients are in the agar plate to allow the bacteria to survive?
Nitrogen (to make proteins), carbohydrates (as an energy source) and other various minerals.
26
What is the process for the culturing microorganisms required practical?
1) Set up a bunsen burner and light it, making sure it is on a blue flame. Put your inoculating loop in the flame for about 1 second, to sterilise the loop.
2) Leave the bunsen burner on for the rest of the practical, this creates an updraft and moves the bacteria upwards and away from the agar plate.
3) Dip the inoculating loop into the bacteria being used and partially removed the lid from the petri dish containing agar, but make sure not to fully take off the lid. This is to limit the chances of bacteria entering the dish.
4) Spread the bacteria in a zig zag motion across the agar to get full coverage. When not spreading close the lid (prevent bacteria entering). Turn the petri dish 90 degrees and repeat, so that the bacteria is evenly distributed.
5) Put the lid back on the petri dish and put 2 pieces of selotape at opposite sides of the lid to secure, making sure oxygen can get in, so the bacteria is able to survive and grow.
6) Label it with your name and date and store it upside down in an incubator at 25 degrees. This is so the condensation doesn't fall onto the agar surface. It is also only at 25 degrees, so that any bacteria grown cannot be a harmful pathogen to humans, as we have a body temperature of 37 degrees.
27
What temperature do hospitals grow bacteria at?
37 degrees
28
What is the equation for bacterial growth?
Bacteria at the end of growth = Bacteria at the beginning of growth x 2 to the power of the number of divisions
29
How do you work out the number of divisions?
Divide 60 by the time it takes for the bacteria to divide and multiply this by the number of hours it's dividing for.
30
Are fungi eukaryotic of prokaryotic cells?
Eukaryotic
31
What do fungi produce and why?
Spores for reproduction.
31
What are 4 types of fungi?
Mushrooms, toad stalls, moulds and yeast.
32
What do fungi digest?
Organic matter.
33
Do fungi photosynthesise?
No
34
Are plants or animals more affected by fungi?
Plants
35
Are protists eukaryotic or prokaryotic?
Eukaryotic
36
What type of pathogen is measles?
A virus
37
How is measles spread?
Droplet infection
38
What are the symptoms of measles?
Fever and red skin rash.
39
What are the potential complications of measles?
Blindness, brain damage and death.
40
How can measles be prevented?
MMR vaccine
41
What is the treatment for measles?
None, but isolation to stop the spread and vaccination to limit the number of cases.
42
What type of pathogen is HIV/AIDs?
Virus
43
How can HIV be spread?
Unprotected sexual contact, exchange of bodily fluids (blood) and breast milk.
44
What are the symptoms of HIV?
Initially flu like symptoms. Then the virus attacks the immune cells and remains hidden within the immune system damaging it. This prevents the person dealing with infections and can be fatal.
45
What are the potential complications of HIV?
It can reduce the effectiveness of the immune system, which means you are more likely to get infections.
46
How can you prevent the spread of HIV?
Use condoms and don't share needles.
47
What is the treatment for HIV?
There isn't a cure but using antiretroviral medication can increase life expectancy.
48
Does HIV automatically develop into AIDs?
No
49
What affects the development of HIV into AIDs?
Nutrition, health and antiretroviral drugs.
50
What type of pathogen is athletes foot?
Fungal
51
What are the symptoms of athletes foot?
A scaly rash, which can cause itching and burning.
52
What causes athletes foot?
Sweaty feet in tight fitting shoes.
53
What is the treatment for athletes foot?
Antifungal medication.
54
What type of pathogen in fungal endocarditis?
Fungal
55
What are the symptoms of fungal endocarditis?
Fevers, sweats, fatigue, changing heart murmur and death.
56
What is the cause of fungal endocarditis?
A fungal, via the bloodstream, is able to reach the heart.
57
What is the treatment of fungal endocarditis?
Possible replacement of heart valves and antifungal therapy.
58
What are the risk factors for getting fungal endocarditis?
Being an intravenous drug user, having a history of heart surgery, having HIV and having a central venous catheter fitted.
59
What type of pathogen is salmonella?
Bacteria
60
What causes the spread of salmonella?
Eating undercooked or contaminated chicken or egg products.
61
What are the symptoms of salmonella?
Cramps, diarrhoea and vomiting.
62
When do symptoms of salmonella begin?
8-72 hours after eating.
63
What are the potential complications of salmonella?
The young and elderly are at risk of death due to dehydration. The malnourished are also at risk of death.
64
How can salmonella be prevented?
In the UK, poultry are vaccinated. You also must ensure a high level of food hygiene as well as making sure food is fully cooked.
65
What are the treatments of salmonella?
No antibiotics are given but you are advised to rest.
66
What type of pathogen is gonorrhoea?
Bacteria
67
How is gonorrhoea spread?
Unprotected sexual contact,
68
What are the symptoms of gonorrhoea?
Thick yellow/green discharge from the vagina/penis. Pain when urinating. However sometime there are no symptoms (10% in men and 50% in women).
69
What are the potential complications of gonorrhoea?
Long term pelvic pain, infertility and ectopic pregnancy. In addition babies born to infected mothers can have severe eye infections or be blind.
70
How can gonorrhoea be prevented?
Using a barrier method (contraception), reduce the number of sexual partners and have sexual health checks.
71
How can gonorrhoea be treated?
Given antibiotics, however some strains are becoming resistant to antibiotics.
72
What type of pathogen in malaria?
Protist
73
How is malaria spread?
Female mosquitos need to have 2 meals of blood a day before laying eggs, so when they bite someone, the protist goes into the bloodstream.
74
What are the symptoms of malaria?
Fevers and shaking occur. Slowly become weaker and death. As well as liver and red blood cells being damaged.
75
What are the potential complications of malaria?
Liver disease and fluid in the lungs
76
How is malaria prevented?
Use insecticide-impregnated insect nets, to prevent humans being bitten. Using insecticides to kill mosquitoes. Preventing the breeding of mosquitoes by removing their breeding habitats like standing water. Finally, by providing travellers with antimalarial drugs which kill the parasites if they get bitten (these are taken both before, during and after travelling).
77
How can malaria be treated?
If diagnosed quickly it can be treated, however treatment isn't readily available in countries with malaria.
78
What are 5 ways the body prevents infection from the 1st line of defence?
Skin
Nose
Trachea and Bronchi
Stomach
Eyes
79
How does the skin prevent infections?
Provides a protective barrier that prevents pathogens entering the body. It secretes oil. It also forms scabs when cut or bleeding.
80
How does the nose prevent infections?
Contains tiny hairs that trap pathogens?
81
How does the trachea and bronchi prevent infections?
Goblet cells produce mucus. The trachea contains ciliated epithelial cells which move the mucus up to the nose. The mucus then traps the pathogens.
82
How does the stomach prevent infections?
It contains hydrochloric acid, which destroys pathogens that are eaten.
83
How do the eyes prevent infection?
By producing tears.
84
What are the 3 ways the body prevents infection from the 2nd line of defence?
All using white blood cells:
Phagocytosis
Antibody production
Antitoxin production
85
Where are white blood cells made?
Bone marrow
86
What is the process of phagocytosis?
White blood cell ingest pathogens, digesting them with enzymes so they cannot make you ill. Once the phagocytes have ingested as many pathogens as they can, they die. Their dead cells form around a cut as puss.
87
What is the process of antibody production?
White blood cells called lymphocytes produce antibodies. These target specific and stick to the specific molecules on their surface called antigens. This then prevents them spreading and targets them for destruction by the immune system. Antibodies are specific to a particular pathogen and can be rapidly made again should reinfection happen.
88
What is the process for antitoxin production?
White blood cells produce antitoxins. These bind to toxins made by bacteria and prevent them harming your cells.
89
What happens when antibodies and antitoxins are produced?
Memory cells are formed.
90
What do memory cells allow to happen?
A quick response to the same pathogen again, and allows you to become more resistant to specific pathogens.
91
Can a vaccination cause side effects?
Yes, but they are usually rare and mild.
92
Can everyone be vaccinated?
Not always, sometimes the elderly and those with immune system deficiencies are too weak to be vaccinated.
93
Why do we attempt to gain herd immunity?
To protect those who are unable to be vaccinated.
94
What is heard immunity?
This is where the majority of the population is vaccinated, preventing the spread of disease as there aren't enough hosts to carry the disease to the vulnerable people.
95
What is the process of how vaccination works?
1) A dead or weakened pathogen is injected, which means it can't make us ill.
2) White blood cells detect the pathogen as the antigen is different.
3) The white blood cells produce antibodies to destroy the pathogen. This is a slow process.
4) The white blood cells cause memory cells to form, which remember which antibody to make.
5) If infected with the pathogen again in the future, memory cells cause antibodies to be produced quickly. Therefore, they don't even realise they are infected.
6) The patient is now immune.
96
What are antibiotics used to cure?
Bacterial diseases
97
Why aren't antibiotics able to completely eradicate disease? 2 reasons.
Bacterial pathogens aren't the only type of pathogen.
Some strains of bacteria are becoming antibiotic resistant.
98
What are 2 examples of antibiotics?
Penicillin and amoxicillin.
99
How do antibiotics cure us of bacterial diseases?
They work by killing the bacteria that makes us ill, this is done by destroying the bacteria cells, by causing damage to the cell wall, but they don't damage the human cells
100
Why aren't antibiotics able to cure viral diseases?
Viruses invade and hide in our cells and antibiotics don't harm human cells.
101
True or false? Antibiotics can be injected directly into the blood.
True
102
What are 2 examples of antiseptics and disinfectants?
Dettol and JIF
103
Why can't antiseptics and disinfectants be used inside the body?
They are too dangerous and would also kill us
104
What are antiseptics and disinfectants used for?
To kill bacteria outside the body
105
What are 2 examples of painkillers?
Paracetamol and aspirin
106
What are painkillers used for?
To relieve pain but don't combat the pathogen
107
What is antibiotic resistance?
Evolution or mutation of bacteria
108
What 3 guidelines should be followed to reduce the spread of antibiotic resistance?
Doctors should only prescribe antibiotics for serious bacterial infections (not viral infections)
Patients must finish all the antibiotics that they are prescribed by a doctor and not stop just because they fee better
The agricultural use of antibiotics should be reduced and kept to a minimum
109
What is the disadvantage of how antibiotics are produced?
It is a long and costly process, so can't keep up with new antibiotic resistant strains
110
How do bacteria become antibiotic resistant?
A bunch of bacteria including a resistant variant get bathed in antibiotics.
Most of the normal bacteria die.
The resistant bacteria multiply and become more common.
Eventually the entire infection evolves into a resistant strain.
111
