B2-Health And Disease

Question 1

What’s the relationship between health and disease?

Question 2

What are the 2 types of diseases

Answer 2

-Communicable(can spread between organisms)
-Non-communicable(cannot spread between organisms)

Question 3

What are the 4 types of pathogens?

Answer 3

-Bacteria
-Viruses
-Protists
-Fungi

Question 4

How can communicable diseases spread in animals and plants?

Answer 4

-Water
-Air
-Surfaces
-Body fluids
-Animal Vectors
-Soil
-Vectors

Question 5

What is Influenza (viral)?

Answer 5

-A virus that is spread through the air

Question 6

What is HIV (viral)?

Answer 6

-Spread by exchanging bodily fluids and sexual contact.
-Symptoms are fever, tiredness, aches. Later you might feel better but the virus is doing more damage to the immune system.
-Because the immune system is so weak, you start to catch unusual infections or get cancer. At this point, we say the person has developed AIDS which is a disease where the person’s immune system cant cope anymore.
-You can take Antiretroviral which prevents the disease from replicating and needs to be taken early in disease.

Question 7

What is Salmonella (bacterial)?

Answer 7

-A bacteria found is some foods(e.g. raw meat)
-Happens when food is kept too long or not cooked properly
-Causes food poisoning
-Symptoms include vomiting and diarrhoea

Question 8

What is Athlete’s foot (fungal)?

Answer 8

-A fungal disease spread by touching the same surface as an infected person.
-makes skin on feet itch and flake off.

Question 9

What is malaria (protist)?

Answer 9

-A protist thats spread through animal vectors.
It infects by inserting protist into animal’s blood vessel.
-causes repeated fevers(can be fatal).

Question 10

What is Tobacco Mosaic Virus (viral)?

Answer 10

-Affects Tobacco and Tomato plants.
-Called Mosaic because it has discoloured patches on the leaves making a Mosaic pattern to form.
-Photosynthesis can’t take place on the discoloured patches so the plant won’t be able produce enough sugars for proper growth.

Question 10

What is Ash Dieback (fungal)?

Answer 10

-Causes ash trees to loose leaves, develop brown patches on their bark, and eventually die.
-Caused by spores carried by the wind, as well as direct or indirect contact with contaminated plants.

Question 11

What is Crown Gall Disease (bacterial)?

Answer 11

-A bacteria that lives freely in soil and roots of plants.
-If they enter a plant, they cause tumours that damage plant tissue.
-The plant then becomes weaker or even die.

Question 12

What are three Non-specific defence systems of the human body against pathogens?

Answer 12

-Physical Defences= They act as a physical barrier to pathogens.
-Chemical Defences= They involve chemicals which kills pathogens.
-Microbial Defences= They involve other micro-organisms.

Question 13

What are physical defence systems?

Answer 13

-Whole Respiratory Tract is lined with mucus(muscus traps particles that can have pathogens).
-Skin(if theres a wound, pathogens can enter).
-Platelets clump togethor to repair the wound.

Question 14

What are chemical defence systems?

Answer 14

-Eyes produce lysozyme(in tears) which breaks down bacteria.
-Saliva has molecules which kills pathogens that enter the mouth.
-Stomach produces hydrochloric acid(which kills pathogens).

Question 15

What are Microbial Defences?

Answer 15

-Some pathogens make it past the saliva, acid in the stomach and enter the gut.
- There, they need to compete with bacteria which naturally lives in the gut (intestines) to survive.

Question 16

What are platelets?

Answer 16

-Tiny fragments of cells(with no nucleus) that help to blood to clot at wound sites.

Question 17

How are platelets adapted to their function?

Answer 17

-Platelets have proteins on their surface which help bind to the site of the wound.

Question 18

What’s the role of the immune system when defending against diseases?

Answer 18

-Pathogen is detected and surrounded bythe phagocyte. The pathogen is engulfed. A vessicle containing enzymes fuses with the pathogen. The pathogen is then digested by the enzymes.
-Lymphocytes produce antibodies that are specific to the antigen. If a person is infected with the same pathogen, memory cells will trigger a rapid response.

Question 19

How are white blood cell’s adapted to their function in the blood?

Answer 19

-Phagocytes have receptors that bind to the antigen on pathogens.
-WBC’s can produce anti-toxins that bind and counteract toxins, so cells aren’t damaged.
-Antibodies are proteins that bind to antigens on the pathogen and act as a signal to tell our WBC’s to come and destroy them.

Question 20

How can the spread of communicable diseases be reduced in animals?

Answer 20

-Vaccination
-Sterilising wounds
-Isolating infected individuals
-Being hygienic(e.g.washing hands)
-Contraception(to reduce risk of HIV)

Question 21

How can the spread of communicable diseases be reduced in plants?

Answer 21

-Destroying infected plants
-Crop Rotation
-Biological control(using another organism to control a pest/pathogen)

Question 22

What is a vaccine?

Answer 22

-A vaccine contains dead or weakened pathogens so that they can’t cause a disease.

Question 23

What are the pros of vaccines?

Answer 23

-Controls common diseases(e.g.whooping cough)
-Prevents outbreaks that could kill a lot of people.

Question 24

What are the cons of vaccines?

Answer 24

-Vaccines don’t always work
-Some people may have a bad reaction to vaccines (e.g. swelling and in some rare cases seizures or fevers)

Question 25

How can lifesyle affect the risk of developing non-communicable diseases?

Answer 25

-Obesity is caused by the poor lifestyle choices and is a risk factor for diabetes and heart attacks.

Question 26

How can the environment affect the risk of developing non-communicable diseases?

Answer 26

-Exposure to air pollution and smoking are both risk factors fror diseases like lung cancer.
-Lots of risk factors can influence one particular disease (e.g. diet, obesity and a lack of exercise). They all contribute to cardiovascular disease(CVD).

Question 26

How do non-communicable disease have a global effect?

Answer 26

-A higher income associates with a lack of exercise and higher alcohol consumption.
-Smoking-related deaths are more common in poorer countries.

Question 27

How do non-communicable disease have a national effect?

Answer 27

-Deprived areas more likely to smoke, poor diet, not exercise than people that are financially stable.
-Means heart disease, obesity, type 2 diabetes are more higher in those areas.
-deprived areas more likely to suffer from alcohol-related disorders.

Question 27

How do non-communicable disease have a local effect?

Answer 27

-Individual lifestyle choice such as choosing to smoke, drink and have a poor diet increases the risk of non-communicable diseases.

Question 28

Exlpain the link between different types of diseases.

Answer 28

-Having a specific disease can increase or decrease the risk of devloping or contracting another disease.

Question 29

How is medicine used to treat diseases?

Answer 29

-Medicine can relieve symptoms(e.g. paracetamol) or treat the disease(e.g. antibiotics).
-Antibiotics can kill or prevent the growth of bacteria.
-Some bacteria can become antibiotic resistant, making the medicine ineffective.

Question 30

How can cardiovascular disease be treated?

Answer 30

-Healthy lifestyle= changes to your lifestyle can reduce the risk of developing CVD
-Medicine= Medicine(e.g. Statins) can reduce the effect of CVD, certain medicine has side effects.
-Surgical Procedure= If a blood vessel is blocked, then a stent can be placed to keep them open, or in some cases the whole heart can be replaced by a donor heart.

Question 31

How is new potential medicine discovered?

Answer 31

-Studyng the genome and proteins of the pathogen can help find targets for new medicine.
-Chemicals are screened for their ability to affect the target.
-Chemicals that are suitable are modified for further tests.

Question 32

What is preclinical testing?

Answer 32

-Drugs are first tested on cultured human cells (grown in a lab). However you cant use human cells to test drugs that affect whole/multiple body stystems.
-Next, drug is tested on live animals. To see if drug is effective (effect your looking for) and see if it is safe.

Question 33

What is clincal testing?

Answer 33

-When the drug passes the tests on animals, it is then tested on human volunteers.
-The drug must be tested on healthy volunteers first to ensure no side effects. Then it can be tested on humans with the disease.
-Placebo’s can be used to make the person feel better eventhough it doesn’t do anything.