B4: Infection & Response

Question 1

What is a pathogen? (5)

Answer 1

A microorganism that triggers an immune response

• bacteria
• virus
• protist
• fungi

Question 2

What is the difference between a communicable and non-communicable disease?

Answer 2

Communicable diseases, caused by pathogens, are infectious. Whereas, non- communicable diseases are not infectious.

Question 3

What are the bodies defense systems?(7)

Answer 3

• eyelashes
• nose hairs
• cilia cells
• ear wax
• mucus productions
• skin
• white blood cells

Question 4

How do lymphocytes deal with pathogens?(3)

Answer 4

• release antitoxins and antibodies which bind to specific toxins and neutralize them
• Antibodies attach to antigens, binds pathogen and destroys them or sticks them together and marks for phagocytes
• cause cell lysis

Question 5

How do phagocytes get rid of pathogens?

Answer 5

• phagocytes find the pathogen by detecting the chemicals released by it or using the marker the lymphocyte left
• phagocytes then engulf the pathogen and ingests the bacteria, breaking it down

Question 6

What are drugs ?

Answer 6

Any chemical substance the changes the body’s natural chemistry

Question 7

What is the difference between painkillers and antibiotics?

Answer 7

Pain killers alleviate the symptoms of infection but does not actually get rid of the pathogen. However, antibiotics kill the pathogen

Question 8

Why can you not use antibiotics for a virus?

Answer 8

Antibiotics work on killing the pathogens outside the cell whereas viruses reside inside the cell

Question 9

Gonorrhea (5)

Answer 9

It’s is a sexually transmitted communicable disease caused by bacteria. Symptoms : yellow discharge, pain while urinating. Can be treated by antibiotics.

Question 10

Measles(6):

Answer 10

It is a communicable disease caused by a virus. Symptoms: fever, dry cough, runny nose. Can be prevented by vaccinations.

Question 11

Malaria(6):

Answer 11

It is a communicable disease caused by a protist. Symptoms: fever, muscle pains, sweating. Treatment: antimalarials

Question 12

Coronary Heart Disease(7):

Answer 12

It is a non- communicable disease which is caused by too much fatty materials in your blood vessels. Symptoms: shortness of breath, pain in chest, nausea. Treatments: surgery, statins,stents

Question 13

Aphids(green fly)(5):

Answer 13

It is caused by a vector. Symptoms: decreased growth rate, yellow leaves, wilting, death. Treatment: they are controlled by natural predators like ladybirds and insects

Question 14

Diplocarpon rose(rose black spot)(5):

Answer 14

Symptoms: Black or purple spots on leaves , black scab- like spots.
Treatment: immediately removing infected leaves fungicides, putting manure or mulch

Question 15

Tobacco mosaic virus(5):

Answer 15

Discoloured mosaic patterns on leaves, yellow streaks or patterns on leaves
Treatment: disinfection of all tools, removal of weeds and infected plants

Question 16

Cancer is the uncontrolled division of cells, what are the two different types of tumours?(6)

Answer 16

Benign tumours are non cancerous, do not spread and are harmless unless they are in the wrong location.
Malignant tumours are cancerous, divide rapidly and will end in death if left un treated. They are difficult to remove as they spread rapidly.

Question 17

Define Metastasis.

Answer 17

When the primary tumour breaks up and travels the bloodstream to form a secondary tumour

Question 18

How are monoclonal antibodies made?

Answer 18

1. Lymphocytes from mice are combined tumour cells to form hybridoma cells
2. These cells are cloned and make the same antibody

Question 19

What are the uses of monoclonal antibodies?(4)

Answer 19

• treating cancers
• pregnancy tests
• detecting hormones
• bound to fluorescent dyes to identify molecules

Question 20

Risk factors(3):

Answer 20

• lifestyle
• age
• weight

Question 21

Define carcinogen:

Answer 21

Any substance or virus that can increase the risk factor of cancer

Question 22

Antibiotic resistance(4):

Answer 22

When there is a large group of bacteria some are antibiotic resistant

• when antibiotics have been used all cells die except the resistant ones
• this gives the resistant bacteria space and resources to multiply rapidly
• the resistant bacteria can then pass on the resistant gene making others immune to antibiotics

Question 23

What is a blind test?

Answer 23

When the patient does not know whether they are taking a drug or a placebo

Question 24

What is a double blind test?

Answer 24

When neither patient nor doctor know whether the patient is taking the drug or the placebo

Question 25

Magnesium deficiency:

Answer 25

Symptoms: yellow leaves, green veins
Explanation: magnesium is a part of the chlorophyll molecule

Question 26

Potassium deficiency:

Answer 26

Symptoms; yellow leaves, dead spots

Explanation; potassium is needed to help the plant make proteins

Question 27

Nitrate deficiency:

Answer 27

Symptoms;plant doesn’t grow properly

Explanation;it reacts with glucose to make protein which is used for growth

Question 28

Phosphate deficiency:

Answer 28

Symptoms: purple leaves
Explanation: makes chemical energy

Question 29

What causes symptoms?

Answer 29

Toxins and poisons released by the pathogen

Question 30

Why are placebos used?

Answer 30

To find out the psychological affect of the drug

Question 31

What is the next stage after double blind trials?

Answer 31

Testing on volunteers with the disease

Question 32

How do antibodies work(3):

Answer 32

• The antibody shape is specific and complimentary to the antigens on the pathogen
• The antibody binds to the toxin in the cell
• This causes cell lysis