immunology

Question 1

what is the type of a bacterium microorganism?

Answer 1

prokaryotic

Question 2

what is the type of a fungus microorganism?

Answer 2

eukaryotic

Question 3

what is the type and average size of a protist microorganism?

Answer 3

eukaryotic

Question 4

what is the type of a virus microorganism?

Answer 4

N/A

Question 5

what is a pathogen?

Answer 5

disease-causing microorganisms.

Question 6

give an example and notes of a bacteria?

Answer 6

• chlamydia, gonorrhoea, tuberculosis
• bacterial infections can be treated with antibiotics, but bacteria are becoming more resistant to them

Question 7

give an example and notes of a virus?

Answer 7

• common cold, mumps, measles, coronavirus
• viruses must infect body cells in order to replicate

Question 8

give an example of a fungi?

Answer 8

• yeast infection (thrush), toenail fungus, athletes foot.

Question 9

give an example and notes of prions?

Answer 9

• creutzfeldt-jokob disease (CJD)
• non-living, pathogenic proteins. if ingested, a mutant form or a prion can cause normal prion proteins to change shape causing damage to nervous system and may lead to death.

Question 10

give an example and notes of protists?

Answer 10

• malaria
• do not confuse the pathogen with the anopheles mosquito that carries the pathogen

Question 11

give an example and notes of parasites?

Answer 11

• toxoplasmosis
• this infection is caused by the parasitic protoctist toxoplasma gondii. many multicellular parasites can also cause infections, particularly in developing countries.

Question 12

what are the 3 ways in which causative agents enter the body?

Answer 12

direct, airborne and indirect transmission.

Question 13

what is direct transmission?

Answer 13

physical contact with an infected person
e.g. skin-skin contact or contaminated surfaces (such as sharing needles or door handles)

Question 14

what is airborne transmission?

Answer 14

the pathogen is carried by dust or droplets in the air (they can remain for many hours)
e.g. covid-19

Question 15

what is indirect transmission?

Answer 15

occurs when infected food or water are ingested, or through vehicle emissions
e.g. food poisoning or not washing hands properly

Question 16

how do diseases spread among populations?

Answer 16

• inadequate sanitation
• inadequate sewage disposal
• large populations leading to no social distancing
• inadequate healthcare infrastructure
• lack of accessible health promotion information

Question 17

what is an antigen?

Answer 17

a substance found on the surface e of all body cells.
it has a specific spike shape and stimulates immune response.

Question 18

what is an antibody?

Answer 18

a blood protein produced in response to antigens.
they bind specifically to an antigen.

Question 19

what is phagocytosis?

Answer 19

a type of white blood cell which engulfs and digests pathogens.

Question 20

what is inflammation?

Answer 20

• response to injury or infection,
• increased blood flow in capillaries,
• capillaries begin to leak more, allowing fluid to enter tissue resulting in swelling,
• phagocytes leave blood & enter tissue where they engulf foreign materials.

Question 21

what is a lymphocyte?

Answer 21

a small white blood cell.

Question 22

what are physical barriers?

Answer 22

• first line // keeps pathogens out, skins external barrier
• mucus membrane // lines gut & airways. goblet cells produce thick mucus trapping bacteria.

Question 23

what are chemical barriers?

Answer 23

• antimicrobial proteins // helps to destroy pathogens & stimulation of immune system
• lysosome // enzyme hydrolyse bonds in bacteria & bacteria swell and burst.

Question 24

what are T and B cells activated by?

Answer 24

foreign antigens on pathogens or other foreign cells.

Question 25

what are the T helper cells surface receptor?

Answer 25

CD4

Question 26

what are the B cells surface receptor?

Answer 26

BCR

Question 27

what are the T killer cells surface receptor?

Answer 27

TCR

Question 28

what happens when a T helper cells meets an antigen presenting cell (pathogen)

Answer 28

if antigen is complimentary to CD4, T helper cell divide by mitosis to form a clone and memory cell. T helper cells then activate killer cells.

Question 29

what happens when a T killer cells meets an antigen presenting cell (pathogen)

Answer 29

if T killer cells encounter a pathogen and is complementary, is divides via mitosis and clone itself to bind to other infected cells and destroy them.

Question 30

what happens when a B cells meets an antigen presenting cell (pathogen)

Answer 30

if B cell is complimentary to BCR, antigen binds to BCR and engulfs it. B cell takes antigens from pathogen and presents it on outside and pretends to be the pathogen. B cell is activated by cytokines for T cells and produces antibodies.

Question 31

how does the specific immune system work?

Answer 31

- T helper cell is activated and then activates B cells - B cell either then produces antibodies or activates T killer cells to destroy the pathogen

Question 32

what is a cell-mediated response?

Answer 32

T killer cells destroy pathogens by destroying infected body cells. antibodies are NOT involved

Question 33

what is an antibody-mediated response?

Answer 33

B cells produce antibodies and destroy pathogens. some antibodies are known as antitoxins, they bind to and neutralise toxins produced by pathogens

Question 34

what is a secondary immune response?

Answer 34

activation of T and B cells leads to a production of memory cells. they stay in body and if reinfected by same pathogen, antibodies are produced more rapidly in larger quantities

Question 35

how do vaccines work?

Answer 35

they stimulate a primary immune response which produces T and B memory cells and in the event on an infection, secondary immune response is triggered