Human Defense System

Question 1

What is a pathogen?

Answer 1

A disease causing organism

Question 2

What is an antigen?

Answer 2

A substance (protein) on the surface of a pathogen, causes lymphocytes (white blood cells) to produce antibodies

Question 3

What is an antibody?

Answer 3

Proteins produced by lymphocytes in response to an antigen

Question 4

What is an antibiotic

Answer 4

Chemical produced by micro organisms (bacteria) to kill other bacteria (pathogens)

Question 5

Do antibiotics work on viruses?

Answer 5

No

Question 6

What is immunity?

Answer 6

The ability to resist disease

Question 7

What is a vaccine?

Answer 7

A substance introduced into the body to induce an antibody response leading to immunity

Question 8

What is vaccination?

Answer 8

The introduction of a non disease causing dose of a microbe to start an active immune response

Question 9

What is asepsis?

Answer 9

Excluding as many micro organisms/ microbes as possible

Question 10

What are aseptic techniques?

Answer 10

Techniques used to eradicate microbes e.g. flaming, alcohol

Question 11

What does sterile mean?

Answer 11

Environment free of life (microbes)

Question 12

What is induced immunity?

Answer 12

Body contains specific antibodies in response to specific antigens

Question 13

What is active immunity?

Answer 13

Long term immunity and involves the production of antibodies

Question 14

Give an example of natural active immunity

Answer 14

Antigen enters the body and white blood cells produce antibodies (get a disease)

Question 15

Give an example of artificial active immunity

Answer 15

Antigen enters the body by a vaccine and your body produces antibodies

Question 16

What is passive immunity?

Answer 16

Given made antibiotics

Question 17

Give an example of natural passive immunity

Answer 17

Antibodies enter via. breast milk or via. placenta

Question 18

Give an example of artificial passive immunity

Answer 18

Injected with antibodies e.g. tetanus injection

Question 19

Name three parts that make up the first line of the human defense system?

Answer 19

Skin - physical barrier
Clotting - If the skin is broken, blood clotting prevents entry
Cilia hairs - Prevent entry in respiratory system

Question 20

Name three parts that make up the second line of the human defense system

Answer 20

• White blood cells called macrophages (phagocytes) go to the site of attack and engulf any pathogen. This process is called phagocytosis. (Prevents pathogens attacking cells).
• Complimentary set of proteins are free in the plasma of the blood destroy pathogens as they move to the site of infection.
• Cells that are infected by viruses produce a protein called interferons which covers neighbouring cells preventing viral multiplication.

Question 21

What is the specific defense system

Answer 21

Attacks specific pathogens due to their antigens
Works by the production of antibodies

Question 22

What are the two types of antibodies?

Answer 22

Monocytes and lymphocytes

Question 23

Where are monocytes made?

Answer 23

In the bone marrow

Question 24

Where do monocytes mature?

Answer 24

Macrophages

Question 25

Where do monocytes move to?

Answer 25

Move in plasma or fixed in spleen or lymph nodes

Question 26

What do monocytes do?

Answer 26

Engulf pathogens

Question 27

Where are lymphocytes made?

Answer 27

Made in bone marrow

Question 28

Where are B lymphocytes made?

Answer 28

Made in the bone marrow

Question 29

Where do B lymphocytes mature?

Answer 29

Mature in bone marrow/ lymph nodes

Question 30

Where do B lymphocytes move to?

Answer 30

Move to spleen, lymph node

Question 31

What do B lymphocytes do?

Answer 31

Recognise a specific antigen on a pathogen and produce a specific antibody. Macrophages engulf and stop the infection

Question 32

Where are T lymphocytes made?

Answer 32

Made in the bone marrow

Question 33

Where do T lymphocytes mature?

Answer 33

Mature in thymus

Question 34

Do T lymphocytes produce antibodies?

Answer 34

No

Question 35

What switches on T lymphocytes?

Answer 35

The general defense system

Question 36

What is the function of helper T cells?

Answer 36

Activates B lymphocytes to replicate Activate T-killer cells and T suppressor cells

Question 37

What is the function of T killer cells?

Answer 37

Destroy cells infected by the virus/pathogen Destroy foreign bodies e.g. organ transplants Produce a chemical called perforin

Question 38

What is the function of T suppressor cells?

Answer 38

Infection is over Prevents the immune system and T killer cells from destroying all cells

Question 39

What is the function of T memory cells?

Answer 39

Long lived in the circulatory system Help the immune system to react quicker if infected again by the same antigen (immunity)