U3: 22- Specific Cellular Defences Against Pathogens

Question 1

Is the 3rd line of defence described as specific or non-specific?

Answer 1

Specific

Question 2

Which group of cells in the immune system bring about a specific immune response?

Answer 2

B-Lymphocytes and T-Lymphocytes

Question 3

All lymphocytes originate in the bone marrow. If they pass to the thymus to mature what do they become?

Answer 3

T-Lymphocytes

Question 4

If lymphocytes complete their maturation in the bone marrow what do they become?

Answer 4

B-Lymphocytes

Question 5

What name is given to any foreign molecule that is able to elicit a specific immune response from a lymphocyte?

Answer 5

Antigen

Question 6

Give some examples of antigens.

Answer 6

Bacteria, viruses, cancer cells, molecules on the surface of transplanted cells

Question 7

There are a number of different lymphocytes. What is found on the surface of every lymphocyte that makes each lymphocyte different?

Answer 7

A different antigen receptor

Question 8

What are the antigen receptors on the surface of lymphocytes specific to?

Answer 8

One type of antigen

Question 9

Whenever an antigen attaches to the specific antigen receptors on a lymphocyte the lymphocyte is activated and responds by dividing repeatedly to form identical lymphocytes. What is this called?

Answer 9

A clonal population

Question 10

Whenever an antigen enters the body the B-Lymphocytes respond by producing what?

Answer 10

Antibodies

Question 11

What shape is an antibody?

Answer 11

Y-shaped

Question 12

What is found at the end of each arm of the Y-shaped antibody?

Answer 12

A receptor specific to a particular antigen

Question 13

When a B-Lymphocyte becomes activated by the presence of an antigen it responds by making a clone of B-Lymphocytes which all make antibodies. What other cells are made to produce the same antibodies if they are needed in the future?

Answer 13

Memory B-Lymphocytes

Question 14

What name is given to the combination formed when the antibody binds to the antigen?

Answer 14

Antigen-antibody complex

Question 15

The formation of the antigen-antibody complex makes the pathogen more susceptible to…?

Answer 15

Inactivation of it or the toxin it produces and phagocytosis

Question 16

What happens when B-Lymphocytes respond to a harmless substance such as pollen, dust or feathers?

Answer 16

An allergic reaction occurs

Question 17

In hay fever, which is an allergic reaction, B-Lymphocytes produce antibodies which then attach to which cells in the connective tissue?

Answer 17

Mast cells

Question 18

During an allergic reaction mast cells over produce a substance which causes nasal congestion and constricted airways. What is this substance?

Answer 18

Histamine

Question 19

During anaphylactic shock lots of histamine is released so the blood vessels undergo extreme vasodilation. What does this do to blood pressure that can potentially result in death?

Answer 19

Blood pressure drops suddenly

Question 20

Whenever a phagocyte captures a pathogen it normally presents some of the pathogen’s antigen on the phagocyte surface. What name is given to the phagocyte in this state?

Answer 20

Antigen-presenting cell

Question 21

What recognises and binds with these antigens on the surface of an antigen presenting cell?

Answer 21

A T-Lymphocyte that has the specific antigen receptor that recognises that particular antigen

Question 22

When an antigen-presenting cell becomes attached to a T-Lymphocyte what two things happen?

Answer 22

A clonal population of T-Lymphocytes are made as well as memory T-Lymphocytes

Question 23

The T-Lymphocytes destroy the infected body cells by which process?

Answer 23

Apoptosis (programmed cell death)

Question 24

Apoptosis by T-Lymphocytes destroy the majority of the infected cell, however, the cell membrane of the infected cell is not destroyed. What process follows apoptosis to remove the remaining parts of the dead cell?

Answer 24

Phagocytosis

Question 25

What name is given to cells that the body recognises as part of that person and unique to them?

Answer 25

Self cells

Question 26

Normally T-Lymphocytes do not attack self cells and only attack non-self cells. If they do attack self cells what is this called?

Answer 26

Autoimmunity

Question 27

What autoimmune disease is characterised by the T-Lymphocytes attacking the insulin producing cells in the pancreas?

Answer 27

Type 1 diabetes

Question 28

Name an autoimmune disease where the joints become inflamed.

Answer 28

Rheumatoid arthritis

Question 29

What name is given to the first time the body produces antibodies to a disease?

Answer 29

Primary response

Question 30

If a person survives an earlier exposure to a certain pathogen and then becomes exposed again later what response kicks in?

Answer 30

Secondary response

Question 31

In which 3 ways is the secondary immune response better than the primary immune response in preventing a disease the second time round?

Answer 31

Antibody production is more rapid, produced at a higher level and lasts for a longer time

Question 32

Which cells ensure that the secondary immune response is made possible?

Answer 32

Memory cells

Question 33

Which lymphocytes are attacked by HIV (Human Immunodeficiency Virus)?

Answer 33

T-Lymphocytes

Question 34

Which disease follows HIV where the person is susceptible to opportunistic infections such as pneumonia and rare forms of cancer because their immune system is so weak?

Answer 34

AIDS (Acquired Immune Deficiency Syndrome)