Cellular Immune Response, Transplants, & Disorder/Diseases

Question 1

How are T cells activated?

Answer 1

By binding with recognized antigens

Question 2

What must the antigen be presented by for the T cells to activate?

Answer 2

Macrophages must present the antigen to the T cells

Question 3

What is essential for activation and clonal selection of cells?

Answer 3

Antigen presentation

Question 4

What do APCs do with antigens? (2)

Answer 4

1. Engulf the antigen

2. Process it

Question 5

How do T cells notice the “non-self” and “self” types?

Answer 5

By coupling with specific glycoproteins and APCs surface

Question 6

State the specialization of cytotoxic T cells and describe its attack. (6)

Answer 6

1. Specialize in killing viral infections (cancer or foreign cells)
2. Bind tightly to foreign cells
3. Release toxic chemicals called perforin and granzymes from its granules
4. Enters the foreign cell’s plasma membrane → lethal hit → pores appear in the target cell’s membrane
5. The granzymes (protein-digesting enzymes) are then able to enter and kill the foreign cell
6. Cytotoxic T cell then detaches and seeks other prey to attack

Question 7

What are the two toxins that cytotoxic T cells release? (2)

Answer 7

1. Perforins

2. Granzymes

Question 8

Describe the role of helper T cells (5)

Answer 8

1. Circulate through the blood recruiting other cells to fight off invaders
2. Release a variety of cytokine chemicals that act to rid the body of antigens by
3. Circulating cytotoxic T cells and B cells to grow and divide
4. Attracting other types of white cells (neutrophils)
5. Enhancing the ability of macrophages to engulf and destroy microorganisms

Question 9

List and briefly describe the 4 types of grafts. (4)

Answer 9

1. Autograft - tissue transplanted from one site to another on the same body
2. Isograft - tissue graft is taken from one with the same genetics (twins only)
3. Allograft - tissue is taken from a person who isn’t an identical twin
4. Xenograft - tissue is harvested from a different animal species

Question 10

How do disorders of immunity occur? (3)

Answer 10

1. Body (immune system) loses the ability to determine “friend or foe”
2. Body produces antibodies (auto-antibodies) → T cells attack itself and one’s own tissue
3. Allergies = hypersensitivities

Question 11

What major effect does rheumatoid arthritis (RA) have on the body?

Answer 11

Rheumatoid arthritis (RA) → destroys joints

Question 12

What major effect does myasthenia gravis have on the body?

Answer 12

Myasthenia Gravis → Impaired communication with nerves and skeletal muscles

Question 13

What does multiple sclerosis do to the body?

Answer 13

Multiple Sclerosis → Destroys white matter of the brain and spine

Question 14

What is the main sign of graves’ disease?

Answer 14

Graves’ Disease → thyroid produces too much thyroxine

Question 15

What does type 1 diabetus mellitus do to the body?

Answer 15

Type 1 diabetus mellitus → destroys pancreatic beta cells, resulting in the deficient production of insulin

Question 16

What is systemic lupus erythematosus (SLE)

Answer 16

Systemic lupus erythematosus (SLE) → systemic disease that occurs mainly in young women and particularly affects the kidneys, heart, lungs, and skin

Question 17

What is glomerulonephritis?

Answer 17

Glomerulonephritis → severe impairment of kidney function due to acute inflammation

Question 18

State the role of regulatory T cells and how it fulfills its role. (2)

Answer 18

1. Help prevent uncontrolled or unnecessary immune system activity
2. Release chemicals that suppress the activity of both T and B cells

Question 19

Define: memory cells

Answer 19

long-lived B and T cells that remain behind to provide immunological memory for each antigen encountered and enable the body to respond quickly to subsequent invasions