The immune system

Question 1

Immune cells originate in the ______

Answer 1

Bone marrow

Question 2

What is the difference between the innate and adaptive immune system?

Answer 2

The innate immune system is always active, but does not respond to specific threats. For this reason, it’s also called non-specific immunity

The adaptive immune system is active only when there is a threat, so it’s slower to act but develops ways to fight against specific pathogens and maintains memory of them in the case of reinfection. Called specific immunity

Question 3

This type of immunity occurs when antibodies act in the blood instead of within the cell

Answer 3

Humoral immunity

Question 4

In the adaptive immune system, humoral immunity is driven by _____ while cell-mediated immunity is driven by ____

Answer 4

B cells (humoral immunity is done via antibodies)

T cells (cell-mediated immunity involves attacking the cell directly)

Question 5

This non-cellular defense is a bacterial enzyme found in saliva and tears

Answer 5

Lysozymes

Question 6

This non-cellular defense is made up of blood proteins that destroy bacteria by punching holes in their cell wall and disrupting their osmotic regulation. The proteins do this by either the classical (requiring antibodies) or alternative (not requiring antibodies) pathway

Answer 6

The compliment system

Question 7

These proteins are released by a virus-infected cell. They prevent viral replication, alert nearby cells to decrease their protein production and be on alert, and upregulate MHC I and II to tell the immune system about the infection

Answer 7

Interferons

(Interfering with the viruses ability to transmit)

Question 8

These cells are part of the innate immune system, originate as monocytes and take up permanent residence in tissues (meaning they don’t migrate around). They perform three duties: Phagocytize invader –> digest invader and break into smaller parts –> bring to the invader to other cells using MHC so that it may be recognized by other immune cells. They also create an inflammatory response

Answer 8

Macrophages

Question 9

What is the difference between MHC I and MHC II?

Answer 9

MHC I is produced by all nucleated cells. It’s referred to as the endogenous pathway because it deals with proteins already in the cell, and alerts the T-cells to kill the infected cell

MHC II is only produced by professional anti-gun producing cells (like macrophages). It’s referred to as the exogenous pathway because it deals with proteins that have come from outside the cell

Question 10

How are macrophages and dendritic cells, among others, able to identify the invader and create the appropriate response?

Answer 10

They have pattern recognition receptors which determine what class the pathogen falls into and what is the best defense against it

Question 11

These cells are non-specific lymphocytes that detect low levels of MHC on cells and induce apoptosis

Answer 11

Natural killer cells

Question 12

These granulocytes are the most populous granulocyte in the blood but only live for about 5 days. They are phagocytic and target bacteria through chemotaxis, meaning they’re able to follow the chemicals released by bacterial movement and find the source

Answer 12

Neutrophils

Question 13

These granulocytes release histamines in response to allergens or parasites

Answer 13

Eosinophils

Question 14

These granulocytes are the least populous granulocyte in the blood. They react like mast cells to allergens, releasing histamines

Answer 14

Basophils

Question 15

These cells of the adaptive immune system mature in the spleen and bone marrow and produce one type of antibody each.

Answer 15

B-cells

Question 16

What are the two classes of agranulocytes?

Answer 16

Lymphocytes (B and T cells) and monocytes (macrophages)

Question 17

What are the three granulocytes?

Answer 17

Eosinophils, neutrophils and basophils

Question 18

This cell class contain granulocytes and agranulocytes

Answer 18

Leukocytes

Question 19

How do the granules on granulocytes attack invaders?

Answer 19

They work through exocytosis in the cytoplasm. Toxic chemicals/enzymes attack bacteria, fungi and parasites

Question 20

These cells of the adaptive immune system mature in the thymus and are responsible for cell-mediated response

Answer 20

T-cells

Question 21

What is the difference between passive and active immunity?

Answer 21

Passive immunity is acquired when antibodies are injected into the patient, so the immunity doesn’t require any effort from the patient

Active immunity occurs when the pathogen is introduced and the body makes its own antibodies in response

Question 22

Antibodies are Y shaped and have __ heavy chains and __ light chains

Answer 22

2 and 2

Question 23

These cells capture, process and present antigens to lymphocytes in order to activate the adaptive immune system

Answer 23

Dendritic cells

Question 24

How do B-cells attack pathogens? (including where they stay, what kind of cells they create, and the two kinds of response)

Answer 24

B-cells wait in the lymph nodes until they’re exposed to the correct antigen. Then they create two daughter cells: a plasma cell that increases the amount of antibodies produced, and a memory cell that stays in the lymph node for future infection.

B-cells also have primary and secondary responses. The primary response is the initial division occurring during the first infection, and the secondary response is the subsequent attack when the left over memory cell divides into a plasma and memory cell to combat infection

Question 25

What are the three methods by which antibodies attack antigens?

Answer 25

-Can bind to the antigen and attract leukocytes to phagocytize (called opsonization)
-Can clump antigens together (auggluntinization)
-Can block pathogen invasion by activating B-cells or causing structural changes on the cell surface

Question 26

T cells undergo two types of selection: positive for _____ and negative for ____

Answer 26

Positive for mature cells that can recognize MHC

Negative for mature cells that cannot recognize MHC and undergo apoptosis

Question 27

In this type of selection, only the cells that are the best at their job survive. Ex: B-cells with the best match to their antigen survive because they’re able to react the fastest

Answer 27

Clonal selection

(only the best at their job survive in order to make sure the pathogen can be fought off as efficiently as possible)

Question 28

These T cells recognize MHC II, so they are most effective against bacteria. They secrete lymphokines that recruit other immune cells

Answer 28

Helper T-cells (CD4+ T)

(Help the body mount a better response against the invader)

Question 29

These T cells recognize MHC I, so they are most effective against viruses. They kill cells by injecting them with toxins that induce apoptosis

Answer 29

Killer (cytotoxic) T-cells (CTL, CD8+)

Question 30

These T-cells tone down the immune response once infections have been contained

Answer 30

Suppressor T-cells

Question 31

These T-cells wait for the next exposure

Answer 31

Memory T-cells

Question 32

These antigens are present on the surface of every native cell in order to let the immune system know the cell isn’t foreign. Autoimmunity occurs when the immune system is not able to recognize these antigens

Answer 32

Self-antigens

Question 33

B-cells proliferate and develop in this system. It’s made of one-way vessels that increase in size the closer they get to the center of the body and drain into the subclavian vein

Answer 33

Lymphatic system

Question 34

These nodes provide space for immune cells to be exposed to pathogens, return excess fluid from tissues to veins, and transport biomolecules (like fats) out of the digestive system and into the blood

Answer 34

Lymph nodes