bio ch 8 immune system

Question 1

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

Answer 1

innate - non-selective targets, unable to recognize specific pathogens. responsible for general disease prevention

adaptive - selective targets. adapts to environment and recognizes and eliminates specific pathogens

Question 2

What are the two subdivisions of the innate immune system and how are they different

Answer 2

Non-cellular component -consists of physical barriers as well as signaling molecules

Cellular component -consist of various types of white blood cells directly involved in recognizing destroying in a golfing pathogens

Question 3

What are some of the anatomical barriers of the innate immune system?

Answer 3

Skin
The G.I. tract
Saliva, stomach, peristalsis, gut flora
The respiratory system
mucus

Question 4

List out the cellular components of the innate immune system

Answer 4

Neutrophils
Lymphocytes (NK Cells)
Monocytes
Eosinophils
Basophils

Question 5

What are neutrophils and what do they do

Answer 5

Neutrophils are the most abundant type of white blood cell and are often the first responder to infection so elevated neutrophil levels can indicate infection. They have the ability to phagocytose

Question 6

What are lymphocytes and what do they do?

Answer 6

Lymphocytes are the second most common type of white blood cell and their three types
B cells
T cells
Natural killer cells

Only the natural killer cells are a part of the innate immune system while B and T cells are part of the adaptive

Question 7

What Are natural killer cells

Answer 7

Natural killer cells are type of lymphocyte a part of the innate immune system which respond to cells infected by viruses and cancerous tumors to kill them and prevent spread of infection.

Question 8

What are monocytes?

Answer 8

The third most abundant type of white blood cell which differentiates into dendritic cells or macrophages

Question 9

What are dendritic cells?

Answer 9

Cells which are derived from monocytes, they serve as the bridge from the innate system to the adaptive immune system by presenting antigens to T cells

Question 10

What are macrophages?

Answer 10

a cell derived from monocytes which are known as the “garbage cans”” of the body because they consume “phagocytose” particles/pathogens which don’t belong

Question 11

What are Eosinophils

Answer 11

A type of innate immune WBC that targets parasitic infections

Question 12

what are mast cells and how do they differ from basophils

Answer 12

similiar to basophils except they are found in mucous membranes and connective tissues. They are not found in the blood stream where as basophils are

Question 12

What are basophils

Answer 12

An innate immune WBC which contributes to the allergy response by releasing histamine and heparin

Question 13

what are granulocytes

Answer 13

granulocytes are a category of WBC’s which contain granules in their cytoplasm. Granules containn ezymes capable of combating pathogens and mediating inflammation.

Question 14

what are some WBCs which are granulocytes

Answer 14

Neutrophils, eosinophils, and basophils are all granulocytes

the -phil wbcs

Question 15

What are phagocytes

Answer 15

Cells capable of phagocytosing
Includes neutrophils, monocytes, Macrophages, and dendritic cells.

Question 16

what is an antigen

Answer 16

a foreign (non self) or self substance which is recognized by the immune system as either foreign or self and initiates an immune response based on that.

Question 17

What is the complement system and what are some of the ways it works?

Answer 17

A part of the immune system that “complements” or enhances the immune response.

It does this in a few ways

1. opsonization - complement proteins coat the surface of pathogens marking them for destruction via phagocytosis
2. cell lysis- complement proteins create a membrane attack complex (MAC) which creates holes in the cell membrane of a pathogen leading to cell lysis

3 . Chemotaxis and inflammation

chemotaxis - complement proteins release chemical signals “attracting” immune cells to the site of an infection

inflammation - complement proteins promote inflammation

Question 18

what are cytokines?

Answer 18

signaling proteins that relay information which helps to regulate the immune response. There are many types of cytokines

Question 19

what are interleukins and interferons?

Answer 19

Both are types of cytokines.

Interleukins - regulate growth, activation, and differentiation of immune cells

interferons- are released by infected cells when certain receptors are triggered. thely help to inhibit viral replication and also upregulate the rest of the immune system .

Question 20

what is the cause of inflammation aka swelling and what cells contribute to the inflammation response?

Answer 20

inflammation is a response to cell injury or pathogen exposure.

Cells of the innate immune system (macrophages, dendritic, and mast cells) go to the area and cause vasodilation allowing additional blood and plasma into the area which allows more immune cells to enter.

Question 21

What is the purpose of the Adaptive immune system

Answer 21

to adapt to the environment and learn to recognize and eliminate SPECIFIC pathogens

Question 22

What are the 2 main cells of the adaptive immune system and their overarching functions

Answer 22

B cells- create antibodies which creates humoral immunity

T cells- create cell-mediated (cytotoxic) immunity

Question 23

Where are B and T cells produced?

Answer 23

Both B and T cells are produced in the bone marrow and both need to mature after production.

Question 24

What happens during naive B cell maturation and where does maturation occur?

Answer 24

Naive B cells undergo random recombination, where parts of B cell nucleic DNA are randomly altered allowing them to express a wide variety of antigen receptors.

B cells mature right in the bone marrow where they produced, then they travel to the lymph nodes and aggregate there.

Question 25

What is clonal selection ?

Answer 25

Selection of a
B (or T) cell which has bound to it’s
antigen to undergo clonal expansion (proliferation)
creating a large # of identical B cells w/
the same antigen specificity

Question 26

What are the 2 types of cells a B cell can differentiate into one clonal expansion starts and what do they do?

Answer 26

Memory B cells - remain in lymph nodes until antigen reappears in body (immunity)

Effector (Plasma) B cells - produce antibodies which neutralize the pathogen

Question 27

Primary vs secondary immune response

Answer 27

Primary - the initial response to an antigen for the first time. Is a slower and weaker response than secondary.

Secondary- much faster and stronger response to an antigen which reappears in the body thanks to memory B cells. Symptom rarely develop if at all

Question 28

What happens during naive T cell maturation and where does maturation occur?

Answer 28

T cells undergo random recombination like B cells.

Positive and negative selection also occurs.

Positive selection- a process which eliminates T cells which fail to bind to Self-MHC molecules

Negative selection- elimination of T cells which bind too harshly/strongly to Self-MHC molecules as this could lead to autoimmune disease

T cell maturation occurs in the Thymus

Question 29

What are the T cell subtypes and what do they do?

Answer 29

Helper T cells - Aka CD4+ cells, these help to activate B cells (for antibody production) , Cytotoxic T cells (to kill infected cells), and macrophages (enhance phagocytosis)

Cytotoxic T cells -aka killer T cells aka CD8+ T cells, bind to infected or cancerous cells displaying foreign antigens on its MHC1 and release perforin and granzymes to kill the targeted cell

Question 30

What do the perforin and granzyme enzymes released by cytotoxic T cells do respectively?

Answer 30

Perforin- creates pores in the target cell’s membrane

granzymes- enters thru the pores and induces apoptosis in the cell

Question 31

What are MHC (major histocompatibility complex) proteins

Answer 31

Protein complexes present on the surface of cells which bind to and display antigenic peptides for T cells to recognize and respond to .

Question 32

Difference betwwen Class 1 and class 2 MHC proteins ?

Which cells they are presented on?
What kind of antigens do they display?
Which cell recognizes their antigens?

Answer 32

MHC 1
- present on almost all nucleated cells
-presents endogenous antigens ( antigens that originate from inside the cell) on the cell surface
-are recognized by CD8+ cytotoxic T cells, which killed cells that present abnormal or foreign antigens

MHC 2
- Present on Antigen-presenting Cells (APC’s) only — Dendritic cells, macrophages, and B cells
-Presents exogenous antigens (antigens which originate from outside the cell)
- are recognized by CD4+ helper T cells which helps to coordinate immune response by activating other immune cells

Way to remember MHC 1 and 2 correspond to CD8+ and CD4+

multiply the MHC number to get 8

MHC 1 *8 = 8 = CD8

MHC 2 *4=8 = CD4

Question 33

What is hematopoiesis and where does it take place?

Answer 33

Hematopoiesis is the production of blood cells and it takes place in the bone marrow.

Question 34

what happens in the spleen as it relates to the immune system?

Answer 34

The spleen can be thought of as a blood recycling center where damaged and old Red blood cells get components like hemoglobin and iron recycled.

The spleen also contains a reservoir of healthy blood in case of emergencies.

Question 35

What is white pulp?

Answer 35

An area of the spleen that contains a large number of lymphocytes (B and T Cells) and monitors the blood for pathogens much like the immune cells in the lymph nodes monitor the lymph fluid.

Question 36

What happens in the Thymus as it relates to the immune system?

Answer 36

The tyhmus is where Naive T cells are sent to mature and differentiate after being produced in the bone marrow. Positive and negative selection of T cells occurs here.

Question 37

What role does the lymphatic system play for the circulatory and the immune systems respectively?

Answer 37

In the circulatory system, the LS helps to maintain fluid pressure throughout the body by collecting excess blood which leaks out of capillaries and becomes nutrient-rich interstitial fluid and prevents it from pooling up and causing swelling and edema. The lymphatic system eventually returns the fluid into the blood stream.

For the immune system the LD contains hundreds of lymph nodes which serve as filters for lymph and are reservoirs memory Band T cells. The Spleen and Thymus are also included as part of the LS

Question 38

epitope vs paratope

Answer 38

epitope is the region on an antigen which the antibody recognizes and binds to

paratope is the specific part on the antibody which binds to the epitope of the antigen

Question 39

purpose of the constant region of an antibody

Answer 39

for recognition by other immune cells as well as determining the class of the antibody

Question 40

what are the different classes of antibodies

Answer 40

antibodies aka immunoglobulins (Ig)

IgA- Found in mucosal areas (e.g., respiratory and digestive tracts) and secretions like saliva and tears, it helps protect body surfaces exposed to external pathogens.

IgD- Found mainly on the surface of immature B cells; its specific function is less understood but thought to play a role in initiating B cell activation.

IgE- Involved in allergic reactions. binds to allergens and triggers histamine release from mast cells.

IgG - Majority of the antibodies in the blood; able to cross placental barrier

IgM - First antibody produced in response to an antigen

Question 41

what is an allergic reaction

Answer 41

a hypersensitive rxn by the immune system mounted against a foreign particle normally regarded as harmless like pollen pet hair and foods.