DAT bio chapter 11.3 human immune system

Question 1

The _____ are the first layer of innate immunity

Answer 1

outer walls

Question 2

Outer wall of the first layer of innate immunity consists of what

Answer 2

Skin
cilia
stomach acid
symbiotic bacteria

Question 3

Skin consists of

Answer 3

thick epidermis, dermis,
and hypodermis. Also mucous membrane
to trap pathogens and lysozyme to break
down bacterial cell walls. Has sebaceous
glands to secrete oil (sebum) as a barrier.
Sebum also has antimicrobial properties.

Question 4

cilia does what

Answer 4

• hair-like projections in the respiratory

tract that sweep away debris and pathogens.

Question 5

stomach acid does what

Answer 5

gastric acid that kills microbes

due to low pH.

Question 6

Symbiotic bacteria -

Answer 6

outcompete pathogenic

bacteria and fungi.

Question 7

When the first layer of innate immunity are penetrated, the _____system will kick in

Answer 7

immune

Question 8

5 signs of inflammation (DAT mnemonic

Answer 8

SLIPR
Swelling
Loss of function
Increased heat
Pain
Redness

Question 9

Swelling

Answer 9

permeable capillaries result in fluids

leaking into tissues.

Question 10

Loss of function

Answer 10

• body part with

inflammation becomes less usable.

Question 11

increased heat

Answer 11

increased blood flow results

in a higher temperature.

Question 12

pain

Answer 12

throbbing pain caused by swelling,
which puts continuous pressure on nerve
endings.

Question 13

redness

Answer 13

increased blood flow causes

redness of skin.

Question 14

Diapedesis

Answer 14

process by which cells move
from the capillaries to the tissues in order to fight
pathogens.

Question 15

Chemotaxis

Answer 15

method by which cells move
in response to a chemical signal. Immune cells
use chemotaxis to move to the tissues.

Question 16

Five main types of leukocytes from highest to
lowest in quantity → Never Let Monkeys Eat
Bananas

Answer 16

Never Let Monkeys Eat
Bananas
- neutrophil
-lymphocytes
-macrophages
-eosinophils
-basophils

Question 17

Neutrophils

Answer 17

phagocytes in innate immunity

that make up over half of all leukocytes.

Question 18

lymphocytes

Answer 18

• B cells, T cells, and natural
  killer cells. B and T cells are part of adaptive
  immunity and must be activated. Natural
  killer (NK) cells are part of innate immunity
  and attack virally-infected cells + cancerous
  cells. NK cells use perforin (create holes) and
  granzyme (stimulate apoptosis) to lyse cells.

Question 19

macrophages/monocytes

Answer 19

- phagocytes in
innate immunity. Monocytes are the
immature form found in blood vessels and
macrophages are the mature form after
diapedesis. Can also act as antigen-presenting
cells to activate adaptive immunity.

Question 20

eosinphils

Answer 20

part of innate immunity and
have granules that can be released to kill
pathogens, especially parasites.

Question 21

basophils

Answer 21

least numerous leukocyte;
contains granules with histamine
(vasodilation) and heparin (an anticoagulant
to prevent blood clotting). Very similar to
mast cells, except basophils circulate as
mature cells while mast cells circulate as
immature cells.

Question 22

Dendritic cells are part of ____ immunity and scan tissues using _____ and ____

Answer 22

innate
pinocytosis
phagocytosis

Question 23

dendritic cells also act as

Answer 23

antigen-presenting cells like macrophages,
migrating to the lymph nodes to activate
adaptive immunity.

Question 24

interferons are secreted by what and bind to what

Answer 24

virally infected cells,

bind to non infected cells to prepare them for a virus attack. also help activate dendritic cells

Question 25

complement system: complement system) is a group of | approximately_____-

Answer 25

approximately 30 proteins that aid immune cells in fighting pathogens. These proteins turn each other on through the complement cascade, which amplifies the complements effects by releasing cytokines.

Question 26

Complement protein actions:

Answer 26

Tags antigens for phagocytosis in a process called opsonization ● Amplifies inflammatory response Eg. binds to mast cells for increased histamine release ● Forms a membrane attack complex (MAC), which pokes holes in pathogens and lyses them

Question 27

adaptive immune system is a what

Answer 27

``` specific immune response (targets specific antigens). ```

Question 28

What is an antigen

Answer 28

an immunogenic foreign molecule | and is the target of the immune response.

Question 29

What is the epitope?

Answer 29

important part of the antigen that | is recognized by the immune cell.

Question 30

How does immune system recognize self proteins from non self proteins?

Answer 30

``` They use major histocompatibility complex (MHC), which is found on the surface of cells ```

Question 31

foreign antigens and foreign MHC will be identified as enemies by the ______

Answer 31

immune system

Question 32

what is the surface molecule present on all nucleated cells, and each genetically different individual will have a different MHC I molecule.

Answer 32

MHC class 1

Question 33

Organ transplants that have different ___I may lead to failure and rejection, so immunosuppressants are given to transplant patients.

Answer 33

MHC I

Question 34

When does autoimmune diseases occur

Answer 34

when | the immune system attacks self MHC I.

Question 35

_____surface molecule present on antigen-presenting cells (dendritic cells, macrophages) _______

Answer 35

MHC Class II is used to present foreign antigens to activate immune cells.

Question 36

b cells control

Answer 36

antibody-mediated immunity (humoral immunity) by managing the production and release of antibodies. They can also act as antigen-presenting cells.

Question 37

B cell receptors (BCRs) are located on

Answer 37

B cells and bind to antigen epitopes either free-floating or on APCs. Each B cell has a unique BCR.

Question 38

The clonal selection model describes the | development of _____

Answer 38

one type of BCR for every B cell.

Question 39

Through clonal expansion, what happens

Answer 39

these B cells divide into either plasma cells (antibody-secreting cells) or memory B cells (to be activated later in case of another attack).

Question 40

Antibodies (immunoglobulins)

Answer 40

structurally identical to BCR but freely circulate in blood and lymph

Question 41

Function of antibodies

Answer 41

tag antigens for phagocytosis, neutralize the antigen by coating it, or activate the complement system.

Question 42

Structure of antibodies

Answer 42

Antibodies contain light chains and heavy chains linked by disulphide bonds. In addition, the variable region recognizes different antigens while the constant region is the same for antibodies within the same class.

Question 43

DAT Mnemonic: | Classes of Antibodies → Me And Eve Don’t Go

Answer 43

``` IgM igA igE igD igG ```

Question 44

IgM

Answer 44

present in a pentameric form and is the largest antibody. The first antibody to be produced; activates the complement system.

Question 45

IgA

Answer 45

- present in a dimeric form and found most abundantly in bodily secretions. Newborns receive passive immunity through breast milk containing IgA. Also, IgA mainly binds pathogens externally, outside of circulation.

Question 46

igE

Answer 46

monomer that is present on basophils and mast cells as antigen receptors. When bound to an allergen, triggers histamine release and an allergic reaction.

Question 47

igD

Answer 47

monomer that we have very little information about. Only small amounts are produced.

Question 48

igG

Answer 48

monomer that is the most abundant antibody in circulation. Also the only antibody that can cross the placenta to give fetus passive immunity. Helps the complement system to cause opsonization (tags antigens and subsequent phagocytosis).

Question 49

Memory B cells do what

Answer 49

survive for a long time and lay dormant until reactivated by the same antigen that triggered the original clonal expansion.

Question 50

Memory B cells are key to ____

Answer 50

vaccinations because vaccines cause memory B cell production for later reactivation. After reactivation, memory B cells cause massive antibody production.

Question 51

T cells control what

Answer 51

cell-mediated immunity by directly acting on cells instead of sending antibodies out.

Question 52

T cell receptors (TCRs) are what

Answer 52

are unique just like BCRs, binding only to one type of antigen per T cell. Thus, T cells also undergo clonal selection just like B cells.

Question 53

T cells must bind to antigens presented on what to be activated

Answer 53

presented on APCs | (antigen-presenting cells) to be activated.

Question 54

There are two ways antigens may be presented | to T cells:

Answer 54

MHC I Presentation: | MHC II Presentation:

Question 55

MHC I Presentation:

Answer 55

T cells differentiate into CD8 T cells (cytotoxic T cells), which directly kill infected cells through perforin (poke holes) and granzymes (cause apoptosis). However, T cells are different from natural killer cells because they are more specific and require antigen presentation.

Question 56

MHC II Presentation:

Answer 56

T cells differentiate into CD4 T cells (helper T cells), which release cytokines to boost both innate immunity and adaptive immunity. These cytokines help attract innate immune cells and increase proliferation of other T and B cells.

Question 57

Passive immunity refers to what

Answer 57

immunity one organism gains from receiving the antibodies from another organism that already has that immunity.

Question 58

ex of passive immunity

Answer 58

fetus gains passive immunity through the placenta (IgG) while a newborn gains passive immunity through breast milk (IgA).

Question 59

When fetus do not have their own active immunity what is it called?

Answer 59

immuno-naive

Question 60

Active immunity refers to

Answer 60

immunity an organism gains from being infected once already by a pathogen. A vaccination introduces the antigen or pathogen in a deactivated state to stimulate active immunity, which is referred to as artificial immunity in this case and induces memory B and T cell formation.