1. Figure 43.1 An overview of the body's defenses
Chapter 43 Immune System
Figure An overview of the body's defenses
Traps microbes
Lymphocytes –
Antibodies - proteins that
attack
- edema (swelling) -
B cells
T cells
Ex. Lysozyme - protective
protein
Found:
Opeing around eyes (tears,
mucus)
redness
upper respiratory
tract
pain
antigens
(foreign molecules)
blood flow
Ex. Interferons - secreted by
virus infected Bells, causes other
cells to produce chemicals to
inhibit viral reproduction

2. Figure 43.4 The human lymphatic system-
- location where
returns fluid from interstitial spaces
lymphocytes
develop
T cells
B cells
Leukocytes – any white blood cell
B cells
T cells
Macrophages
Monocytes

3. Figure 43.5 A simplified view of the inflammatory response
triggers
inflamation
Injured cells release chemicals:
1. Histamine - causes dilation of ________________ and increases permeability of _______________
2. Prostaglandins - also ________________________________________________________
Fever can also result from infections
- moderate fever helps with defense by _______________________________________________ -
- increase body reactions for ___________________________
* septic shock - caused by a large systemic inflammatory response
blood vessels
capillaries
promotes blood flow
inhibiting growth of microorganisms
facilitates phagocytosis
repair
high fever
low blood pressure

5. Figure 43.6 Clonal selection
Antigens activate specific
2 types: 1. 2.
B cells
T cells
foreign
Different receptors on B cells -
Membrane antibodies
also called
only one receptor fits
the antigens shape
membrane
immunoglobulins
Ex. Occurs due to:
virus
bacteria
fungi
protozoa
parasitic worms
pollen
Clone of B cells
Clone of B cells can either
develop into:
memory cells
clone plasma cells
effector cells
Short lived plasma cells, also called
Secrete
Specific
Long lived cells: can respond quickly to the next
to the same
antibodies
to the antigen

6. Figure 43.7 Immunological memory
Primary immune
response
Responsible for initiating a
• Effector
plasma cells
•Effector
B cells
Memory cells proliferate at:
secondary immune
response
initial exposure and second
exposure
(make antibodies)
T cell response

7. Figure 43.8 The development of lymphocytes
white blood cells
Lymphocytes are
Two types:
T cells (develop in thymus)
B cells (develop in bone marrow)
Found:
B cells and T cells must distinguish self from
nonself, if not: -
autoimmune diseases, have no
self tolerance
Both B and T cells have specific
antigen receptors
Develops in:
Develops in:

9. Figure 43.9 The interaction of T cells with MHC molecules
Antigen presenting cell:
APC
Found on:
Found on:
- macrophages
- B cells
- T cells
- inside
thymus
almost every
cell in the
body
Major histocompatibility complex -
distinguishes self from non-self
identifies abnormal cells

10. Figure 43.10 An overview of the immune responses
Involves B cell activation
with the production of
antibodies
Defends against:
Involves cytotoxic
T cell activation
Defends against:
1. cells infected
by virus or
bacteria
2. fungi
3. protozoa
4. parasitic worms
responds to
transplants and
cancer cells
1. free bacteria
2. toxins
3. viruses in body
fluids

11. Figure 43.11 The central role of helper T cells: a closer look
protein
antigen presenting cell
other lymphocytes
Cytokines - proteins that stimulate ex. interleukin 1, interleukin 2
1. APC engulfs bacteria, transports to ______________________________________________
2. A specific TH cell binds to the __________________________________________________
interleukin-1 secreted by the __________________________________________________
3. TH cell proliferates into more___________________________________________________
other cytokines and interleukin-2 are secreted
4. Cytokines stimulate __________________________________________________________
the surface using a class II MHC molecule
MHC antigen complex
APC enhances TH cells to secrete interleukin-2
TH cells and memory T cells
TH cells and activates B cells and TC cells

13. Figure 43.12a The functioning of cytotoxic T cells
antigen using a class I MHC molecule
1. Infected cells displays _______________________________________________________
TC cell binds to the __________________________________________
2. TC cell releases ______________ creates pores in the membrane of the infected _______
3. Water and ions flow _________________________ ________________________
MHC antigen complex
perforin
cell
into infected cell
cell lysis

14. Figure 43.13 Humoral response to a T-dependent antigen

16. Figure 43.14 Epitopes (antigenic determinants)
Antibodies -
a group of proteins called
immunoglobulins
disease or vaccination
Active immunity - immunity from an infectious _________________________________________
Passive immunity - mother to fetus through the __________________
passes __________________ also through ________________________________
Blood type: type A blood contains _______ antigens
type B blood contains _______ anitgens
type AB blood contains _______ antigens
type O blood contains _______ antigens
Rh factor can cause fetus RBC’s to be destroyed
placenta
antibodies
breast milk A
antibodies
*blood contains _______________
to fight ____________________
after a transfusion B
antigens
A, B no

17. Figure 43.16 Effector mechanisms of humoral immunity

19. Figure 43.20 The stages of HIV infection