Chapter 31-32

Question 1

What are the types of immunity?

Answer 1

nonadaptive (innate) and adaptive

Question 2

antigens

Answer 2

any substance recognized by the immune system
Immune system can differentiate between self-antigen and non-self (foreign) antigen

Question 3

what is the difference between infection and disease?

Answer 3

Contact with an infectious agent does not guarantee that a person will actually contract the disease
Has to go through all of body’s defenses to disease someone

Question 4

what are the barriers in innate immunity?

Answer 4

skin, mucous membranes, and chemical

Question 5

What is significant about the skin as a barrier?

Answer 5

epithelial cells, Mechanical barrier to
microbial invasion

Question 6

Keratinocytes

Answer 6

cells in outer layer of skin

Question 7

what are the significant cells in the mucous membranes in innate immunity?

Answer 7

*Epithelial cells
* Goblet cells—produce mucus
* Paneth cells—secrete antimicrobial peptides.

Question 8

What is significant about the respiratory system in innate immunity?

Answer 8

microbes stopped by hairs and cilia in nose, if it makes it past than it is caught by the mucociliary escalator

Question 9

what is the mucociliary escalator?

Answer 9

Moves particles away from the lungs towards the mouth.
* Coughing and sneezing clear respiratory system

Question 10

Alveolar macrophages

Answer 10

phagocytic cells in lungs

Question 11

what is the line of defense if microbes get into the small intestine?

Answer 11

pancreatic enzymes, bile, intestinal enzymes, gut associated lymphatic tissue(GALT)

Question 12

what is peristalsis?

Answer 12

regular shedding of columnar epithelial cells
- purges intestinal microbiota

Question 13

Why is the GI tract unfavorable for microbes?

Answer 13

• flushing action
• Low pH of urine
  -Urea and other metabolic products
  for men: distance barrier
  for women: vagina is acidic because of Lactobacillus spp. as well as mucous membrane

Question 14

what are the chemical mediators in innate resistance?

Answer 14

Lysozyme- hydrolyzes bond of bacterial cell wall (harms gram + bac. bc of thick peptidoglycan)
Lactoferrin- similar to transferrin in blood, which competes for iron, limiting the growth of microbes bc they don’t have iron.

Question 15

what are the cationic peptides?

Answer 15

cathelicidins, Defensins, and Histatins

Question 15

Cathelicidins

Answer 15

linear, a-helical peptides

Question 16

Defensins

Answer 16

a defensins- smaller and found in intestinal Paneth cells, and intestinal and resp. epithelial cells
B defensins- found in epithelial cells and stimulate release of chemical mediators

Question 17

Histatins

Answer 17

Larger peptides found in saliva
Compromise mitochondrial function and generate oxidative and osmotic stress resulting in fungal death

Question 18

Bacteriocins

Answer 18

toxic peptides produced by normal microbiota, kill closely related species

Question 19

Opsonins

Answer 19

proteins that coat the cell membrane
- promotes recognition by phagocytic cells

Question 20

what are the three main functions of the Adaptive immune system?

Answer 20

1. Recognize anything foreign
2. Defend the host
   - T and B lymphocytes activated
   - effector response (eliminates or renders foreign material harmless)
3. Remember foreign invader
   - memory cells

Question 21

What are the 5 characteristics of adaptive immunology?

Answer 21

1. Discrimination
2. Specificity (T and B respond to specific non-self antigen)
3. Diversity
4. Timing
5. Memory

Question 22

Antibody-mediated (Humoral) immunity

Answer 22

B cells act and circulate antibodies that bind microbes, toxins, and viruses to neutralize or kill them

Question 23

Cell-mediated (Cellular) immunity

Answer 23

based on actions of specific T lymphocytes
-Cytotoxic T Cell (CTL)- attack target cells infected w/ intracellular pathogens
- T helper cells- direct CTL to target cell lysis