Physiology Exam 5 - Immune System

Question 1

Immunology

Answer 1

study of the structure and function of the immune system

Question 2

What are the functions of the immune system?

Answer 2

• protection against infection (viruses and microbes (bacteria, fungi, and parasites))
• isolate and remove foreign substances that are not microbial
• destroy cancer cells (immune surveillance)

Question 3

What are leukocytes?

Answer 3

white blood cells

Question 4

What are the different types of leukocytes?

Answer 4

• neutrophils
• eosinophils
• basophils
• lymphocytes
• monocytes

Question 5

What are the granulocytes?

Answer 5

neutrophil, eosinophil, and basophil

Question 6

What are the agranulocytes?

Answer 6

monocyte and lymphocyte

Question 7

Neutrophils

Answer 7

• 60-70%
• barely visible granules
• 3-5-lobed nucleus

Question 8

Eosinophils

Answer 8

• 2-4%
• large granules and bilobed nucleus

Question 9

Basophils

Answer 9

• less than 1%
• large, abundant, violet granules
• s-shaped nucleus

Question 10

Lymphocytes

Answer 10

• 25-33%
• variable bluish cytoplasm
• ovoid/round, uniform dark violet nucleus (over 95% of cell)

Question 11

Monocytes

Answer 11

• 3-8%
• usually largest white blood cell
• ovoid, kidney, or horseshoe-shaped nucleus

Question 12

What does/can a monocyte turn into?

Answer 12

a macrophage

Question 13

What is leukopoiesis?

Answer 13

formation of WBCs where hematopoietic stem cells differentiate into colony-forming units

Question 14

What do the colony-forming units of white blood cells produce?

Answer 14

• myeloblasts (precursor for neutrophils, eosinophils, and basophils)
• monoblasts (precursor for monocytes)
• lymphoblasts (precursor for lymphocytes)

Question 15

How many lines of defense are there against pathogens?

Answer 15

three

Question 16

What is the first line of defense against pathogens?

Answer 16

skin and mucous membranes

Question 17

What is the second line of defense against pathogens?

Answer 17

innate immunity

Question 18

What is the third line of defense against pathogens?

Answer 18

adaptive immunity

Question 19

How does the skin act as a defense?

Answer 19

• keratin is tough
• acid mantle: film of lactic acid and fatty acids from sweat and sebum that inhibits bacterial growth
• peptides in skin kill microbes

Question 20

How do mucous membranes act as a denfense?

Answer 20

• includes digestive, respiratory, urinary, and reproductive tracts
• mucus physically traps microbes
• lysozyme: enzyme that destroys bacterial cell walls

Question 21

What does the innate immunity do as a denfense?

Answer 21

contains:
- leukocytes and phagocytic cells
- antimicrobial plasma proteins
- natural killer cells

produces:
- inflammation
- fever

Question 22

What does the adaptive immunity do as a defense?

Answer 22

contains:
- T cells and B cells
- Antigen-presenting cells (APC)

Question 23

What is innate immunity?

Answer 23

local fast response, nonspecific, lacks memory

Question 24

What is adaptive immunity?

Answer 24

slow response (1st time) and enacts memory

Question 25

What is the function of neutrophils?

Answer 25

wander in connective tissue killing bacteria by: - degranulation - phagocytosis

Question 26

What is the function of eosinophils?

Answer 26

found especially in mucous membranes - guard against parasites and allergens

Question 27

What is the function of basophils?

Answer 27

secrete chemicals and aid in the mobility and action of other leukocytes

Question 28

What chemicals do basophils secrete?

Answer 28

- leukotrienes: activate and attract neutrophils and eosinophils - histamine: a vasodilator, which increases blood flow - heparin: inhibits clot formation that would impede leukocyte mobility

Question 29

What is the concentration of lymphocytes in the blood?

Answer 29

- 80% T cells - 15% B cells - 5% natural killer cells

Question 30

What is the function of natural killer cells?

Answer 30

attack and destroy bacteria, transplanted cells, cells infected with viruses, and cancer cells

Question 31

What is the function of monocytes?

Answer 31

emigrate from that blood into connective tissues and transform into macrophages

Question 32

What are macrophages?

Answer 32

all of the body's avidly phagocytic cells

Question 33

What is the function of wandering macrophages?

Answer 33

actively seek pathogens (widely distributed in loose connective tissue)

Question 34

What is the function of fixed macrophages?

Answer 34

phagocytize pathogens that come to them

Question 35

What are examples of fixed macrophages?

Answer 35

- microglia: in CNS - alveolar macrophages: in lungs - stellate macrophages: in liver

Question 36

What are antimicrobial proteins?

Answer 36

- proteins that inhibit microbial reproduction - provide short-term, innate immunity to pathogenic bacteria and viruses

Question 37

What are the two families of antimicrobial proteins?

Answer 37

interferons and complement system

Question 38

What is the function of interfeurons?

Answer 38

- the alerted cell synthesizes various proteins that defend it from infection (breaks down viral genes or prevents replication) - activates NK cells and macrophages (destroy infected cell before they can liberate a swarm of newly replicated viruses and activated NK cells destroy malignant cells)

Question 39

What is the complement system?

Answer 39

a group of 30 or more globular proteins that contribute to both innate immunity and adaptive immunity - synthesized mainly by the liver - circulate the blood in inactive form - activated by presence of a pathogen

Question 40

What are the three pathways for complements?

Answer 40

classical pathway, alternative pathway, and lectin pathway

Question 41

What are the four methods of complement pathogen destruction?

Answer 41

- inflammation - immune clearance - phagocytosis - cytolysis

Question 42

What are the three main characteristics of adaptive immunity?

Answer 42

- systemic effect: throughout the body - specificity: immunity is directed against a particular pathogen - memory: when re-exposed to the same pathogen, the body reacts so quickly that there is no noticeable illness