Lecture 26- Blood/Immunity

Question 1

Plasma

Answer 1

Pale yellowish, many components
Mostly H2O
Salts-dissolved ions
Osmotic balance
Composition of interstitial fluid

Question 2

Function of plasma proteins

Answer 2

Regulate fluid in plasma vs. interstitial fluid

Question 3

Albumins

Answer 3

Plasma proteins that regulate pH, osmotic balance

Question 4

Immunoglobulins

Answer 4

Plasma proteins that are antibodies- defense

Question 5

Apolipoproteins

Answer 5

Plasma proteins that do lipid transport

Question 6

Fibrinogens

Answer 6

Plasma proteins that do clotting (serum= plasma w/o fibrinogens)

Question 7

Substances transported in plasma

Answer 7

Nutrients
Wastes (CO2)
Gases (O2)
Hormones

Question 8

Where/how is blood produced?

Answer 8

Bone marrow
Multipotent stem cells divide -> one stays stem, one specializes
Ribs, vertebrae, sternum, pelvis

Question 9

What are the three groups of blood cells?

Answer 9

Red blood cells- erythrocytes
White blood cells- leukocytes
Platelets

Question 10

Erythrocytes

Answer 10

Red blood cells (RBCs)
Most numerous
Flexible biconcave discs
No nuclei- more space for hemoglobin
No mitochondria- anaerobic metabolism
Specialized for O2 transport (O2 insoluble in aqueous solutions)
Hemoglobin

Question 11

Leukocytes

Answer 11

White blood cells (WBCs)
Specialized for defense against pathogens
Not confined to circulatory system- interstitial fluid, lymph nodes

Question 12

Platelets

Answer 12

Not whole cells- Formed via pinching fragments of large cells in bone marrow
No nuclei
Involved in clotting

Question 13

Platelet Plug Formation

Answer 13

Temporary clot
Blood vessel damaged
-> Vessel constricts
-> Platelets stick to collagen fibers
-> Platelets release attractants
-> More platelets stick

Question 14

Fibrin Clot Formation

Answer 14

Fibrin clots are stronger, permanent
30 clotting factors involved
From platelets, damaged cells, plasma

Clotting factors, calcium, platelet compounds are a cascade that activates prothrombin into thrombin. Prothrombin is a plasma protein from liver, requires vitamin K. Thrombin catalyzes fibrinogen (soluble) into fibrin (insoluble). Sticky, gooey fibers make a net over the break and catch platelets and red blood cells, make a big mass of cells and fibers that block the break in the blood vessel.

Question 15

Platelet plug vs. Fibrin clot

Answer 15

Platelet plug is temporary and faster, fibrin clot is slower and permanent.

Question 16

Hemophilia

Answer 16

1 clotting factor missing or defective

Question 17

Anticlotting Factors and thrombus

Answer 17

Prevent spontaneous clotting in the absence of damage
Thrombus- clot within blood vessels, can block flow

Question 18

Purpose of immune system

Answer 18

Protects against pathogens, foreign molecules

Question 19

What are the two types of defense systems?

Answer 19

Innate immunity and adaptive immunity

Question 20

Adaptive Immunity

Answer 20

Acquired immune response
Specific response to specific antigens

Question 20

Innate Immunity

Answer 20

General protection against pathogens

Question 21

Barrier Defenses

Answer 21

Innate immunity
Non-specific “anatomical” barriers
- Prevent entrance
- Physical and chemical

Question 22

Examples of Barrier Defenses

Answer 22

Skin (integumentary system)- Not penetrable by bacteria, viruses
- Habitat for commensal bacteria
- Chemical barrier- oil and sweat glands- pH 3-5

Mucous lining- Mucus is viscous, traps pathogens
- Digestive, urinary, respiratory, reproductive tracts
- Ciliated epithelial cells
Lysozyme: destroy bacterial cell walls

Stomach
Pathogens ingested-> destroyed by stomach acid

Question 23

Cellular Innate Defenses

Answer 23

Destroy pathogens that get in

Question 24

What are the two types of Cellular Innate Defenses?

Answer 24

Phagocytic cells and Natural Killer cells

Question 25

Phagocytic cells

Answer 25

Ingest pathogens via phagocytosis Often found in lymphatic system- lymph nodes during infection Have Toll-like receptors (TLR) - Bind molecules characteristic of pathogens, absent from vertebrates

Question 26

Phagocytic Cell Activity-SEQ process of phagocytic cells

Answer 26

1. Pseudopodia surround pathogens 2. Pathogens engulfed by endocytosis 3. Vacuole forms 4. Vacuole and lysosome fuse 5. Pathogens destroyed 6. Debris from pathogens released

Question 27

Natural Killer (NK) Cells

Answer 27

Circulate through body Recognize abnormal surface proteins- indicate virus infection, cancer Release chemicals- trigger cell death Do not directly attack pathogens

Question 28

Interferons

Answer 28

Secreted by virus-infected cells Do not save infected cell, help other resist infection

Question 29

Complement system

Answer 29

30 proteins in plasma Circulate inactive- activated by surface proteins of microbes -> lysis of invading cells

Question 30

Local Inflammatory Response

Answer 30

Activated by tissue damage-> heat, redness, edema, pain Histamines + cytokines released, capillaries dilate WBCs recruited, antimicrobial peptides released Pathogens digested, tissue heals

Question 31

General Inflammatory Response

Answer 31

Inflammation can involve whole body -> Fever: Change in set point temp of body to facilitate immune response - Raises body temp - Increases phagocytosis - Interferes with pathogens