Blood and Immunity

Question 1

blood composition

Answer 1

• Red Blood cells (erythrocytes) take up 45%
• WBCs (leukocytes) take up <1%
• platelets <1%
• plasma 55%

Question 2

blood plasma

Answer 2

• 90-92% water
• contains electrolytes and glucose
• clotting factors
• plasma proteins (7%)
• serum is plasma without clotting factors

Question 3

RBCs

Answer 3

• live around 120 days
  -30 trillion
• replace 1% per day
• need: iron B12,erythropotent from kidney (released when blood O2 is low)

Question 4

neutrophils

Answer 4

• 60-70% of all WBCs
• phagocytes

Question 5

monocytes

Answer 5

• 2-8% of WBCs
• macrophages

Question 6

Eosinophils

Answer 6

• 1-4% of WBCs
• allergy response

Question 7

Basophils

Answer 7

• <1% of WBCs
• histamine

Question 8

Lymphocytes

Answer 8

• 20-30% ofWBCs
• T cells and B cells

Question 9

Platelets

Answer 9

• cell fragments needed for clotting
• lifespan of 5-9 days

Question 10

blood clotting

Answer 10

• vascular spasm/ vasoconstriction to reduce blood loss
• platelet plug: exposure to collagen activates platelets, surrounding healthy tissues inhibit platelets
• coagulation: formation of fibrin threads

Question 11

what dies blood clotting require

Answer 11

-clotting factors
- platelets
- calcium
- vitamin K (for formation of several factors)

Question 12

paths for coagulation

Answer 12

• extrinsic path: needs external factor
• initiated first
• intrinsic path: slower, more fibrin
• triggered through positive feedback

Question 13

bacteria

Answer 13

• small cells that often rely on tissues for food
• antibiotics only work on bacteria bc they have a cell membrane

Question 13

viruses

Answer 13

• DNA plus a protein coat
• cannot replicate themselves, instead they infect cells to replicate

Question 14

fngi

Answer 14

• plant like organisms larger than bacteria
• inflammation response

Question 15

nonspecific resistance (innate immunity)

Answer 15

• present at birth and includes defense mechanism against a wide range of pathogens
• external defenses, inflammation, interferon, natural killer cells, phagocytes, compliment system

Question 16

Specific immunity (adaptive immunity)

Answer 16

• involved activation of specific lymphocytes hat combat a particular pathogen or other foreign substance
• T-cells: kill infected cells
• B-cells: antibody response

Question 17

first line of defense

Answer 17

• skin and mucous membrane

Question 17

second line of defense

Answer 17

• non specific mechanisms
• phagocytosis, NK cells, inflammation, fever

Question 18

third line of defense

Answer 18

• specific defense

Question 19

Inflammation responce

Answer 19

• cytokines from injury cause mast cells to release histamine
• histamine causes:
  ↑ blood flow to site (red, hot)
  ↑ Permeability of capillaries
  ↑ WBC’s/proteins to site
  ↑ Fluid follows

Question 20

interferon

Answer 20

• cytokine from infected cell
• prevents infection of other cells

Question 21

B-cells

Answer 21

• specific immunity
• attack free virus
• antibody reaction
• antibodies bind to antigens and mark them for destruction by phagocytes and compliment system

Question 22

B lymphocytes

Answer 22

• bind to antigen and become activated by helper T cells and cytokines
• divide and differentiate into
• plasma cells: secrete antibodies
• memory cells: stronger second response

Question 23

helper t cells

Answer 23

secrete cytokines
- meditates fever
- increases amount of B and T cells
- necessary for strong response

Question 24

cytotoxic T cells

Answer 24

• directly attack infected cells
• recognize antigen marker

Question 25

suppressor T cells

Answer 25

• limits response