Module 2: Lecture 3

Question 1

what is a leukocyte?

Answer 1

a white blood cell

Question 2

what gives RBCs their pigment?

Answer 2

the heme group

Question 3

what is the pigment in WBC?

Answer 3

none; they are colourless

Question 4

what is the mobile unit of the bodys immune system?

Answer 4

white blood cells; leukocytes

Question 5

in general, what is a system?

Answer 5

• organs. tissues, cells are all involved
• proteins, secretions
• work together and communicate and help each other

Question 6

• what is an immune system?

Answer 6

• • made up of leukocytes, their derivatives, and variety of plasma proteins and immune organs
• protects us from invading pathogens
• recognizes and destroys or neutralizes materials within body that are foreign to “normal self”
• identifies and destroys cancer cells that arise in the body
• removes worn-out cells and tissue debris
  (wound healing and tissue repair)

Question 7

what cell in the spleen cleans up all the dead RBCs?

Answer 7

the macrophages

Question 8

the size of white blood cells is bigger or smaller than red blood cells?

Answer 8

bigger than RBCs

Question 9

there are five major types of circulating leukocytes. they vary in?

Answer 9

structure, function and number

Question 10

per mL of blood, how many leukocyte?

Answer 10

7 million/mL blood

Question 11

what are the five major different types of circulating leukocytes?

Answer 11

• neutrophils
• eosinophils
• basophils
• monocytes
• lymphocytes

Question 12

which types of leukocytes are polymorphonuclear granulocytes?

Answer 12

• neutrophils
• eosinophils
• basophils

Question 13

which types of leukocytes are mononuclear agranulocytes?

Answer 13

• monocytes
• lymphocytes

Question 14

which type of leukocytes does not have granules?

Answer 14

monocytes

Question 15

what is the most abundant type of circulating leukocyte?

Answer 15

1. neutrophils (60-70%)
2. lymphocyte (25-33%)

Question 16

what is the least abundant type of circulating leukocyte?

Answer 16

1. basophil (0.25-0.5%)
2. eosinophil (1-4%)

Question 17

• what does polymorphonuclear granulocytes mean?

Answer 17

polymorphonuclear - many-shaped nucleus
granulocytes - granule-containing cells

Question 18

what is a neutrophil?

Answer 18

• most abundant circulating WBC
• PHAGOCYTE!
• phagocytic specialist (specifically bacteria)
• has ONE nucleus with MANY SHAPES
• engulf and destroy bacteria intracellularly

Question 19

which circulating white blood cell is the MOST MOST abundant?

Answer 19

neutrophil

Question 20

which circulating white blood cell is the LEAST LEAST abundant?

Answer 20

basophil

Question 21

what does granules contain?

Answer 21

lots of toxic substances

Question 22

how are granules used in regards to neutrophils?

Answer 22

they release toxic substances when neutrophils engulf bacteria to destroy and damage the bacteria. HOWEVER, they also destroy and damage the cell so the cell will also die. the chromatin (DNA) is then released into the extracellular space (N.E.T.s)

Question 23

when DNA is thrown into extracellular space after a neutrophil dies (N.E.T.s), what happens?

Answer 23

the bacteria sticks to the DNA which will have the toxic granules which will kill the bacteria as well
OR
the bacteria sticks to the DNA and then other phagocytes will come and destroy it

Question 24

the release web of extracellular fibers that contain bacteria-killing chemicals are called what?

Answer 24

neutrophil extracellular traps (NETs)

Question 25

what are eosinophils good for?

Answer 25

killing parasites - killing of antibody coated parasites through release of granule contents

Question 26

is an eosinophil a phagocyte?

Answer 26

no. it attached to the surface of the parasite(only if it is coated with antibodies) and release its granules

Question 27

how does an eosinophil know what parasite to go to?

Answer 27

has to be a special kind of antibody coating that is specific to a parasite

Question 28

* increase in circulating eosinophils (eosinophilia) is associated with?

Answer 28

- allergic conditions such as asthma and hay fever - internal parasite infestations, such as worms (attach to worm and secrete substances to kill it)

Question 29

what is the main function of basophils?

Answer 29

- fight parasitic infections - also synthesize special chemicals that eosinophils don't do (histamines and heparin)

Question 30

which leukocyte is the least numerous and most poorly understood?

Answer 30

basophils

Question 31

what special chemicals does basophil synthesize and store?

Answer 31

histamine: release is important in allergic reactions heparin: speeds up removal of fat particles from blood after fatty meal

Question 32

what is a monocyte?

Answer 32

- mononuclear agranulocytes leukocyte - phagocyte - largest circulating immune cell - can eat larger numbers of bacteria

Question 33

what can monocytes produce?

Answer 33

- many other proteins called cytokines (cell movement)

Question 34

what can cytokines do?

Answer 34

can kill a pathogen directly or can activate another immune cell

Question 35

what do monocytes do if they are called upon a tissue?

Answer 35

they change and mature into macrophages

Question 36

what will allow a monocyte to live longer?

Answer 36

if it becomes a macrophage

Question 37

what will make a monocyte die sooner?

Answer 37

if it gets activated and start eating bacteria

Question 38

what are generally the first cells that are alerted to an infection?

Answer 38

macrophages

Question 39

what happens when there is an invading microorganism?

Answer 39

tissue resident macrophages are the first to sense invading microorganisms --> secrete cytokines/chemokines --> recruit neutrophils and other leukocytes

Question 40

what are the two types of lymphocytes?

Answer 40

1. Large Granular Lymphocytes 2. Small lymphocytes of adaptive immune response (two more types of these)

Question 41

what are the natural killer (NK) cells?

Answer 41

large granular lymphocytes

Question 42

what do NK cells do?

Answer 42

extremely good at killing virally infected cells - not adaptive or advanced - they will kill any cell that seems stressed - release lytic granules to kill the cell

Question 43

the small lymphocytes are apart of?

Answer 43

the adaptive immune response

Question 44

true or false: we have many small lymphocytes but they take a long time to become activated

Answer 44

true

Question 45

what do small lymphocytes do?

Answer 45

- they are our best immune cells (they do everything) - cytokine production - antigen recognition - antibody production - memory - cytotoxicity

Question 46

what are the two types of small lymphocytes?

Answer 46

1. B Lymphocytes 2. T Lymphocytes

Question 47

* what are B lymphocytes?

Answer 47

- type of small lymphocyte * - called humoral immunity - produce antibodies * (as a plasma cell) - responsible to anti-body mediated immunity

Question 48

what are T lymphocytes?

Answer 48

- type of small lymphocytes - called cell-mediated immunity - do not produce antibodies - directly destroy specific target cells (like cancer cells or virally infected cells) by releasing chemicals that punch holes in the victim cell - target cells include body cells invaded by viruses and cancer cells - the commanders

Question 49

which immune cell is the "general" (captain) if the immune response?

Answer 49

T Lymphocytes - they make cytokines to tell macrophages what to do - they command everything

Question 50

* all blood cells ultimately originate from same undifferentiated ________ ___________ _____ ____ in red bone marrow

Answer 50

pluripotent hematopoietic stem cells

Question 51

where are granulocytes and monocytes produced?

Answer 51

ONLY in bone marrow

Question 52

total number of white cells and percentage of each type may vary considerably to?

Answer 52

meet changing defense needs

Question 53

most new lymphocytes are actually produced how?

Answer 53

by lymphocytes already in lymphoid tissues such as lymph nodes, spleen and tonsils