W4: Haematopoiesis

Question 1

sites of Blood Cell Production

Answer 1

BM

Question 2

BC maturation

Answer 2

BM + thymus

Question 3

BC function

Answer 3

O2 transport - rbcs
immune defence - wbs
blood clotting - platelets

Question 4

BC destruction

Answer 4

spleen

Question 5

pos = neg selection in thymus

Answer 5

cortex = pos sel
cortex-medulla border = neg sle

Question 6

primary vs secondary lymphoid organs

Answer 6

primary - site of immune cell prod + dev
secondary - site of lymphoid maturation, Ag entrapment + BC destruction

Question 7

secondary lymphoid organs

Answer 7

lymphatic sys
spleen
MALT (mucosal associated lymphoid tissue)
peyers patch in small intestine

Question 8

lymph travel where + collects where

Answer 8

lymphatic vessels
valves = lymph nodes
collects in thoracic duct

Question 9

lymph nodes

Answer 9

submandibular
cervical
axillary
thoracic
abdominal
pelvic
inguinal

Question 10

lymph nodes = site of

Answer 10

T and B activation + division

Question 11

primary vs secondary lymphoid follicles (clusters of B cells)

Answer 11

primary = inactivated B cells
secondary = activated B cells

Question 12

germinal centres

Answer 12

clusters of proliferating B-cells +T helper cells

B cells here multiply to PLASMA CELLS + secrete Abs to fight infection

Question 13

what cells are in lymph nodes

Answer 13

lymphocytes
macrophages
dendritic cells (DCs)

Question 14

3 zones of lymph nodes + cells they contain

Answer 14

cortex - inactive B lymphocytes
paracortex - Th cells
medulla - macrophages

Question 15

spleen is site of

Answer 15

extramedullary haematopoiesis + BC prod - can be re-initiated

Question 16

spleen projections on outer capsule called

Answer 16

trabecula

Question 17

travel path of blood in spleen

Answer 17

enters via splenic artery
arteriole cords
white pulp
red pulp
re-enters circ into venous sinuses (blind ending veins)
splenic vein

Question 18

white pulp surrounds ____ forming ____ containing which cells

Answer 18

splenic artery
periarteriolar lymphoid sheath
t lymphocytes

Question 19

marginal zone of spleen contains which 2 cell types

Answer 19

B cells + macrophages

Question 20

red pulp consists of

Answer 20

splenic sinuses + splenic cords

Question 21

Mucosal associated lymphoid tissue (MALT) includes

Answer 21

tonsils
Peyer’s patches
appendix
lymphoid follicles in the intestines
lymphoid follicles in mucous membranes lining airways + genital tracts

Question 22

tonsil structure

Answer 22

meshwork of reticular cells fibres interspersed w lymphocytes, macrophages, granulocytes + mast cells

Question 23

tonsil function

Answer 23

defend against antigens entering through nasal + oral epithelial routes

Question 24

peyers patch

Answer 24

The GI tract can endocytose antigen from the lumen where an immune response can be raised and antibody can be exported to the lumen

Question 25

peyers patch (groups of lymphoid follicles) lamina propria submucosal layer M cells

Answer 25

LP - B cells, plasma cells, activated Th, macrophages SL - below LP - contains peyers patch M - (microfold cells) lack microvilli + endocytose Ag from gut lumen

Question 26

antigens in GI taken up by what cells + how + transported where

Answer 26

M cells by endocytosis + transported to lymphoid follicles

Question 27

B cells in follicles differentiate to ___ + release ___ into gut lumen

Answer 27

plasma cells IgA

Question 28

stem cells divide into

Answer 28

myeloid progenitor lymphoid progenitor

Question 29

whats CFU

Answer 29

colony forming unit = a colony of cells generated from one progenitor cell

Question 30

what are burst forming units (BFUs)

Answer 30

Burst forming units – a colony of cells that responds to erythropoietin to produce erythrocytes (in culture).

Question 31

cell lifespans of erythrocytes neutrophils t cells platelets

Answer 31

120d 2-3d 20-30yrs 7-10d

Question 31

differentiation depends on which 2 factors

Answer 31

growth factors cytokines received by progenitor cells

Question 32

Most haematopoietic growth factors are prod by BM ___ cells except for (2 things - prod where instead?)

Answer 32

stromal cells Erythorpoietin – synthesised by kidney Thrombopoietin – synthesised by liver