Hematopoiesis

Question 1

what is hematopoiesis

Answer 1

formation of blood cells

Question 2

what is a hemocytoblast

Answer 2

stem cell that differentiates into all formed elements of blood

Question 3

what is leukopoiesis

Answer 3

formation of leukocytes

Question 4

what is leukopoiesis regulated by

Answer 4

cytokines

Question 5

what are cytokines

Answer 5

cells signalling molecules called colony stimulating factors (varies in response to immune system)

Question 6

what is thrombocytopoiesis

Answer 6

formation of thrombocytes

Question 7

what is erythropoiesis

Answer 7

formation of RBC

Question 8

How long does it take to make an RBC

Answer 8

3-5 days

Question 9

how many new ones are made a day

Answer 9

2 million a second (15ml a day)

Question 10

what does testosterone do to RBC production

Answer 10

enhances RBC production

Question 11

What mineral does erythropoiesis require

Answer 11

iron

Question 12

what is inside a hemoglobin (hb)

Answer 12

• globin proteins: 2 Alpha, 2 Beta

- 4 hemes with iron inside a porphyrin ring

Question 13

How many O2 and CO2 can each hb bind

Answer 13

4 O2, 4 CO2

Question 14

What controls erythropoiesis

Answer 14

a glycoprotein called erythropoietin (EPO)

Question 15

Where is EPO secreted from

Answer 15

kidneys

Question 16

why is EPO secreted

Answer 16

in response to hypoxia

Question 17

what are the 3 reasons for hypoxia

Answer 17

Blood loss
decreased O2 in blood
increased demand of O2

Question 18

What happens to RBCs w/ age

Answer 18

• less flexible & fragile

- Reduced O2 carrying capability

Question 19

What is a RBC lifespan

Answer 19

120 days

Question 20

What is the liver and spleens role in recycling RBCS

Answer 20

they trap the old ones

Question 21

What is the role of macrophages in the liver and spleen

Answer 21

they phagocytic RBC in liver and spleen to recycle RBC

Question 22

1st step of all hematopoiesis?

Answer 22

Hemocytoblast!

Question 23

Explain the pathway for thrombocytopoiesis

Answer 23

1) Hemocytoblast
2) myeloid stem cell
3) Megakaryocyte
* Fragmentation
4) Platelet!

Question 24

Explain the pathway for granulated leukopoiesis

Answer 24

1) Hemocytoblast
2) myeloid stem cell
3) Blast cells (committed cells)
4) progranulocyte
5) 3 different myelocytes
6) 3 different band cells
7) Basophil, eosinophil, neutrophil

Question 25

Explain the pathway for monocyte leukopoiesis

Answer 25

1) Hemocytoblast 2) myeloid stem cell 3) myleoblast ** different from the granulated 4) Monocyte

Question 26

Explain the pathway of erythropoiesis

Answer 26

1) Hemocytoblast 2) Myeloid stem cell 3) Proerythroblast 4) erythroblast Phase 1: ribosome synthesis Phase 2: hb synthesis 5) Normoblast phase 3: nucleus ejected 6) Reticulocyte (Young erythrocyte in circulation) 7) Erythrocyte

Question 27

Explain leukopoiesis of lymphocytes

Answer 27

1) Hemocytoblast 2) lymphoid stem cell 3) Lymphoblast 4) Lymphocyte (T or B)

Question 28

During hb recycling in liver & Spleen: what is the globin broken down into

Answer 28

Amino acid - it then enters circulation

Question 29

During hb recycling in liver & Spleen: what is the heme first broken down into

Answer 29

1) Biliverdin (green) | 2) iron

Question 30

During hb recycling in liver & Spleen: what happens to the iron?

Answer 30

1) it is bound to transferrin for transport in blood | 2) It is taken to either the liver + spleen again or bone marrow

Question 31

During hb recycling in liver & Spleen: what happens to the iron in the liver/ spleen

Answer 31

Stored as ferritin & hemosiderin

Question 32

During hb recycling in liver & Spleen: what happens to the iron that goes into bone marrow

Answer 32

it is used in erythropoiesis

Question 33

During hb recycling in liver & Spleen: what happens to the billiverdin?

Answer 33

it becomes bilirubin (yellow)

Question 34

how is bilirubin transported

Answer 34

conjugated to protein albumin

Question 35

what is bilirubin

Answer 35

part of bile, made by liver and put into small intestine to help break down food

Question 36

During hb recycling in liver & Spleen: what happens to the bile?

Answer 36

it is metabolized by bacteria in the lrg intestine and

Question 37

During hb recycling in liver & Spleen: what does the bile break down into

Answer 37

Urobilins & sterocobilins

Question 38

What color are urobilins

Answer 38

yellow

Question 39

what color are sterocobilins

Answer 39

brown

Question 40

which is found in urine

Answer 40

just urobillins

Question 41

which is found in stool

Answer 41

urobilins and stercobilins