Hematopoiesis

Question 1

What is HEMATOPOIESIS?

Answer 1

The formation of BLOOD CELLS

Question 2

Where does HEMATOPOIESIS occur?

Answer 2

RED BONE MARROW

Question 3

All formed elements of blood come from what CELL?

Answer 3

HEMOCYTOBLASTS (HEMATOPOIETIC STEM CELLS)

Question 4

What is LEUKOPOIESIS?

Answer 4

Formation of LEUKOCYTES (WBCs)

Question 5

What regulates LEUKOPOIESIS?

Answer 5

CYTOKINES (CELL signaling molecules) called CSFs

Question 6

Numbers of WBCs ____ and are produced in response to ______ ______ ____________

Answer 6

Vary, immune system requirements

Question 7

What is LEUKEMIA?

Answer 7

Cancer of BLOOD forming TISSUES

e.g. BONE MARROW

Question 8

What is THROMBOCYTOPOIESIS?

Answer 8

The formation of THROMBOCYTES (PLATELETS)

Question 9

What regulates THROMBOCYTOPOIESIS?

Answer 9

The hormone THROMBOPOIETIN (TPO)

Question 10

Where is THROMBOPOIETIN (TPO) produced?

Answer 10

In the kidneys

Question 11

How are PLATELETS formed?

Answer 11

Fragmentation of large CELLS called MEGAKARYOCYTES

Question 12

What is ERYTHROPOIESIS?

Answer 12

The formation of ERYTHROCYTES (RBCs)

Question 13

Approx. how long does RBC synthesis take?

Answer 13

3 - 5 days

Question 14

Approx. how many RBCs are made per second?

Answer 14

About 2 million (15 mL/day)

Question 15

Why do males have more RBCs?

Answer 15

RBC production is enhanced by steroid hormone TESTOSTERONE

Question 16

What mineral is required to make O2 carrying pigment HEMOGLOBIN (Hb)?

Answer 16

IRON (Fe)

Question 17

What is the S of HEMOGLOBIN?

Answer 17

4 GLOBIN proteins, 2 ALPHA and 2 BETA. 4 HEME molecules

Question 18

Each HEME contains a single __ (which lies within a porphyrin ring)

Answer 18

Fe

Question 19

How many O2 can each Fe bind?

Answer 19

A single one - OXYHEMOGLOBIN

Question 20

What is the max. O2 HEMOGLOBIN can carry?

Answer 20

4

Question 21

What makes CARBAMINOHEMOGLOBIN?

Answer 21

GLOBINS that bind to CO2

Question 22

What inc. RBC synthesis?

Answer 22

The GLYCOPROTEIN HORMONE ERYTHROPOIETIN (EPO)

Question 23

Where is EPO secreted?

Answer 23

From the kidneys

Question 24

When is EPO secreted?

Answer 24

In response to HYPOXIA (O2 deficient)

Question 25

HYPOXIA can be caused by these 3 things?

Answer 25

1) BLOOD loss
2) Dec. in O2 in BLOOD
3) Inc. in O2 demand

Question 26

What happens to RBCs as they age?

Answer 26

They become less flexible and more fragile, thus reducing the O2 carrying capacity and HEMOLYSIS

Question 27

What is the avg. lifespan of a RBC?

Answer 27

120 days

Question 28

Which organs trap old RBCs?

Answer 28

The SPLEEN and LIVER

Question 29

MACROPHAGES in SPLEEN and LIVER ___________ RBCs

Answer 29

phagocytize