Haematopoiesis

Question 1

What is haematopoiesis?

Answer 1

Differentiation process that forms all blood cells from haematopoietic stem cells

Question 2

Where does haematopoiesis occur in the fetus?

Answer 2

In the yolk sac then spleen and liver

Question 3

Where does haematopoiesis occur in children?

Answer 3

All bone marrow

Question 4

Where does haematopoiesis occur in adults?

Answer 4

Bone marrow of cranium, pelvis, ribs, vertebrae

Question 5

What are examples of intracellular help for stem cell growth?

Answer 5

Macrophages, fibroblasts, fat cells

Question 6

The bone marrow environment supports stem cell growth. True or false?

Answer 6

True

Question 7

What are two functions of pluripotent haematopoetic stem cells?

Answer 7

They self renew

They differentiate into a variety of cells

Question 8

What determines the growth path of pluripotent haematopoietic stem cells?

Answer 8

The growth factors that are present

Question 9

What does GM- CSF cause pluripotent haematopoietic stem cells differentiate to?

Answer 9

Granulocytes, macrophages

Question 10

What does erythropoietin induce production of?

Answer 10

RBC

Question 11

What does thrombopoietin induce production of?

Answer 11

Megakaryocytes (platelets)

Question 12

Which cytokine supports a wide range of stem cells?

Answer 12

IL-3

Question 13

Which cytokine supports the production of eosinophils?

Answer 13

IL-5

Question 14

What does M-CSF induce production of?

Answer 14

Monocytes

Question 15

What does G-CSF induce production of?

Answer 15

Neutrophils

Question 16

What is granulopoiesis?

Answer 16

The production of granulocytes

Question 17

What can be seen in the circulation if granulopoiesis is hyper stimulated?

Answer 17

Band cells

Question 18

Name the 6 cell phases of granulopoiesis

Answer 18

Myeloblast
Promyelocyte
Myelocyte
Metamyelocyte
Band cell
Mature

Question 19

During granulopoiesis what happens to the cells?

Answer 19

Decrease in size
Chromatin condense
Nuclear shape changes
Accumulation of cytoplasmic granules

Question 20

Where and when is Thrombopoietin (TPO) produced?

Answer 20

Constantly by the liver

Question 21

What does TPO bind to?

Answer 21

Receptors on megakaryocytes and platelets

Question 22

When TPO binds, what happens to it’s blood concentration?

Answer 22

Reduces

Question 23

In thrombocytopenia states what happens to the circulating concentration of TPO?

Answer 23

Greatly increases

Question 24

What do megakaryocytes release?

Answer 24

Platelets

Question 25

What happens to the size of megakaryocytes as they are produced?

Answer 25

Increases

Question 26

Where And when is Erythropoietin produced?

Answer 26

Kidneys when there is low blood oxygen

Question 27

What is thrombopoiesis?

Answer 27

The production of platelets

Question 28

What is erythropoiesis?

Answer 28

Production of red blood cells

Question 29

What is a reticulocyte?

Answer 29

The last stage of red blood cell production before maturation

Question 30

In what form does the red blood cell leave the bone marrow?

Answer 30

Reticulocyte

Question 31

How are dead erythrocytes got rid of?

Answer 31

Phagocytes

Question 32

Do red blood cells have a nucleus?

Answer 32

No

Question 33

Wha does transferrin do?

Answer 33

Recycles the iron from haemoglobin in erythrocytes back to the bone marrow

Question 34

What happens to iron free haemoglobin and where?

Answer 34

Converted to bilirubin by the liver

Question 35

What does it mean if we see normoblasts in circulation?

Answer 35

Bone marrow barrier is broken

Question 36

What is cooperative binding?

Answer 36

Once one of the four chains in haemoglobin has bound to oxygen, the other chains have increased affinity to bind to oxygen.

Question 37

What are two examples of why haemoglobin would have a decreased binding of oxygen (greater release)?

Answer 37

Low PH | Increased temperature

Question 38

What is thrombocytopenia and what could cause it?

Answer 38

Low platelet concentration in blood. Due to infection, drug, immune mechanism

Question 39

What is thrombocytosis and what could cause it?

Answer 39

Excessive number of platelets in the blood, caused by iron deficiency, inflammation, cancer, infection

Question 40

What is anaemia?

Answer 40

Reduction of haemoglobin concentration

Question 41

What is a microcytic red blood cell?

Answer 41

Low mean cell volume (very small RBC )

Question 42

What is a macrocytic rbc?

Answer 42

Rbc with high mean cell volume (large rbc)

Question 43

What is the difference between a hypochromic rbc and a hyperchromic rbc?

Answer 43

Hypo- large area of pallor | Hyper- small area of pallor

Question 44

What are the characteristics of iron-deficiency anaemia and symptoms?

Answer 44

Hypochromic, microcytic. Low Hb Target cells and pencil shaped cells Brittle nails, pallor of mucous membranes

Question 45

What is the cause of megaloblastic anaemia?

Answer 45

Haematopoiesis disorders due to vitamin b12 deficiency or folic acid deficiency

Question 46

What are the two main causes of haemolytic anaemia?

Answer 46

Immune disorder | Drug induced