Blood And Haemopoeisis

Question 0

What happens in differentiation in haemopoiesis?

Answer 0

A haemopoietic progenitor will first differentiate to form either a myeloid blast or a lymphoid blast.

Question 1

What happens in proliferation in haemopoiesis?

Answer 1

A stem cell divides into two, one to replace the original stem cell (self renewal) and the other that differentiates

Question 2

What influences what the progenitor will differentiate into? Give an example

Answer 2

A cytokine.
Eg erythropoietin will produce red blood cells
Thrombopoietin will produce platelets.

Question 3

What will a myeloid blast go onto form?

Answer 3

A red blood cell, white blood cell or platelets.

Question 4

What will a lymphoid blast go onto form?

Answer 4

Immunoresponse cells

Question 5

Name the five types of white blood cells

Answer 5

Neutrophil
Eosinophil
Lymphocyte
Monocyte 
Basophil

Question 6

What is the function of neutrophils?

Answer 6

They migrate out of bloodstream to the site of infection (chemotaxis)
Phagocytosis
Increase the production of G-CSF

Question 7

What do eosinophils do?

Answer 7

Phagocytosis of antigen-antibody complexes
Release cytotoxic enzymes to damage larger particles
Mediate hypersensitivity reactions - asthma, skin inflammation

Question 8

What do basophils do?

Answer 8

Mediate acute inflammatory responses using heparin, histamine and serotonin

Question 9

What do monocytes do?

Answer 9

Migrate to become macrophages in many organs of the body

Capable of phagocytosis and interact with T cells

Question 10

Which type of white blood cell has a multi-lobed nucleus?

Answer 10

Neutrophil

Question 11

How is erythropoiesis regulated?

Answer 11

Reduced pO2 detected in kidney
Stimulates production of erythropoeitin
This stimulates maturation and release of RBCs from bone marrow
Haemoglobin rises

Question 12

What do lymphocytes do?

Answer 12

Those with CD4 on their surface - helper cells
Recognise antigens and stimulate T suppressor cells
Allow transformation of plasma cells to B cells

Those with CD8 - T suppressor cells
Recognise and kill virally infected cells.

B lymphocytes responsible for humoral immunity
Stimulated by antigens to transform into immunoblasts and then plasma cells, which secrete immunoglobulin

Question 13

What do eosinophils look like?

Answer 13

Orange granules

Bi-lobed nucleus

Question 14

What do basophils look like?

Answer 14

Have many dark purple granules

Question 15

What do lymphocytes look like?

Answer 15

Small
Round nucleus
Pale rim of cytoplasm

Question 16

What is the structure of an erythrocyte?

Answer 16

Bi concave disc
4 globulin chains (2 alpha, 2 beta)
Each molecule carries a haem

Question 17

What is the function of an erythrocyte?

Answer 17

Carry oxygen to tissues and carry carbon dioxide to the lungs

Question 18

What are reticulocytes?

Answer 18

Newly formed red blood cells which have only just been discharged into the blood from bone marrow

Question 19

What are platelets produced by?

Answer 19

Megakaryocytes in the bone marrow

Question 20

What does the cytoplasm of platelets contain?

Answer 20

Alpha granules - fibrinogen and von Willbrand’s clotting facto
Dense granules - ADP and calcium

Question 21

What is on a platelet’s phospholipid surface?

Answer 21

Binding sites for clotting factors during activation of the clotting cascade.