6. Blood

Question 1

What are the % compositions of the blood?

Answer 1

55% plasma
44% RVC
1% WBC and platelets

Question 2

Where are erythrocytes produced and destroyed?

Answer 2

Produced in haemopoetic bone marrow
Destroyed by spleen + liver

Question 3

What are reticulocytes?

Answer 3

Immature RBC (larger and loosing nucleus) containing blue staining ribosome remenants.
Increase with severe loss of blood.

Question 4

Which WBC are granulocytes?

Answer 4

Neutrophils, Basophils, Eosiniphils

Question 5

Features of eosinophils

Answer 5

Bi or tri-lobed nucleus with crystalline inclusions and bright pink granules. They phagocytoses antigen-antibody complexes and neutralise histamine actions (restrict inflammatory response)

Question 6

Which WBC is the most and least numerous?

Answer 6

Most = Neutrophils
Least = Basophils

Question 7

Describe neutrophils

Answer 7

Multi-lobular nucleus (2-6) and most enters tissue at site of infection. Phagocytoses bacteria + worms in hostile conditions.

Question 8

What 3 granule types are found in neutrophils?

Answer 8

1. Lysosomes for phagocytosis
2. Unique to neutrophils for inflammatory response
3. Secretes enzymes to break protein + adhesion molecules

Question 9

Describe basophils

Answer 9

Bi-lobed nucleus hard to see with large blue granules appear to fill cell.

Question 10

Function of basophils (in anaphylaxis)

Answer 10

Activation of IGE receptors release histamine which results in inflammatory reactions to prevent coagulation + agglutination.

Question 11

Describe lymphocytes

Answer 11

Round, dark blue nucleus with thin rim of paler cytoplasm. Circulates in blood but works within lymph nodes and connective tissue of organs.

Question 12

Give the functions of all the different lymphocytes

Answer 12

B-cells
T-helper cells
T-cytotoxic cells
T-suppressor cells
Natural killer cells

Question 13

Functions of monocytes

Answer 13

Immature circulating form differentiates into tissue macrophages, kupffer cells (liver), osteoclasts (remodels bone), antigen presenting cells and alveolar macrophages (lungs).

Question 14

Describe platelets

Answer 14

Small fragments of cells derived from Megakaryocytes in bone marrow. Of blue colouration, without a nucleus and is important in homeostasis.

Question 15

What are the 3 types of granules in platelets?

Answer 15

1. Alpha contain clotting factors
2. Delta contain serotonin absorbed after clotting factors discharged
3. Peroxisomes catalyse elimination of O2 radicals

Question 16

Describe the 3 different types of homeopoatic stem cells

Answer 16

Myelin- Next to bone forms wbc
Erythron- Next to bony trabeculae forms rbc
Megakaryocytes- Next to bony trabeculae forms platelets

Question 17

What is the precursor cell in homeostasis

Answer 17

Multi potential homeopoietic stem cell (hemocytoblasts)

Question 18

Describe Enthrypoesis

Answer 18

Proerythroblast becomes smaller, looses nucleus and produces haemoglobin to become a RBC

Question 19

Describe granulopoesis

Answer 19

Myeloblast increases number of granules and complex shape of nucleus to form neutrophils, eosiniphils and basophils.

Question 20

Erythrocyte structure

Answer 20

Anucleate, bi-concave , spectrum proteins