Cells of the blood Flashcards
Function of circulatory system
Pumps blood around body
Functions of blood
Distributes substances around body
Maintains temperature
Maintains pH
Prevents infection
What happens when you centrifuge blood?
Densest section = erythrocytes
Least dense is plasma
The two are separated by Buffy coat
What is the buffy coat?
White layer containing platelets and leukocytes
What are erythrocytes?
RBCs
What are leukocytes?
WBCs
What is plasma?
Sticky fluid
Mostly water
Some proteins/nutrients/ions etc
2 examples of proteins found in plasma
Albumin
Globulins
What does albumin do?
Contributes to osmotic pressure
What do globulins do?
Binds to molecules for transport
Characteristics of red blood cells?
No cell division Numerous Bi-concave Anucleate Lots of hemoglobin
How are RBCs and platelets replaced?
Stem cells in bone marrow
How many polypeptide chais make up haemoglobin?
4 - 2 alpha and 2 beta
What is each polypeptide chain in haemoglobin bound to?
A heme group with iron at the centre
How many molecules of oxygen does each haemoglobin molecule bind to?
4
What is hematopoiesis?
Making blood cells
Where does hematopoiesis occur?
Red bone marrow
Function of leukocytes
Part of immune system
Defend against pathogens
What doe neutrophils do?
Kill bacteria by phagocytosis
What do eosinophils do?
Kill parasitic worms
Combat effects of histamine in allergic reactions
What do basophils do?
Intensify inflammatory response in allergic reactions
What do lymphocytes do?
B-cells develop into plasma cells to secrete antibodies
T-cells attack viruses and cancer cells
NK cells attack infectious microbes
What do platelets do?
Fragments of megakaryocytes
Blood clotting
Why do megakaryocytes form?
Repeated mitotic cycles with no cytokinesis
Which antibodies are in the plasma of someone with blood type A?
Anti - B
Which antibodies are in the plasma of someone with blood type b?
Anti-A
Which antibodies are in the plasma of someone with blood type O?
Anti-A and Anti-B
Why are blood types normally followed by a positive or negative sign?
Rh positive or negative
Volume of blood in adult
5 litres
What is the first cell involved in haematopoeisis?
Multipoetic stem cells
Where does haumatopoeisis take place?
Red bone marrow
What does the myeloid progenitor cell do?
Makes RBCs and megakaryocytes
What do myeloblasts produce?
WBCs
How are RBCs removed?
Phagocytic macrophages in spleen and liver
What is haemolytic anaemia?
If RBC isn’t shaped correctly, it is phagocytosed by macrophages
Where does erythropoiesis take place?
Red bone marrow
What is the precursor cell for erythropoiesis?
Proerythroblast
What happens when less oxygen reaches kidneys?
They secrete erythropoietin, which increases the rate of maturation of proerythroblasts
What happens to the amount of red bone marrow you possess as you age?
Replaced by yellow marrow (mainly fat)
When can yellow marrow convert to red?
In extreme blood loss
What is the difference between macrophages and monocytes?
Same cell but macrophage in tissue and monocyte in blood
Why don’t basophils have a nucleus?
Full of granules
Why do eosinophils appear pink?
React with eosin stain
What do monocytes look like?
Large and have big nucleus shaped like a bean
Where do platelets originate?
Megakaryocytes in red bone marrow
Do thrombocytes have a nucleus?
No
Main function of platelets
Form platelet plug
Lifespan of platelets
5-9 days
What is microcytic anaemia?
Vitamin B12 deficiency - lots of reticulocytes in system increases mean cell volume
What do lots/few platelets in the blood indicate?
Infections/bleeding
What percentage of WBCs are neutrophils?
60-70
What percentage of WBCs are basophils?
0.5-1
What percentage of WBCs are eosinophils?
2-4
What percentage of WBCs are monocytes?
3-8
What percentage of WBCs are lymphocytes?
20-25
What do monocytes do?
Transform to macrophages and then phagocytose
Normal range of basophils
<0.1
Normal range of monocytes
0.2-0.8 x 10^9 per litre
Normal range of eosinophils
0.04-0.44 x 10^9 per litre
Normal range of lymphocytes
1.3-4 x 10^9 per litre
Normal range of neutrophils
2-7.5 x 10^9 per litre
Normal range of WBCs
4-11 x 10^9 per litre
Normal range of platelets
150-400 x 10^9 per litre
Normal range of RBCs for male and female
M: 4.5-6.5 x 10^12
F: 3.8-5.8 x 10^12
Normal packed cell volume for M and F
M: 0.4-0.52
F: 0.36-0.47
Mean cell haemoglobin concentration
32-36 g/dL
Normal range of mean cell haemoglobin
27-32 pg
Normal range of mean cell volume
77-95 fL
Normal haemoglobin concentration for M and F
M: 13-18 g/dL
F: 11.5 - 16.5 g/dL