The Blood Flashcards
What is blood in terms of tissue types?
Liquid connective tissue
What does blood transport?
Oxygen, carbon dioxide, water, nutrients, waste products and heat
One function of blood is protection. How?
Clotting, immunity/defence and inflammation
What does the blood regulate?
Fluid, pH, temperature and others including hormones
What are the properties of blood?
Viscosity (resistance to flow) and osmolality (concentration)
On average how many litres of blood do adults have?
4-6L
What does centrifuging do?
Separates cells from plasma.
What is the haematocrit?
The percentage of total volume of blood made up of cells
What are the normal haematocrit values for males and females?
Females 37-47% and Males 40-54%
What are the contents of blood plasma?
Nutrients, gases, electrolytes, hormones, plasma proteins, waste products.
What are some of the plasma proteins?
Albumin (the most abundant), Fibrinogen, clotting factors and globulins.
Where is albumin produced?
The liver
Where is fibrinogen and clotting factors produced?
The liver
Where are globulins produced?
Plasma cells
What is the other name for red blood cells?
Erythrocytes
What is the role of erythrocytes?
Gas transport (oxygen and carbon dioxide)
Why are erythrocytes disc shaped?
To increase surface area: volume ratio
Do erythrocytes have a nucleus and organelles?
No
What is the average life span of an erythrocyte?
120 days
What enzyme is inside erythrocytes?
Carbonic anhydrase
What does carbonic anhydrase do?
Produces carbonic acid from carbon dioxide and water
How many haem groups/protein chains are there a haemoglobin?
4
Each globin chain of haemoglobin contains haem with Fe2+ to…
Bind oxygen
How does foetal haemoglobin differ from adult haemoglobin in terms of affinity for oxygen?
The foetal haemoglobin has a higher affinity for oxygen
What are the normal ranges for red cell count for both men and women?
3.8-5.8 for women and 4.5-6.6 for men
What is erythrocyte sedimentation rate?
The time it takes for RBC’s to settle.
Erythrocyte sedimentation rate is increased by…
Cancer, rheumatoid arthritis, kidney disease and severe/chronic infection
What is the other name for white blood cells?
Leukocytes
There are two types of leukocytes (WBC’s), what are they?
Granulocytes and Agranulocytes
There are 3 types of granulocytes, what are they?
Neutrophils, eosinophils and basophils
There are 2 types of Agranulocytes, what are they?
Lymphocytes and monocytes
When would neutrophils increase in number?
During bacterial infections e.g. appendicitis and haemorrhage – phagocytosis
When would eosinophils increase in number?
During parasitic infections or allergies such as asthma, hayfever, tapeworm and hook worm infections
When would basophils increase in number?
During chickenpox, sinusitis, diabetes and haemolytic anaemia.
When would lymphocytes increase in number?
During infections and immune responses to destroy foreign cells and virally infected cells
When would monocytes increase in number?
Malaria and typhoid
What do monocytes become?
Tissue macrophages
The increase of white blood cells is known as…
Leukocytosis
Name the functions of platelets
Secrete clotting factors, factors for endothelial repair and vasoconstrictors. Form temporary platelet plugs. Dissolve old blood clots. Attract WBC’s to sites of inflammation.
Which tissues can produce blood cells after birth?
Red bone marrow and lymphoid tissue
Which hormone stimulates red cell production? Where is it made?
Erythropoietin from the kidney.
Which cell types give rise to all cell types?
Stem cells
How long is the development of an erythrocyte?
3-5 days
What are reticulocytes?
Young red cells
What do macrophages in the spleen and liver do?
Digest cell components. Convert haem to bilirubin which becomes bile product in faeces.
Describe the negative feedback cycle of erythrocyte homeostasis.
Drop in RBC count leads to hypoxemia to kidneys which increases production of erythropoietin to stimulate bone marrow to increase RBC count in 3-5 days.
What can cause hypoxia?
Lung disease, smoking, high altitude, increase in exercise and bleeding.
What substances do we need for red blood cell production?
Iron, B12 and folic acid.
Where is iron stored in the body?
Liver
What is anaemia?
Problems with RBC’s or haemoglobin
What can cause anaemia?
Decrease RBC production or haemoglobin synthesis, inadequate nutrition, loss of blood, RBC destruction or something is wrong with the cells e.g. sickle cell.
