Into to structure and function of blood Flashcards
What is pathology?
Pathology is the study of suffering
What is blood made up of?
Plasma Cells: White Red Platelets
What happens to blood after centrifugation?
- Red cells at bottom of cuvette
- Plasma at top
Buffy coat in the middle (White cells)
What are red blood cells also known as?
Also known as erythrocytes
Shape of red blood cells
Biconcave discs
What do red blood cells not have?
No nucleus, DNA RNA or mitochondria
What is the major constituent in red blood cells and what does it do?
Major constituent is Hb
Hb binds oxygen and carries it from lungs to tissue
What is the average life span of RBC’s?
120 days
What is the diameter of RBC?
Diameter is 8um
What is the thickness of RBC
2um
What are white blood cells also known as?
Also known as leukocytes
What is the colour of white blood cells?
Colourless
What are the two most common white blood cells?
Two most common white blood cells:
Neutrophils
Leukocytes
Comment on the nucleus of neutrophils and what does that mean
Polymorphonuclear
Irregular, multi-lobed nucleus
What are granulocytes?
WBC which Contain granules
What are the three type of granulocytes?
Neutrophil
Eosinophil
Basophil
Neutrophils
Commonest WBC
Weakly staining granules
Eosinophil
Granules stained red with eosin
1-4% of WBC
Basophil
Granules stain blue with basic dye
<0.5% of WBC
What do mononuclear cells lack?
Lack granules
Comment on the nuclei of mononuclear cells?
Large, regular nuclei
What are the types of mononuclear cells?
Monocytes(Largest WBC)
Lymphocytes
What are platelets also known as?
Also known as thrombocytes
What type of fragments are platelets?
Cytoplasmic fragments
What do platelets not have?
No nucleus
Comment on membrane platelets
Are membrane bound
What do platelets contain?
Granules
What is the role of platelets and the steps involved?
Major role in haemostasis ○ Recognise damage at blood vessel wall ○ Form a platelet plug § Fibrinogen converted to fibrin by thrombin § Clotting factors control process § Fibrin clot reinforces primary platelet plug ○ Prevent/stop bleeding § However insecure and temporary
Where are mature blood cells produced?
Mature blood cells produces from stem cells in bone marrow
What does the bone marrow contain?
Contains many immature cells
What are some blood diseases treated by?
Some blood diseases treated by bone marrow transplantation
What is the plasma and what does it contain?
Plasma is a fluid containing: ○ Water ○ Salts ○ Proteins ○ Organic molecules: § Metabolites § Carbohydrates Lipids
What is serum?
Fluid left after blood clotting
What do some blood tests require and what is used?
• Some blood tests requires unclotted blood
Anticoagulants used like EDTA
What do other test work better than?
Other tests work better with serum than plasma
What percentage of plasma is protein?
7-9% of plasma is protein
Comment on plasma protein
Complex-Thousands of different proteins
What percentage of plasma proteins is a single protein?
But >90% is a single protein: albumin
What is the function of blood?
• Transport
• Defence
Homeostasis
What does blood carry?
Carry oxygen/nutrients to tissues
What does blood remove?
Removes CO2 from tissue
What type of substances does blood transport?
Transport substances like hormones from there site of production to their site of action
How do most erythrocytes carry CO2?
Most CO2 carried as bicarbonate in plasma
What enzyme helps with the transportation of CO2?
○ Red cell enzyme, carbonic anhydrase helps CO2
§ To dissolve in plasma in the tissues
§ Come out of solution in the lungs
What type of substances does plasma carry?
Plasma proteins carry substances which are poorly soluble in water like lipids and metal ions
What is albumin?
A general purpose carrier
Examples of specialised carriers
TBG
Transferrin
What cells are involved in immunity?
WBC and plasma protein
What cells are involved in clotting?
Platelets and plasma proteins
Types of WBC
Neutrophils Lymphocytes Eosinophils Basophils Monocytes
Neutrophils
§ Phagocytose and kill bacteria and fungi
Main mediators of innate immunity
Lymphocytes
§ Main mediators of adaptive immunity
§ Produce antibodies
Kill virus infected cells
Eosinophils
Kill parasites
Involved in allergic responses
Basophils
Kill parasites
Involved in allergic responses
Involved in inflammation
Monocytes
Phagocytosis of dead cells and pathogens
Two types of plasma-immune defence
Immunoglobins
Complement proteins
Immunoglobins
§ Made by B-lymphocytes
Act as antibodies against pathogens
Complement proteins
§ Kill bacteria and other pathogens
Cooperate with Ig and WBC
What is homeostasis?
Keeping internal environment of the body constant
What pH is maintained?
Maintaining pH at 7.4
What does homeostasis control distribution of?
Controlling distribution of water and solutes
Distributing heat
What is homeostasis disturbed by?
Disturbed by the disorders of: ○ Kidney ○ Liver ○ Lungs ○ Cardiovascular system ○ Endocrine organs
How is kidney function checked?
Kidney function checked by analysis of urea and electrolytes
What analysis is required for diagnosis and treatment?
Plasma analysis required for diagnosis and treatment
What is total blood volume?
5 litres
What is total plasma volume?
2.5-3 litres
What is haemoglobin made up of?
Made up of 2 alpha and 2 beta globin chains
What does each globin chain in Hb carry?
Each globin chain carries a haem molecule
What does haem hold?
Haem holds a Fe2+ atom
How does oxygen bind to Iron?
Oxygen binds reversibly to iron atom by coordination bond
What colour is oxyhemoglobin?
Bright red
What colour is Deoxyhaemoglobin?
Dark red
How many Hb molecules in each RBC and how much space does it take up ?
• About 300,000,000 Hb molecules in each RBC
V.high concentration taking up 50% of space in a red cell
What does pulse oximetry measure and determine?
• Measures colour of haemoglobin
Determines if patient is hypoxic
What is haematocrit also known as?
Also known as packed cell volume
How to calculate haematocrit ratio
Volume of cells/ total volume
What is the normal haematocrit value?
Normal value about 0.4-0.5
Full blood count includes
○ Hb concentration in g/l § Used to diagnose anaemia ○ Mean red cell volume ○ Mean red cell haemoglobin content § How much Hb in each red cell ○ Help to diagnose anaemia ○ Total WBC count § Neutrophil and lymphocyte count Important for diagnosing infection
What does a LFT’s blood test include?
○ Albumin concentration
○ Liver enzymes
Clotting factors
What does urea and electrolytes blood test for?
○ Test kidney function
○ And metabolic abnormalities
What is Blood glucose blood test for?
Test for diabetes mellitus
What is a lipid profile blood test for?
○ Triglycerides
○ Cholesterol
○ LDL and HDL
○ Important to identify cardiovascular disease