Introduction to the structure and function of blood Flashcards
What is the structure of blood
Structure of blood:
-Plasma(fluid)
-Cells
-Red cells
-White cells
-Platelets
What is the top, middle and bottom layer of blood after centrifuging?
-Top layer is plasma
-In between the top and bottom layer, there is a buffy coat which consists of white cells
-Bottom later is red cells
What are red blood cells also referred to as?
-Also referred to as erythrocytes
What shaped discs are red blood cells
Biconcave discs
Is there genetic information in red blood cells
-Has no nucleus, no DNA, RNA or mitochondria
Average lifespan of Red blood cell
-Average life span is around 120 days
Diameter of RBC
Diameter is 8μm
Thickness of RBC
Thickness is 2μm
What are white blood cells also referred to as?
Also referred to as leukocytes
Colour of WBC?
They’re colourless
What are the 2 most common types of white blood cells
-The two most common types are:
-Neutrophils
-Lymphocytes
What does it mean by neutrophils being polymorphnuclear?
-Meaning they are irregular and multi-lobed nucleus
Are neutrophils granulocytes and what are granulocytes?
yes and this means they contain prominent cytoplasmic granules
What are examples of other granulocytes?
Eosinophils and Basophil
What stain is used for the granules in eosinophils and what colour do they stain?
-The granules stain red with eosin(1-4% of WBC)
What stain is used for the granules in Basophil and what colour do they stain?
-The granules stain blue/purple with basic dyes(<0.5% of wbc)
Do Mononuclear cells have granules?
Lack granules
Describe nuclei of mononuclear cells?
Large, regular nuclei
What are the 2 types of mononuclear cells
-2 types:
-Monocytes
-Lymphocytes
What are platelets
Cytoplasmic fragments
Do platelets have a nucleus?
No nucleus
What are platelets bound by?
Membrane bound
Do platelets contain granules?
Contains granules
Where do blood cells come from?
Mature blood cells are produced from stem cells in the bone marrow
What is plasma and what does it contain?
-Fluid containing:
-Water
-Salts
-Proteins
-Organic molecules
-Metabolites
-Carbohydrates
-Lipids
What is serum?
Serum is the fluid left after blood clotting
What percentage of protein is normal in plasma?
Normal: 7-9% of plasma is protein
What protein is >90% of the protein plasma?
But >90% is a single protein: albumin
What is the function of blood
-Transport
-Defence
-Homeostasis
What does blood carry and remove?
-Carry oxygen/nutrients to tissue
-Remove CO2/ other waste products from tissues
Transport of oxygen and CO2 and what enzymes aid it
-For example erythrocytes aka RBC transport oxygen from the lungs to the body tissues as well as carrying CO2 in the form of bicarbonate
-The red cell enzyme carbonic anhydrase helps CO2 to:
-Dissolve in plasma in the tissues
-Come out of solution in the lungs
What carries the poorly soluble substances and what are these substances?
-Plasma proteins carry substances which are poorly soluble in water
-lipids
-lipid soluble hormones and vitamins
What carries metal ions in the blood and what are examples?
-Plasma proteins also carry metal ions like
-Ca2+
-Fe2+
-Cu2+
What is haemoglobin and its structure?
-Protein tetramer made up of 4 polypeptide chains:
-2 alpha globin chains
-2 beta globin chains
What does each globin chain carry in haemoglobin?
-Each globin chain carries a haem molecule
What atom does haem hold?
-The haem holds a ferrous(Fe^2+) iron atom
How does oxygen bind to haemoglobin?
Oxygen binds reversibly to the iron atom by a coordination bond
What does a pulse oximetry measure and determine?
-Measures the colour of the haemoglobin
-Determines if the patient is hypoxic
What do neutrophils do and what are they main mediators of?
-Phagocytose and kill bacteria and fungi
-Main mediators of innate immunity
What do lymphocytes mediate, what do they produce and what do they do?
-Main mediators of adaptive immunity
-Produces antibodies
-Kill virus infected cells
What do eosinophils kill and what are they involved in?
-Kill parasites
-Involved in allergic response
What are basophils and what are they involved in?
-Kill parasites
-Involved in allergic response
-Involved in inflammation
What do monocytes(macrophages) do?
Phagocytosis of dead cells and pathogens
What are immunoglobulins made by and what do they act as?
-Made by B-lymphocytes
-Act as antibodies against pathogens
What does complement proteins kill and what cells do they cooperate with?
-Kill bacteria and other pathogens
-Cooperate with Ig and WBC
What is the major role of platelets and how do they do that?
-Major role: Primary haemostasis
-Recognise damage at blood vessel wall
-Form a platelet plug
-Prevent/stop bleeding
-Platelet plug stop bleeding-but insecure and temporary
What are the basic steps in haemostasis within the plasma?
-Fibrinogen is a major plasma protein
-Converted to Fibrin, forms blood clot
-Clotting factors control process
-Fibrin clot reinforces primary platelet plug
What is total blood volume for a 70kg male and what is that in ml per kg?
Total blood volume is around 5 litres for a 70kg male
-Therefore it is about 70ml per kilogram
What is haematocrit also known as?
-Also known as packed cell volume
= volume of vells/total volume
What does having too little or too many red cell in a given volume in haematocrit indicate?
-Having too many or too little red cells in a given volume may indicate disease
What does a full blood test include?
-Haemoglobin concentration (Hb in g/l) / Mean (red) cell haemoglobin content(MCHC)
-Mean red cell volume(MCV)
-Haematocrit (RBC vol/total vol)
-White blood cell count
-Platelet count
What is Haemoglobin concentration and what is it used to diagnose?
-overall concentration of haemoglobin in the blood
-Used to diagnose anaemia
What is mean red cell haemoglobin content?
-How much Hb in each red cell
What is the mean corpuscular volume?
-Size of the RBCs
What does the white blood cell count in a full blood count test include and why are these important?
-Total white blood cell count
-Neutrophil count
-Lymphocyte count
Important to diagnose infection
What do liver function tests check for?
-Check albumin concentration
-Liver enzymes(released from damaged liver cells)
-Clotting factors
What do urea and electrolytes test do?(U&E)
-Test kidney function
-And metabolic abnormalities
What do blood glucose tests do?
-Test for diabetes
What does a lipid profile consist of?
-Triglycerides
-Cholesterol
-LDL and HD
