Haematology Lecture 1 Flashcards
What is haematology
The study of the normal and pathological aspects of blood and blood elements.
List disorders that affect blood
➢ Bleeding disorders
➢Haematological malignancies ➢Haemoglobinopathies
➢ Blood transfusion
➢Bone marrow and stem cell transplantation
Where are all blood cells produced
Bone marrow
What type of tissue is blood
Connective
Physical characteristics of blood
➢Sticky, opaque fluid with metallic taste
➢Colour varies with O2 content High O2 - scarlet; low O2 - dark red
➢pH 7.35–7.45
What type of blood is dark red and why
Venous as it has less oxygen
What type of blood is bright red
Arterial
Role of blood
-transport
-regulation
-protection
Role of blood:transport
-Delivering O2 and nutrients to body cells
-Transporting metabolic wastes to lungs and kidneys for elimination
-Transporting hormones from endocrine organs to target organs
Function of the blood:regulation
-Maintaining body temperature by absorbing and distributing heat eg vasoconstriction or dilution
-Maintaining normal pH using buffers; alkaline reserve of bicarbonate ions
-Maintaining adequate fluid volume in circulatory system
Functions of the blood:protection
-Prevents excess blood loss following injury
Due to Platelets and Plasma proteins
-prevents infection due to white blood cells(leukocytes), antibodies,complement proteins
Blood composition
-erythrocytes
<45% of whole blood(haematocrit)
<most dense component due to globular proteins
-buffy coat
<1%of whole blood contains the leukocytes and platelets
-plasma
<55% of whole blood
<least dense component
What is plasma composed of
-Water
-Ions
-Organic molecules such as amino acids,proteins,glucose,lipids or nitrogenous waste
-trace elements and vitamins
-gases such as co2 and o2
What are albumins
-Protein made in the liver
-It also helps move hormones, medicines, vitamins, and other important substances throughout the body.
What are globulins
which help fight infection and move nutrients throughout the body. Some globulins are made by the liver.
What are fibrinogen
Function is coagulation
What are cellular element composed of
-Red blood cells
-white blood cells which include lymphocytes,monocytes,neutrophils,eosinophils,
basophils
-platelets
What is haematocrit
Represents the % of erythrocytes in whole blood
42% in female and 47 in men
What are leukocytes
-sense infections
-make up to <1% of total blood volume
-the function is defuse against disease
-can leave capillaries via diapedesis
-move through tissue spacers by ameboid motion and positive chemotaxis
Types of phagocytes
Neutrophil
Monocyte
Basophil
Eosinophil
What is in the granules of basophils
Histamine
Role of b cells
Secretion of antibodies
Role of natural killer cells
Lysis of virally infected cells and tumour cells
Role of t helper cells
Release cytokines and growth factors that regulate other immune cells
Role of cytotoxic T cells
Lysis of virally infected cells tumour cells as well as allografts
Role of b cells
Secretion of antibodies
Abundance of leukocytes in the blood
Never let monkeys eat bananas
Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils
Erythrocytes
-most abundant cell in body
-red blood cells dedicated to respiratory gas transport (specialised to transport oxygen and carbon dioxide|)
-major factor contributing to blood viscosity
-life span 120 days
-filled with haemoglobin for gas transport
Structural characteristics of erythrocytes
-biconcave disc
-anucleate
-no mitochondria or ribosomes
-no organelles
How do erythrocytes produce energy
-no mitochondria so can’t produce atp
-do it through the em den Meyerhof glycolytic pathway(anaerobic respiration)
Glycolysis
Make notes
Red cell membrane
-lipid bilayer
-alpha and beta spectrum which provided flexibility to change shape(its below plasma membrane)
Haemoglobin structure
-binds reversibly with oxygen
-glob is a large protein composed of 4 polypeptide chains(tetramer)
-2 alpha and 2 beta chains
-each red blood cells contain 200-300 million he molecules
-normal values:m 130-180g/l , f 120-160g/l
-each contains a haem-iron complex
Featal haemoglobin
Has 2 alpha and 2 gamma chains as it has a higher affinity for oxygen
What is haemoglobin made of
Organic part of protoporphyrin ring made up of four pyrrole rings and central iron ion In the ferrous state
How many molecules of oxygen can heamoglobin transport
4 o2 molecules
O2 loading in lungs
-produces oxyhemoglobin (ruby red)
-in the lungs 02 abundant
-by picks up 4 molecules of o2 and becomes saturated
O2 unloading in tissues
-the tissues have a lower amount of 02 and therefore it released from HB
-produces deoxyhaemoglobin or reduced haemoglobin (dark red)
-the tissues/muscles produce co2 which reduces affinity for oxygen as it makes it more acidic which causes 02 to be released
Co operative oxygen loading
-first oxygen that binds changes the tertiary structure which makes it easier for other oxygen molecules to bind
What is a tetramer
Polymer consisting of 4 monomers
What is a ferrous state of iron
Fe2+
What is diapedesis
How white blood cells move out of the circulatory system and towards the side of tissue damage or infection
Ameboid motion
Crawling like cell migration
Positive chemotaxis
Movement of cellos towards a higher contraction of a stimulating substance(attractant)
