Introduction to Blood Flashcards
For an average 70kg man, what is the volume of blood in the body and where is it distributed?
There are 5 litres of blood,
1 litre in the heart and arterial circulation
1 litre in the lungs
3 litres I’m the systemic venous circulation
State the functions of blood. (6)
Carriage of gas (e.g O2) Carriage of physiologically active compounds Clotting Defence Maintenance of ECF pH Thermoregulation
Blood is composed of (4)
Red blood cells (erythrocytes)
White blood cells (leukocytes)
Plasma
Platelets
Plasma is _ % of body weight and contains _% water
4
95
What does plasma do?
Circulates biologically active molecules compounds
Plasma proteins are subdivided into what 3 categories?
Albumin
Fibrinogen
Globulin
State what albumin does.
Transports lipid and steroid hormones
Helps create colloid oncotic pressure
State what globulin does.
Alpha and beta globulins transport lipids and fat - soluble vitamins
Gamma globulins are antibodies
What do fibrinogen have a role in?
Blood clotting
As a result of colloid oncotic pressure, what happens to the concentration and volume of fluid?
Concentration stays the same
Volume changes
State what happens to the value of colloid oncotic pressure going from the arterial end to the venous end.
Stays constant
State what happens to the value of capillary hydrostatic pressure going from the arterial end to the venous end.
Decreases
Colloid oncotic pressure acts ______
Capillary hydrostatic pressure acts _____
Into the capillary
Out of the capillary
State the lifespan of red blood cells.
120 days
Describe the structure and function of red blood cells.
Structure - Highly flexible, no nucleus and bi-concave
Function - To carry oxygen through the bloodstream using haemoglobin