Circulatory Systems I Flashcards
How much blood is composed of plasma?
55%
What are the functions of blood?
Transports: - oxygen & CO2
-nutrients
-excretory products
-hormones
-heat
-antibodies
-clotting factors
Describe the structure of plasma?
- 90% water
- 10% dissolved substances ( plasma proteins and transported substances)
What are the different plasma proteins?
- albumin
- globulins
- fibrinogen
- prothrombin
Where is albumin formed?
In the liver
What is the function of albumin?
Albumin helps maintain viscosity of the blood, ensuring blood is not to thin and moving through BV too fast - therefore maintains BP
Where are globulins formed?
Liver or lymphoid tissue
What is the function of globulins?
- produced during immune response
- transports hormones and minerals
Where is fibrinogen produced and what is its function?
The liver and fibrinogen is necessary for haemostasis
What is the function of prothrombin?
Essential substance in blood coagulation
What is essential for prothrombin formation?
Vitamin K
what is serum?
plasma which clotting factors have been removed
what are some transported substances?
- enzymes
- hormones
- nutrients (amino acids, glucose, fatty acids, vitamins)
- organic waste products (urea and uric acid)
- dissolved gases &inorganic salts
what is another term for a red blood cell?
Erythrocyte
where are erythrocytes formed?
red bone marrow
do erythrocytes have a nucleus?
No- they are corpuscles
describe the reason for erythrocytes biconcave shape?
their biconcavity increases their surface area for gas exchange, and the thinness of the central portion allows fast entry and exit of gases
what is the main function of an erythrocyte?
gas transport, mainly of oxygen
describe the characteristics of an erythrocyte?
- tend to clump together in groups ‘rouleaux formation’
- 5mil per cubic mm of blood
- life span is 120 days
what is the development of erythrocytes known as?
erythropoiesis
what is necessary for erythrocyte maturation?
vitamin B12
name an erythrocyte disorder?
anemia: - iron deficiency anemia
- vitamin B12 deficiency anemia
- sickle cell anemia
what is another name for a platelet?
Thrombocyte
describe the characteristics of a thrombocyte
- approx. 250,000 per cubic mm of blood
- life span of 8-10 days
- those not used in hemostasis are destroyed in spleen
what is a thrombocyte?
- not a true cell
- corpuscle
- fragment of larger bone marrow cells
how is thrombocyte production controlled?
it is unclear, but its thought to increase if there is a decrease in circulating thrombocyte count
what are some thrombocyte disorders?
- thrombocytopenia (reduced platelet production)
- congenital disorders eg. hemophilia and von Willebrand’s disease
