Circulatory System 1 Flashcards
Is blood a connective tissue?
Yes
What is blood composed of?
55% plasma and 45% of cells suspended within.
What does blood provide communication with?
Blood provides one of the means of communication between the cells of different parts of the body.
What is the function of blood?
It transports:
- Oxygen, carbon dioxide Oxygen, carbon dioxide
- Nutrients Nutrients
- Excretory products Excretory products
- Hormones (Endocrines) Hormones (Endocrines)
- Heat Heat
- Antibodies Antibodies
- Clotting factors
What is the composition of plasma?
90% water
10% dissolved substances
What are the dissolved substances that make up 10% of plasma?
- plasma proteins
- transported substances
What are the plasma proteins?
- albumin
- globulins
- fibrinogen
- prothrombin
- serum
What is albumin?
- formed in liver
- helps maintain viscosity of blood = ensures bloods not too thin and moving through vessels too quickly = maintaining blood pressure
What is globulins?
- formed in liver or lymphoid tissue
- produced during immune response
- transports hormones and minerals
What is fibrinogen?
- produced in liver - necessary for Haemostasis
What is prothrombin?
- essential substance in blood coagulation.
- vitamin k essential for its formation.
What is serum?
- its a plasma which clotting factors have been removed
What are the transported substances?
- enzymes
- hormones
- nutrients
- organic waste products
- dissolved gases
- dissolved inorganic salts
What are enzymes?
- chemical substances which can produce or speed up changes in other substances.
What are hormones?
- chemical substances from endocrine glands.
What are nutrients?
- amino acids
- glucose
- fatty acids
- glycerol
- vitamins
What are organic waste products?
- principally urea and uric acid
what are dissolved gases?
- carbon dioxide
- oxygen
- nitrogen
What are dissolved inorganic salts?
Mainly
- sodium
- potassium
- calcium
- chloride
- bicarbonate
(Responsible for maintaining blood pH-7.4)
What are the 3 blood cells?
- erythrocytes
- leucocytes
- thrombocytes
Where are erythrocytes formed?
They are formed in the red bone marrow
Why are erythrocytes corpuscles?
They are corpuscles because they have no nucleus.
Why are erythrocytes biconcave discs?
- biconcavity increases their surface area for gas exchange.
- the thinness of the central portion allows fast entry and exit of gases.
What is erythrocytes main function?
- gas transport, mainly of oxygen
How many erythrocytes are there per cubic millilitre of blood?
5 million per cubic millilitre of blood
Erythrocytes tend to clump together in groups - what is this called?
Rouleaux formation
What is erythrocytes life span?
120 days
What is development of erythrocytes known as?
Erythropoesis
What is necessary for erythrocyte maturation?
Vitamin B12
Where are erythrocytes ultimately destroyed?
In the spleen - haemolysis is carried out by phagocytic cells.
True or false erythrocytes contain haemoglobin?
True
- its an iron containing protein, involved with oxygen transportation around the body.
- iron released from haemolysis is retained and reused to form more haemoglobin.
What are erythrocyte disorders?
Anaemia
What are the types of anaemia from erythrocyte disorders?
- iron deficiency anaemia
- vitamin B12 deficiency anaemia
- sickle cell anaemia
Talk about thrombocytes
- not a true cell
- fragments of larger bone marrow cells
- important in blood clotting
Do thrombocytes have a nucleus?
No
How many thrombocytes are ther per cubic millilitre of blood?
- approx 250,000 per cubic millilitre of blood
What is the life span of thrombocytes?
8-10 days
What happens to thrombocytes not used in haemostasis?
They are destroyed in the spleen
What is the control of thrombocyte production?
- It is unclear
- thought to increase if there is a decrease in circulating thrombocyte count though
What are thrombocyte disorders?
Thrombocytopenia
- reduced platelet production
Congenital disorders
- haemophilia
- Von Willebrand’s disease
