Blood Vessels Flashcards
(46 cards)
What are the five main blood vessels?
Arteries Arterioles Capillaries Venules Veins
What builds up the structure of blood vessels? (3)
Tunica Externa
Tunica Media
Tunica Interna
What is the Tunica Externa?
The outer fibrous sheath formed of elastin and collagen
What is the Tunica Media?
The middle layer of smooth muscle and elastic tissue
What is the Tunica Interna?
The smooth lining of squamous epithelium in the centre of blood vessels.
What is the role of arteries?
They take oxygenated blood away from the heart and delivers it to the capillaries.
What is the exception for the role of arteries?
The pulmonary artery which carries blood deoxygenated blood away from the heart to the lungs to be oxygenated.
What are the different types of artery in the body?
Carotic artery Radical artery Femural artery Aorta Brachial artery Pulmonary artery
What is the role of precapillary sphincters?
It is a band of smooth muscle that adjusts and controls blood flow into capillaries
What is the role of capillaries? (3)
Links the arterial and venous systems
Allow the interchange of gases and the transfer of nutrients to and waste products
Single layer of cells (short diffusion pathway)
What is the 3 different kinds of capillaries?
Continuous
Fenestrated
Sinusoid
What kinds of substances are exchanged through a semi-permeable membrane?
Glucose Fatty acids Amino acids (protein) Gases Vitamins Minerals
What is tissue fluid?
It is the fluid that fills the space between the cells
It is formed when plasma in the blood is forced through the gaps in the capillary walls except for those components that are too large
What is osmotic pressure?
It’s pressure that pulls fluid back in via the venous system
What is hydrostatic pressure?
The pressure blood is under as it enters the capillaries due to the search of blood as the heart contracts.
What is oncotic pressure?
The tendency of water to move into the blood by osmosis.
What is the two ends of the capillary called?
Arterial end and venous end
What is the role of the venous system?
The deoxygenated blood from the capillaries and delivers it to the heart
What is the exception for the venous system? (Veins)
The pulmonary vein as it carries oxygenated blood from the lungs to the heart
What are the different veins in the body?
Vena cava Pulmonary vein Jugular vein Hepatic vein Renal vein Popliteal vein
Factors that affect the diameter of blood vessels?
Vasodilation Vasoconstriction Medicines Drugs Alcohol Temperature
What is the autonomic nervous system?
It controls the smooth muscles in the arteries and veins
It controls involuntary functions in the body including heart beat
Where does the nerves from the autonomic nervous system come from?
The vasocentre in the medulla oblongata
What does the autonomic nervous system divide into?
The sympathetic and parasympathetic nervous system