CVS System Flashcards
What are the 6 aspects of the CVS system
Blood
Heart
Arteries
Veins
Capillaries
Lymphatics
Where is the low pressure of the circulatory system
In the lungs pulmonary
What is the higher pressure in the circulatory system
Systemic
What are the 3 layers of the heart wall
Endocardium
Myocardium
Epicardium
What is the endocardium layer
Endothelial inner layer
What is the myocardium layer
Cardiac muscle is the bulk of the heart
What is the epicardium layer
Visceral pericardium
From the outside in list the 4 layers of the heart wall
Parietal pericardium
Visceral pericardium
Myocardium
Endocardium
Where is the pericardial cavity
Between the parietal pericardium and the visceral pericardium
Why is the left ventricle the thickest
In order to supply systemic circulation as the thickness of the myocardium varies according to function
What are the 3 functions of the pericardium
Protects and anchors the heart
Prevents overfilling
Provides a friction free environment
Which major vessels bring blood to the heart
Superior and inferior vena cava
Right and left pulmonary veins
Which major vessels takes blood away from the heart
Pulmonary trunk then right and left pulmonary arteries
Ascending aorta
What are the 3 main layers of blood vessels (in order from inside to out)
Intima (tunica)
Media
Adventitia
List 5 adaptations of the arteries
Thick wall
Elastic
Muscular
Large diameter
Low resistance
List an adaptation of the arterioles
Smaller diameter
What is the function of arterioles
Major role in blood pressure regulation
What are capillaries made from
Single tube of endothelial cells
What is the role of pericytes
Important in blood vessel formation and maturation may have immune roles
What are the 3 types of capillaries
Continuous
Fenestrated
Sinusoidal (discontinuous)
Which is the most common capillary type
Continuous
What are fenestrated capillaries
Leaky pores
Found in the kidney, intestine, pancreas, endocrine glands
Easier exchange
What are sinusoidal capillaries
Liver, spleen, bone marrow, lymph nodes, larger openings for blood cells, microorganism
What are the ‘cuffs’ of smooth muscles called
Sphincters
What do the sphincters do
They are at the end of smooth muscles that contract or relax helping to direct blood to where it is needed or away from where it is not needed
Where does the control of blood flow originate from
Where capillaries originated from arterioles
What do venules and veins do
Return blood to the heart
What is the pressure in venules and veins
<15 mm Hg
What do venules and veins consist of
Large lumen
Some smooth muscle
What are venules
The smallest veins which receive blood from capillaries
What are 5 adaptations of veins
Capacitance vessels (60% of blood)
Unidirectional valves
Deep
Superficial
Connecting/perforating
How much of the circulating blood volume is below the heart
70%
How do skeletal muscles help the CVS
Through movement which compresses intramuscular veins to prevent pooling
During inspiration what has the higher pressure and what has the lower pressure
A lower thoracic pressure
A higher abdominal pressure
What does the lymphatic system do
Return interstitial fluid to circulation at subclavian veins
To prevent oedema and maintain blood volume/pressure
How does the lymphatic system move
By muscular contraction
