Anatomy: blood and lymph circulation Flashcards
What is sympathetic tone of arteriolar smooth muscle?
a background, low level of contraction
due to tonic (continuous) conduction of action potentials to arterioles by sympathetic nerves
What are the four parts of the aorta?
The ascending aorta
The arch of the aorta
The thoracic aorta
The abdominal aorta
How many branches does the ascending aorta have?
2- the left and right coronary arteries
How many branches does the arch of the aorta have?
3
How many branches does the thoracic aorta have?
Numerous
how many branches does the abdominal have?
3 unpaired midline branches
3 paired , bilateral branches
What are the three branches of the arch of the aorta?
The brachiocephalic trunk
The left common carotid artery
The left subclavian artery
What does the brachiocephalic trunk bifurcate into?
The right common carotid artery
The right subclavian artery
What does the right common carotid artery bifurcate into?
The right internal carotid artery
The right external carotid artery
What happens to the right external carotid artery?
What does it supply?
remains external to cranial cavity to supply face & scalp
What happens to the right internal carotid artery?
What does it supply?
becomes internal to cranial cavity via the carotid canal to supply the brain
Name an artery that branches off of the right subclavian artery and ascends in the neck .
Where does it go?
The right vertebral artery
Passes through transverse foraminae in cervical vertebrae then through foramen magnum to enter the cranial cavity
Where is the circle of Willis?
What is it?
On the inferior aspect of the brain
It is an anastamosis
What is formed when the left and right vertebral arteries join together?
The basilar artery
It is found on the inferior aspect of the brain
What is the carotid sinus?
Where is it located?
The most proximal (usually dilated) part of the internal carotid artery
It is located at the level of the superior border of the thyroid cartilage
What innervates the carotid sinus?
the glossopharyngeal nerve (CN IX)
What is the function of the carotid sinus?
to detect stretching of the walls of the carotid sinus (i.e. beat to beat changes in arterial blood pressure)
What does the carotid body do?
What innerverates it?
It is also supplied by CN IX
It monitors blood gas levels/pH