Flashcards in Introduction to Vasculature Deck (36)
What are the three major components of the cardiovascular system?
The heart, blood vessels and blood
What is the major function of the cardiovascular system?
Transportation of: nutrients and oxygen, waste products, and hormones
Approximately how many miles of blood vessels are there in the cardiovascular system and how many of those miles are capillaries?
60,000 miles total 50,000 miles are capillaries
What are the four chambers in the heart?
Right atria and ventricle and left atria and ventricle
What does the left side of the heart do in terms of the atrium and ventricle?
The left atrium receives oxygenated blood, and the left ventricle pumps blood to the systemic circuit
What does the right side of the heart do in terms of the atrium and ventricle?
The atrium receives deoxygenated blood and the ventricle pumps blood for the pulmonary circuit
What are the three major types of blood vessels?
Arteries, capillaries, and veins
What is the best definition for an artery?
An artery carries blood away from the heart
What is the best definition for a vein?
A vein carries blood towards the heart
What is a capillary?
The smallest of blood vessels; thin wall, their main role is to allow the exchange of materials between the blood and body tissues
The walls of blood vessels have how many layers or tunics and what are they?
Three; 1) tunica interna or tunica intima; 2) tunica media; 3) tunica externa or tunica adventitia
What are the three parts of the tunica interna or the tunica intima?
a. endothelium (simple squamous); b. basal lamina; c. subendothelial layer
What is the layer in between the tunica interna and the tunica media of arteries and some arterioles?
The internal elastic membrane
Define the tunica media.
This layer is the middle layer and contains rings of smooth muscle cells responsible for vasoconstriction and vasodilation; can also contain sheets or lamellae or laminae of elastin
Define the tunica externa.
This is in larger vessels and contains a vasa vasorum and a nervi vascularis
In a cross section would a vein or artery be more collapsed or more open?
An artery would be more open and a vein would be more collapsed
What is the thickest layer of an artery?
The tunica media
What is the thickest layer of a vein?
The tunica externa
Is a vein as thick as its corresponding artery?
No a vein will be thinner
Is the lumen of an artery as large as its corresponding vein?
No the lumen of an artery will be smaller than its corresponding vein
Describe elastic or conducting arteries.
(Large arteries) these are the largest in diameter arteries that are greater than 10 mm; walls contain large amounts of elastic fibers; allows arteries to expand and recoil; important vessels in helping to propel blood onward while ventricles are relaxing; elastic fibers function as pressure reserve
Describe muscular or distributing arteries.
(Medium arteries) These arteries are medium sized arteries that are 2 mm to 10 mm; walls contain large amounts of smooth muscle; important in regulating the blood flow to specific body regions; smooth muscle cells in circular orientation and are responsible for vasoconstriction and vasodilation
Describe small arteries.
0.1 mm to 2 mm in diameter; as many as eight layers of smooth muscle in their tunica media
Smallest diameter artery; 10 micometers - 100 micrometers in diameter; only one or two layers of smooth muscle in the tunica media
What is the diameter of a capillary?
4 micrometers to 10 micrometers
How many walls do capillaries have?
Two, endothelial membrane (nonkeritanized simple squamous epithelium) and its basal lamina
What is the main role of capillaries?
To allow exchange of materials between the blood and body tissues
What are the four types of veins?
Venules, small veins, medium veins, and large veins
What are the two kinds of venules?
Postcapillary venule and muscular venule