A4 Vascular and Lymphatic System Flashcards
Describe the pulmonary circuit.
Oxygen-poor blood returns to the right atrium.
It is pumped to the lungs via pulmonary arteries.
Alveoli in the lungs perform gas exchange.
Oxygen-rich blood returns to the left atrium via pulmonary veins.
Arteries transport blood ____ the heart.
away from
Major characteristics of arteries.
thick walls
small lumen
low volume
tunica media (thickest layer)
Identify the two types of arteries in the human body.
muscular and elastic arteries
Describe elastic arteries
Largest arteries
Conducting
High elastin content
What is the function of elastin in arteries?
Allows for stretch and recoil to dampen pressure changes that result from the heart
Where are elastic arteries found in the human body?
aorta and major branches
Veins transport blood ____ the heart.
towards
Major characteristics of veins.
high volume
thin wall
thick lumen
tunica externa (thickest layer)
What is the main function of capillaries?
where gas and nutrient exchange occur between blood and tissues
How do capillaries normally exist?
in networks known as capillary beds
Major characteristics of capillaries
only tunica intima
very small lumen
identify the three types of capillaries.
Continuous
Fenestrated
Sinuosoidal
Where are continuous capillaries usually found?
muscle
lungs
skin
thymus
Where are fenestrated capillaries usually found?
small intestine
kidneys
endocrine glands
