Chapter 18 - Circulatory system Flashcards
Transports blood away from the heart
Arteries
Transports blood to the heart
Veins
Exchanges substances between blood and tissues ; interconnects smallest arteries and smallest veins
Capillaries
Conducts blood between the heart and peripheral tissues
Blood vessels
To and from gas exchange surfaces in the lungs
Pulmonary circuit
To and from rest of body
Systemic circuit
Each circuit begins and ends with the _____ and occurs in _____.
Heart ; sequence
What is the entry chamber?
Right atrium
What is the pathway for the right atrium? and what does it do/what kind of blood?
To right ventricle to pulmonary circuit ; collects blood from systemic circuit ; oxygen-poor blood
What is the pathway for the pulmonary circuit? What kind of blood?
Pulmonary arteries to pulmonary capillaries to pulmonary veins ; oxygen-poor blood
What is the pathway for the left atrium? What kind of blood?
Receives blood from pulmonary circuit ; to left ventricle to systemic circuit ; oxygen-rich blood
What is the pathway for the systemic circuit? What kind of blood?
Systemic arteries to systemic capillaries to systemic veins ; oxygen-rich blood
What are the 5 general blood vessel classes?
Arteries, arterioles, capillaries, venules, and veins
Large vessels close to the heart that stretch and recoil when heart beats ; include pulmonary trunk, aorta, and branches
Elastic arteries
Medium-sized arteries ; distribute blood to skeletal muscles and internal organs
Muscular arieries
Poorly defined tunica externa ; tunica media is only 1-2 smooth muscle cells thick
Arterioles
Only blood vessels to allow exchange between blood and interstitial fluid ; very thin walls allow easy diffusion
Capillaries
What do the venules include and what do they do?
Small veins (those smaller than 50 m lack a tunica media and resemble expanded capillaries) ; collect blood from capillaries
What do the veins include?
Medium-sized veins
What are medium-sized veins?
Smaller than arteries ; range from 2-9 mm in internal diameter ; thin tunica media with smooth muscle cells and collagen fibers ; thickest layer is tunica externa with longitudinal collagen and elastic fibers
