Exam 2: Blood Vessels Flashcards
(32 cards)
What are the different types of blood vessels and what is their purpose?
Arteries: blood away from heart
Veins: blood towards heart
Capillaries: exchange vessels; thin walls
Describe the oxygen of arteries and veins
Arteries: systemic oxygen rich; pulmonary oxygen poor
Veins: systemic oxygen poor; pulmonary oxygen rich
What are the different layers of a blood vessel?
Tunica intima
Tunica media
Tunica externa
What is the cell type and role of each blood vessel layer?
Tunica intima: simple squamous epithelium; lines lumen of all vessels
Tunica media: muscular layer; maintain blood pressure
Tunica externa: connective tissue layer; collagen fibers
What are the different types of arteries?
Elastic, muscular, and arterioles
Describe the role of each type of artery
Elastic: largest artery; tunica media with elastic fibers
Muscular: thickest with most muscle; able to constrict and dilate
Arterioles: smallest artery; controls blood flow directly to capillary beds
Different types of capillaries and main function
Continuous: most common and found in skin, muscles, and lungs
Fenestrated: large pores to increase permeability; has a lot of holes
Sinusoid: least common and most permeable; in liver and bone marrow
How is blood flow controlled through capillary beds?
Controlled by diameter of terminal arteriole
Chemical conditions and and nerves can change flow
What different types of veins?
Venous sinuous: thin walls that hold large volume
Venous valves: prevent back flow
Varicose veins: very leaky which comes from pressure on lower limbs
How is blood flow maintained in veins?
te valves control blood and keep the blood flow in one direction
What does anastomoses mean?
Provides different pathways for blood to enter body
What controls blood flow and resistance to blood flow in vessels?
the constriction of arterioles
Describe each measure of blood pressure
Systolic: peak with ventricular contraction; first sound you hear
Diastolic: end of low pressure; maintained by elastic walls
How do you measure blood pressure in the clinical setting?
You use an inflatable cuff and and wrap it around the brachial artery
How is blood pressure maintained in veins?
It increases when skeletal muscles contract
Describe musclular pump
Skeletal muscle “milks” blood towards heart
Valves keep it from flowing back
Describe respiratory pump
Abdominal pressure from breathing forces blood to the heart
Describe sympathetic vasoconstriction
When smooth muscle around veins constrict
How do hormones control blood pressure?
The adrenal gland releases hormones that regulate blood pressure
What is the renin-angiotensin-aldosterone system?
system of hormones and enzymes that regulates you blood pressure and volume on a long term basis
What is considered low and high blood pressure?
Low: hypotension 90/60
High: hypertension 140+/90+
What is and causes circulatory shock?
When blood vessels aren’t filled correctly
What is hypovlemic?
Causes by large blood and fluid loss
What is vascular shock?
Normal volume but extreme vasodilation (enhances blood to areas lacking oxygen)
