Chapter 19 Flashcards
What are the three layers of blood vessels
tunica intima, tunica media, and tunica externa
What makes up the tunica intima
simple squamous
What. makes up the tunica media
smooth muscle
What makes up the tunica externa
connective tissue
What is the vasa vasorum
microvasculature that plays a role in vessel wall biology and pathology
Where are elastic arteries located
nearest to the heart
What are elastic arteries made of
much more elastic tissue in the tunica media
What are conducting arteries
an artery with many collagen elastin filaments in tunica media allowing it to stretch with each pulse
What arteries make up the most of the named arteries
distributing arteries
How are distributing arteries unique
contain more smooth muscle cells in tunica media layer than elastic arteries
What are resistance arteries
small diameter blood vessel in microcirculation that contributes to the creating of resistance to flow
What layers are in capillaries structure
endothelial cells, epithelial cells
What do pericytes do
maintain blood brain barrier, blood vessel formation, regulate immune cell entry to CNS
What tissues have no capillaries
epidermis, lens and cornea
Where are continuous capillaries located
kidneys small intestine endocrine glands
Fenestrated capillaries do what
active filtration, absorption, hormone secretion
Why do sinusoidal capillaries have sluggish blood flow
allows time for modification of large molecules and blood cells that pass between blood and tissue
Why are there macrophages in the sinusoidal capillaries
innate and adaptive immunity
What is the precapillary sphincter
controls blood flow to capillary beds
What are venules
very small veins
What are varicose veins
twisted enlarged veins
What are venous sinuses
group of sinuses that drain venous blood flow from cranial cavity
What are vascular anastomoses
surgical procedure that is used to connect vessels to each other
What is blood flow
flow of blood in circulatory system
What is systemic arterial blood pressure
force when left ventricle contracts
What are the three factors in blood resistance
blood viscosity, vessel length, and vessel diameter
What is laminar flow
smooth and streamlined
What is turbulent flow
are irregular and chaotic
Atherosclerosis
hardening of arteries
What are factors of arterial blood pressure
age gender body weight activity level stress alcohol intake
What is Systolic pressure
pressure in arteries when your heart beats
What is diastolic pressure
pressure in arteries when heart rests between beats
What is pulse pressure
the top number minus the bottom
What are the vital signs
body temp, pulse rate, respiration rate, blood pressure
What are the sounds in blood pressure called
korotkoff
Why is capillary blood pressure so low
ensure blood and oxygen can diffuse into tissues
What is the Muscular pump
collection of skeletal muscles that help veins return blood flow
What is the Respiration pump
pressure changes during breathing help veins bring blood back
What causes sympathetic venoconstriction
increase in venous return
What is MAP maintained by
renal system
What happens to the baroreceptor reflexes when MAP is high
dilate vessels
What is vasodilation
widening of blood vessels as a result of relaxation of the blood vessels muscular walls
What is arteriolar vasodilation
dilation of arteries
What is venodilation
dilation of veins
what is decreased cardiac output
inhibit sympathetic activity and stimulate parasympathetic
What is the role of vagus nerve in heart rate
decrease heart rate
what happens if MAP is low
reflex vasoconstriction is initiated that increases CO and BP
the Aortic arch and large arteries of the neck can detect changes in what
blood pressure
Where are reflexes that regulate blood pressure found
adrenal medulla controlled by hypothalamus
What do adrenal medulla hormones do to BP
increase vasoconstriction increasing BP
What is the effect of Angiotensin 2 on blood pressure
causes the muscular walls of small arteries to constrict and increase BP
What does ADH do to blood pressure
increases
What does atrial natriuretic peptide do the blood pressure
decreases BP
What is direct renal regulation
when BP high kidneys excrete more when BP low kidneys excrete less
What is indirect renal regulation
renin-angiotensin-aldosterone mechanism
Aldosterone cause what
increase in BP
What are ACE inhibitors and who takes them
medications that relaxes veins and arteries used by people with high BP
What are the risks for primary hypertension
diabetes unhealthy diet obesity and alcohol consumption
What is secondary hypertension caused by
coarctation of the aorta, sleep apnea, obesity, pregnancy and medications
What is orthostatic hypotension
low BP when standing after sitting or lying down
What is chronic hypotensions
life-long hypotension
What is acute hypotension
a sudden drop in blood pressure
What causes hypovolemic shock
severe blood or other fluid loss
What causes vascular shock
when blood vessels dilate to much
What causes cardiogenic shock
usually a heart attack
How is blood flow to each organ controlled
perfusion pressure and vasomotor tone
what is Vasomotion
spontaneous oscillation in tone of blood vessel walls independent of heartbeat
What is edema
swelling caused by too much fluid trapped in body tissues
What are the reflex factors in blood pressure
medulla cardiovascular centers, barorecptors, chemoreceptors, higher brain centers
Where are baroreceptors and why are they there?
aorta and carotid sinus because it is close to the brain and coming right off of the heart
What does hydrostatic pressure have to do with capillary beds
pushes fluid out on arterial end
What does osmotic pressure have to do with capillary beds
brings fluid back in on venous end
what is Colloid osmotic pressure
presence of non-diffusible molecules in fluid such as proteins
what is Capillary colloid osmotic pressure
osmotic pressure from large molecules to bring fluid back into capillary on venous end
what is net filtration pressure
total pressure that promotes filtration
What is the hydrostatic pressure in capillaries
35 mmHg
what happens to the osmotic pressure as it moves along the capillary
it decreases making water move back in
What is interstitial fluid hydrostatic pressure
interstitial pressure that increases as fluid leaves capillaries and enters tissues
What are lymphatics
tubes that drain fluid into lymph nodes
What is the importance of lymphatics
manage body fluid levels in balance and defend against infection
What causes an increase in hydrostatic pressure in capillaries
more fluid loss from blood/ increase in BP
What can cause and increase in interstitial fluid osmotic pressure
an inflammatory response
What can cause a decrease in capillary colloid osmotic pressure
improper plasma proteins causes fluid to pool in tissues
