Lecture Exam #1 Ch. 21 Flashcards
detects CO2 in blood, uses chemical sensitive neuron.
chemoreceptor reflex
inflammation of the veins
phlebitis
when blood flow to part of your brain is stopped either by blockage or the rupture of a blood vessel
Cerebrovascular accidents (CVAs) (Stroke)
does artery or vein blood move faster and why?
artery because there is much higher pressure
which arteries do we change the size of?
muscular arteries and arterioles
what kind of cell is the tunica adventitia?
connective tissue
the pressure at which the sound disapears
diastolic pressure
what does the hepatic portal vein carry?
blood to series of capillaries (sinusoids) in the liver
a cross sectional area of blood vessel goes up what happens?
velocity of blood goes down
what are some characteristics about elastic arteries? (3) (BUL)
1) biggest
2) up to 2.5 cm
3) lots of elastin
results when the veins of the lower limbs are steched to the point that the valves become incompetent.
varicose veins
what are capillaries made of?
simple squamous epithelium
what happens to blood pressure with vasodialation?
it goes down
what are the parts of the internal elastic membrane of both veins and arteries? (3) (TTT)
1) tunica media
2) tunica adventitia
3) tunica intima
as the diameter of vessels decrease what is ocuring?
the total cross-sectional area increases and velocity of blood flow decreases
what parts of the human body can a pulse be taken? (10( SCFABRFPDP)
1) superficial temporal artery
2) common carotid artery
3) facial artery
4) axillary artery
5) brachial artery
6) radial artery
7) femoral artery
8) popliteal artery
9) dorsalis artery
10) posterior tibial artery
what is greater at the arterial end of the capillary?
net hydrostatic pressure is greater than net osmotic pressure
what are some characteristics of veins? (3) (TLL)
1) thinner
2) larger diameter opening
3) looks deflated
what happens to blood flow when the precapillary sphincters constrict?
it decreases
detects changes in blood pressure and produces changes in heart rate, heart force of contraction and blood vessel diameter that return blood pressure to homeostatic levels
baroreceptor reflex
which layer of the internal elastic membrane touches the blood?
tunica intima
the measure of the force the blood exerts against blood vessel walls
bloop pressure
what is true of all capillaries?
they all leak
when do we use the chemoreceptor reflex?
in times of emergency
in a chemoreceptor reflex what does a decrease in carbon dioxide and an increase in blood pH result in?
a decreased HR and vasodilation
about how much of the fluid passes into lymphatic capillaries?
one-tenth
at the venous end which is less?
the net hydrostatic pressure is less than the net osmotic pressure
what are some examples of elastic arteries? (6)(APCCBS)
1) aorta
2) pulmonary
3) common carotid
4) common iliac
5) brachiocephalic
6) subclavian
resistance to blood flow through vessels and especially arterioles
vascular resistance
The sounds we hear of blood flow turbulance and the vibrations in blood and surrounding tissues
Korotkoff sounds
what canthe antidiuretic hormone (Vasopressin) mechanism increase?
the osmolality of blood
what system control heart rate and vessel size
nervous system
what does gangrene result from?
if the inflammation is severe and blood flow becomes stagnant in a large area
what are some characteristics of arteries? (3) (RTN)
1) rounder
2) thicker wall
3) narrower opening
if blood flows out what does that mean?
severed vein
if you have too much carbon dioxide what happens to your blood pressure?
it goes up
what can severe shock damage?
vital body tissues to the extent that the patient dies
what does a positive net filtration pressure cause?
fluid to move out of the capillary
what does a negative net filtration pressure cause?
fluid to move into the capillary
what happens to blood pressure with vasoconstriction?
it goes up
which are the most common changes from blood pressure?
heart rate and vessel size
when he net osmotic pressure is subtracted from the net hydrostatic pressure at the arterial end what do you get as a result?
a positive net filtration pressure
what are mechanisms that change blood volume?
baroreceptor and chemoreceptor
instrument for measuring blood pressure
sphygmomanometer
what is a consequence of varicose veins?
the venous pressure is greater than normal in the veins of the lower limbs, resulting in edema
a bulge that forms in it sometimes when a part of arterial wall becomes weakened
aneurysm
inadequate blood flow throughout the body due to failure of the mechanisms to maintain normal blood pressure
circulatory shock
what does the baroreceptor reflex result in?
a decrease in BP
what is a consequence of circulatory shock?
tissues suffer damage due to lack of oxygen
in nervous regulation of blood vessels what plays a major role in regulating the frequency of action potentials in nerve fibers that innervate blood vessels?
the vasomotor center within the medulla oblongata
what is capillaries the only vessel in the body to do?
allow exchange between blood and environment
if you have too little carbon dioxide what happens to your blood pressure?
it goes down
why are capillaries able to allow for exchange between blood and environment?
because their walls are so thin
how does the baroreceptor reflex work?
an increase in BP increases parasympathetic stimulation of the heart and decreases sympathetic stimulation of the heart and blood vessels
what is true of blood flow in the aorta and capillaries ?
velocity of blood flow is the greatest but the total cross sectional area is small and with capillaries the cross sectional area is large but the velocity of blood flow is low
what is the precapillary sphincter made of?
smooth muscle
what else does ADH increase? (2) (WL)
1) water reabsorption by kidneys
2) large amounts of ADH result in vasoconstriction
the pressure at which a sound is first heart
systolic pressure
what happens to blood pressure when heart rate goes down?
bloop pressure goes down
where do veins of the hepatic portal system converge?
on the hepatic portal vein
what are the results from the renin-angiotensin-aldosterone mechanis? (4) (VIDC)
1) vasoconstriction
2) increased water reabsorption
3) decreased urine volume
4) changes that maintain blood pressure
what does a decrease in blood pressure do for sympathetic stimulation of the heart and blood vessels?
increases it
what does the increased sympathetic stimulation of the adrenal medulla result in?
epinephrine and some norepinephrine secretion
what opens and closes depending on the need of the tissue?
precapillary sphincter
hardening of the arteries consists of degenerative changes in arteries that make them less elastic
arteriosclerosis
what are the mechanisms used to control human blood pressure? (6) (NBACRP)
1) nervous regulation of blood vessels
2) baroreceptor reflex
3) adrenal medullary mechanism
4) chemoreceptor reflex
5) renin-angiotensin-aldosterone mechanism
6) pH and gases
what does phlebitis result from?
blood flow in the veins becoming sufficiently stagnant (not moving) that the blood clots
helps regulate blood pressure by altering blood volume
renin-angiotensin-aldosterone mechanism
what are 3 things that can change from blood pressure?
1) Heart rate
2) vessel size
3) blood volume
what type of cell is the tunica media?
muscle cell
what is varicose veins further encouraged by?
activities that increase pressure in veins such as pregnancy or standing for prolonged period of time
natural communication direct or indirect between two blood vessels or other tubular structures. an opening created by surgery, trauma or disease between two or more normally separate spaces or organs
anastamoses
what is the tunica media of muscular arteries made up of?
smooth muscle
what can the antidiuretic hormone (Vasopressin) mechanism decrease and what does that result in?
BP and results in ADH secretion
what is a major regulatory mechanism that is part of long term regulation of BP?
renin-angiotensisn-aldosterone mechanism
what system controls blood volume?
endocrine system
when the net osmotic pressure is subtracted from the net hydrostatic pressure at the venous end what is the result?
a negative net filtration pressure
what are most blood vessels innervated by?
sympathetic nerve fibers
how does renin-angiotensin-aldosterone mechanism control blood pressure?
the kidneys detect decreased BP and increase renin secretion
even though veins have the same 3 layers what are some differences about veins?
1) less tunica media
2) less round
3) higher diameter lumen
if bloods squirts out what does that mean?
a severed artery
how does the adrenal medullary mechanism work?
increased sympathetic stimulation of adrenal medulla
what is the function of precapillary sphincters?
they regulate blood flow through the capillaries
how does the chemoreceptor reflex work?
and increase in carbon dioxide and a decrease in pH and oxygen result in an increased heart rate and vasoconstriction
what do hepatic veins carry?
blood from capillaries in the liver to the inferior vena cava.
when ADH increases water absorbtion by kidneys and vasoconstriction occurs what do these changes maintain?
Blood pressure
the deposition of material in the walls of the arteries to form distinct plaques.
artherosclerosis
what does a decrease in blood pressure do to parasympathetic stimulation of the heart?
it decreases it
what exists between the inside and outside of capillaries at their arterial and venous ends?
pressure differences
what are 2 types of capillaries? (2) (CF)
1) continuous (most common)
2) fenestrated (have holes)
high blood pressure with a systolic BP greater than 140mm Hg and a diastolic pressure greater than 90 mm Hg
hypertension
what happens to blood pressure when heart rate goes up?
blood pressure goes up
what happens to blood flow when precapillary sphincters dilate?
it increases
do arteries and veins have semilunar valves?
veins do, arteries don’t
reduced blood to an area of the body
ischemia
tissue death caused by a reduction in or loss of blood supply
gangrene
approximately how much of the fluid leaves the capillary at its arterial end reenters the capillary at the venous end?
nine-tenths
what are some characteristis of muscular arteries?
1) any artery without a name that isn’t elastic
2) up to .5 cm
3) thicker tunica media
what does the hepatic portal system being as?
capillary beds in the stomach, spleen, pancreas, small intestine and large intestine
