Ch 14: Cardiac Output, Blood Flow, And Blood Pressure Flashcards
Opening of K gates will slow the heartbeat. T/F.
True
The first heart sound is associated with the diastole. T/F.
False
Resting cardiac muscle cells have a resting potential of ____ millivolts.
-90
The plateau of the cardiac muscle action potential is due to prolonged movement of ____ ions.
Calcium
The _____ wave of the EKG represents the ventricular repolarization.
T
All blood vessels are lined with?
Endothelial cells
Cardiac output is equal to?
Stroke volume x cardiac rate
The average heart rate is?
70 bpm
The average stroke volume is?
70-80 ml/beat
The average cardiac output is?
5,500 ml/minute
Spontaneous _____ occurs at SA node when HCN channels open, allowing Na+ in.
Depolarization
Sympathetic norepinephrine (vagus nerve) and adrenal epinephrine keep HCN channels open, _____ heart rate.
Increasing
Parasympathetic _______ opens K+ channels, slowing heart rate.
Acetylcholine
The ____ is the volume of blood in the ventricles at the end of diastole. It is sometimes called preload. The stroke volume increases with increased EDV.
End diastolic volume
The ____ is the frictional resistance in the arteries.
Total peripheral resistance
The ____ is the strength of ventricular contraction.
Contractility
What law increased EDV results in increased contractility and thus increased stroke volume?
Frank-Starling Law
Increased EDV stretch the myocardium, which increases ____ strength.
Contraction
Which control of contractility has sympathetic norepinephrine and adrenal epinephrine that can increase contractility by making more Ca2+ available to sarcomeres?
Extrinsic
_____ is controlled by factors that affect venous return, like total blood volume, and venous pressure.
End diastolic volume
___ of our body water is found in the cells.
2/3
Of the remaining, 80% exists in interstitial spaces and 20% is in the _______.
Blood plasma
Urine formation and water intake (drinking) also play a role in _____.
Blood volume
_____ is the hydrostatic pressure of the blood in the capillaries minus the hydrostatic pressure of the fluid outside the capillaries.
Net filtration pressure
______ is due to proteins dissolved in fluids.
Colloid osmotic pressure
____ is a combination of hydrostatic pressure and oncotic pressure that predicts movement of fluid across capillary membranes.
Starling forces
Starling forces predict the movement of fluid out of the capillaries at the _____ and into the capillaries at the ____.
Arteriole end
Venule end
____ is excessive accumulations of interstitial fluids.
Edema
The formation of urine beings with filtration of fluid through capillaries in the kidneys called ______.
Glomeruli
An ______ is produced by hypothalamus and released when osmoreceptors there detect increased plasma osmolarity.
Antidiuretic hormone
Increased water intake and decreased urine formation increase _____.
Blood volume
____ is secreted by adrenal cortex indirectly when blood volume and pressure are reduced.
Aldosterone
When blood pressure is low, cells in the kidneys secrets the enzyme renin is known as?
Renin-angiotensin-aldosterone system
______ raises in blood pressure because of the vasoconstriction of small arteries and arterioles, stimulate thirst center in hypothalamus, and stimulates production of aldosterone in adrenal cortex.
Angiotensin II
_____ is produced by the atria of the heart when stretched.
Atrial natriuretic peptide
_____ is distributed unequally to different organs due to unequal resistance to blood flow through the organs.
Cardiac output
_____ of arterioles provides the greatest resistance to blood flow and can redirect flow to/from particular organs.
Vasoconstriction
The _____ increase total peripheral resistance through release of norepinephrine onto smooth muscle of arterioles in the viscera and skin to stimulate vasoconstriction.
Sympathetic nerves
____ is released onto skeletal muscles, resulting in increased vasodilation to these tissues.
Acetylcholine
Molecules produced by one tissue control another tissue with the same organ is called?
Paracrine control
Smooth muscle relaxation influenced by bradykinin, nitric oxide, and prostaglandin I2 to produce ______.
Vasodilation
_______ stimulates smooth muscle contraction to produce vasoconstriction and raise total peripheral resistance.
Endothelin-1
_____ regulation is used by some organs (brain and kidney) to promote constant blood flow when there is fluctuation of blood pressure.
Intrinsic
Vascular smooth muscle responds to change in arterial blood pressure know as what?
Myogenic control mechanisms
The _______ supply blood to a massive number of capillaries.
Coronary arteries
Unlike most organs, blood flow is restricted during _____.
Systole
_____ tissue also has lots of mitochondria and respiratory enzymes, thus is metabolically very active.
Cardiac
During exercise, the coronary arteries _____ blood flow from 80 ml to 400 ml/minute/100 g tissue.
Increase
______ from sympathetic nerve fibers stimulate vasoconstriction, raising vascular resistance at rest.
Norepinephrine
_____ stimulates vasodilation and thus vascular resistance during exercise.
Adrenal epinephrine
_____ is enhanced by intrinsic metabolic control mechanisms.
Vasodilation
Even at rest, ____ muscles still receive 20-25% of the body’s blood supply.
Skeletal
_____ can increase 5X due to increased cardiac rate.
Cardiac output
______ can increase some due to increased venous return.
Stroke volume
In _____ the brain cannot tolerate much variation in blood flow.
Cerebral circulation
When blood pressure legally, cerebral vessels automatically ______.
Dilate
When blood pressure rises, cerebral vessels automatically _____.
Constrict
The ____ can tolerate the greatest fluctuations in blood flow.
Skin
The skin helps control the body temperature in a changing environment by regulating blood flow is called?
Thermoregulation
The ____ shunts blood from arterioles directly to the venules.
Arteriovenous anastomoses
______ is affected by blood volume/stroke volume, total peripheral resistance, and cardiac rate.
Blood pressure
______ blood pressure is low because of the large cross sectional area.
Capillary
_____ can control blood volume and thus stroke volume.
Kidneys
The _________ stimulates vasoconstriction of arterioles and increased cardiac output.
Sympathoadrenal system
______ is activated by changes in the blood pressure detected by baroreceptors in the aortic arch and carotid sinuses.
Baroreceptor reflex
The _____ center controls vasodilation a d contraction.
Vasomotor
The cardiac center controls ______.
Heart rate
Fall in blood pressure means an increase in _____ and decrease in ____ activity, resulting in increased heart rate and total peripheral resistance.
Sympathetic
Parasympathetic
______ are activated by increased venous return to stimulate tachycardia and inhibit ADH release.
Atrial stretch reflexes
The blood pressure is measured in mmHg by an instrument called a _______.
Sphygmomanometer
A blood pressure cuff produces turbulent flow of blood in the brachial artery, which can be heard using a stethoscope is called sounds of _______.
Korotkoff
The cuff is first inflated to beyond systolic blood pressure to pinch off an artery. As pressure is released, the _____ sound is heard at systole and a reading can be taken.
First
The ____ Korotkoff sound is heard when the pressure in the cuff reaches diastolic pressure and a second reading can be taken.
Last
The average blood pressure is ____.
120/80
You you are taking someone’s pulse, you are measuring their ____.
Heart rate
The difference between blood pressure at systole and at diastole is the ______.
Pulse pressure
The average pressure in the arteries in one cardiac cycle is the ______.
Mean arterial pressure
_____ is high blood pressure.
Hypertension
____ of Americans have hypertension.
20%
___ can increase the risk of cardiac diseases and stroke.
Hypertension
Most people fall into the category of _____.
Essential hypertension
The dangers of _____ are vascular damage within the organs, especially dangerous in the cerebral vessels and leading to stroke.
Hypertension
_______ occurs when there is inadequate blood flow to match oxygen usage in the tissues.
Circulatory shock
______ is due to low blood volume from an injury, dehydration, or burns.
Hypovolemic shock
Dangerously low blood pressure due to an infection is called?
Septic shock
Severe allergic reactions can cause _______ shock due to production of histamine and resulting vasodilation.
Anaphylactic
Spinal cord injury or anesthesis can cause ____ shock due to loss of sympathetic stimulation.
Neurogenic
Cardiac failure can cause _____ shock due to significant myocardial loss.
Cardiogenic
_______ occurs when cardiac output is not sufficient to maintain blood flow required by the body.
Congestive heart failure
What type of receptors do norepinephrine and epinephrine bind to in the heart?
B1- adrenergic
Acetylcholine bind to ____ receptors of the heart and causes the opening of ___ channels.
Muscarinic, K+
The cardiac control center of the _____ coordinates the autonomic innervation of the heart.
Medulla oblongata
Cardiac output would be increased by?
Positive chronotropic agents
Hydrostatic pressure is _____ and colloid osmotic pressure is _____ at the arterial end of a capillary.
Higher, lower
______ is a steroid hormone secreted by the adrenal cortex which stimulates kidney salt reabsorption in the kidneys.
Aldosterone
Angiotensin I is formed from the plasma protein ___ by the action of the enzyme ____.
Angiotensinogen, renin
Sweat glands can also secrete _____ that stimulates vasodilation of skin arterioles to help reduce body temperature.
Bradykinin
Which blood vessels have the highest cross-sectional area?
Capillaries
Which blood vessels have the lowest pressure?
Veins
Increased blood pressure stimulates?
Decreased sympathetic outflow to the heart
The last Korotkoff sound occurs when the blood pressure is equal to?
Diastolic pressure
The mean arterial pressure of a person with a blood pressure 128/68 would be?
88
Secondary hypertension may result from?
A renin secreting tumor
Cardiogenic shock can result from ?
Myocardial infarction
