Cardiac Output and Blood Flow Flashcards

Flashcards to review key concepts related to cardiac output, blood pressure regulation, and coronary blood flow.

At homeostasis, what does cardiac output equal?

Venous return

What two scientists are associated with the Frank-Starling Law?

Otto Frank and Ernest Starling

What is the relationship described by the Frank-Starling Law?

Relationship between stroke volume and end diastolic volume

How does increasing the volume of blood in the ventricles before contraction affect the stroke volume?

Stroke volume increases in response to the increase in blood volume in ventricles.

What happens to the cardiac muscle as the volume of blood increases?

Cardiac muscle stretches.

How does the stretching of cardiac muscle affect the force of contraction?

Cardiac muscle stretched increases the force of contraction.

What is cardiac output synchronized with?

Venous return

What is the name of the valve between the left atrium and left ventricle?

Mitral Valve

What is the name of the valve between the right atrium and right ventricle?

Tricuspid Valve

What type of tissue primarily makes up the tunica media of an artery?

Smooth muscle and elastic fibers

What are the factors that regulate blood pressure?

Heart rate, peripheral resistance, stroke volume, blood volume, blood viscosity, cardiac output

What is the formula for cardiac output?

Cardiac Output = Heart Rate x Stroke Volume

What is the formula for stroke volume?

Stroke Volume = End Diastolic Volume – End Systolic Volume

What is the relationship between blood pressure, cardiac output, and peripheral resistance?

Blood Pressure = Cardiac Output x Peripheral Resistance

Where are baroreceptors located?

Carotid arteries, aortic arch, and kidneys

What part of the brain is stimulated by baroreceptors?

Cardiac center in medulla

What division of the nervous system is stimulated by the medulla?

Sympathetic nervous system

What neurotransmitters are released by the sympathetic nervous system?

Norepinephrine and epinephrine

What receptors do epinephrine and norepinephrine bind to on the SA node of the heart?

Beta receptors

What happens to K+ leak gates as HR increases?

Close more times per minute triggering action potentials

What receptors do epinephrine and norepinephrine bind to on smooth muscle surrounding arteries to regulate peripheral resistance?

Alpha receptors

What ion diffuses into smooth muscle cells causing vasoconstriction?

Calcium

What is peripheral resistance defined as?

Friction of blood pushing against artery wall

How does end diastolic volume affect stroke volume?

Increase in EDV causes increase in stroke volume

How do Epi and Norepi affect respiratory muscles??

Cause the thoracic cage to expand and intrathoracic pressure to fall

What occurs to venous return when intrathoracic pressure falls?

Venous return increases

How does stretching of muscle affect actin and myosin?

Allows actin and myosin to align causing increased force of contraction

What cells in the kidneys are affected by Epi and Norepi to regulate blood volume?

Juxtaglomerular cells

What enzyme is released by JG cells?

Renin

What does renin bind to in the blood to create angiotensin I?

Angiotensinogen

What is the effect of sodium in the blood on water?

Water in ECF and ICF will move by osmosis into blood

What hormone is released by the hypothalamus in response to osmoreceptors?

Antidiuretic hormone

What hormone stimulates erythropoiesis?

Erythropoietin

What condition is defined as a sudden loss of blood pressure when standing?

Orthostatic hypotension

What reading is considered 'normal' blood pressure?

120/80 mmHg