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Cardiac cycle
Cardiac output
Regulation of output
Blood vessels
Other
100

Ventricular Filling Phase

Low ventricular pressure allows blood to flow from the atria through the open AV valves.

100

What is preload

The initial stretching of the cardiac muscle fibers before contraction, influenced by the volume of blood in the ventricles (EDV)

100

The sympathetic nervous system releases what neurotransmitter

Norepinephrine, which increases heart rate (chronotropic effect) and contractility (inotropic effect), enhancing cardiac output during stress (fight or flight)

100

What is atherosclerosis and its effect

The formation of plaques in the tunica intima leads to narrowed arteries and reduced blood flow.

100

Blood pressure in the largest systemic arteries is highest during cardiac _______ and lowest during cardiac _______ and the difference between these two pressures is the _______.

systole; diastole; pulse pressure 

200

Isovolumetric Relaxation

Ventricles relax with no change in volume; SL valves close, and AV valves remain closed

200

What is afterload 

The resistance the ventricles must overcome to eject blood, with higher afterload leading to decreased stroke volume.

200

The parasympathetic nervous system releases what neurotransmitter

primarily through the vagus nerve, releases acetylcholine, which decreases heart rate and contractility, promoting a state of rest (rest and digest)

200

What are the 5 types of blood vessels

  • Arteries: Carry blood away from the heart; can be oxygenated (systemic circulation) or deoxygenated (pulmonary circulation). 
  • Arterioles: The smallest arteries that lead to capillaries; they regulate blood flow into capillary beds. 
  • Capillaries: The smallest blood vessels where the exchange of gases, nutrients, and waste occurs; they can form capillary beds to increase surface area for exchange. 
  • Venules: Collect blood from capillaries and transport it to veins. 
  • Veins: Carry blood back to the heart; they can also transport oxygenated or deoxygenated blood, depending on the circuit.
200

During the isovolumetric relaxation phase of the cardiac cycle, the _______ valves snap shut. You would expect to hear _______ during this phase.

 semilunar; S2

300

Isovolumetric Contraction

Ventricles contract with no change in volume; AV valves close, and SL valves remain closed.

300

How do you calculate cardiac output

HR x SV

300

Which hormones increase heart rate and contractility

epinephrine, norepinephrine, thyroid hormone, and glucagon

300

What are the layers of the tunica and their functions

  • Tunica Intima: Composed of simple squamous epithelium and basal lamina; reduces friction and allows smooth blood flow. 
  • Tunica Media: Contains circular smooth muscle; responsible for vasoconstriction and vasodilation, affecting blood pressure and flow. 
  • Tunica Externa: Provides structural support; made of collagen fibers that connect to the tunica media. 
300

The parasympathetic nervous system uses the neurotransmitter(s) _______ to interact with the heart, producing strong effects on _______ and weak effects on _______.

acetylcholine; heart rate; contractility

400

Ventricular Ejection Phase

High pressure in the ventricles opens the SL valves, allowing blood to flow into the arteries.

400

How do you calculate stroke volume

EDV - ESV

400

Aldosterone and ADH (antidiuretic hormone) do what 

increase blood volume by promoting water retention, which enhances preload and subsequently cardiac output.

400

Neural regulation of blood pressure

  • The sympathetic nervous system (SNS) increases blood pressure by enhancing heart rate and contractility, leading to increased cardiac output and peripheral resistance through vasoconstriction.
  • Conversely, the parasympathetic nervous system (PNS) decreases blood pressure by reducing heart rate and contractility, promoting vasodilation and decreasing peripheral resistance
400

Which of the following increase cardiac output through both chronotropic and inotropic effects? The SNS, glucagon, and aldosterone

The SNS and glucagon

500

Order of the Cardiac cycle phases

Ventricular filling, isovolumetric contraction, ventricular ejection, and isovolumetric relaxation 

500

The Frank-Starling Law

states that increased preload leads to stronger contractions, enhancing stroke volume

500

Atrial natriuretic peptide (ANP) has what effect

decreasing blood volume and cardiac output by promoting diuresis

500

Endocrine regulation of blood pressure (hormones and what they do)

  • Hormones such as epinephrine and norepinephrine increase cardiac output and peripheral resistance, thereby raising blood pressure.
  • Angiotensin II is a potent vasoconstrictor that increases blood pressure, while atrial natriuretic peptide (ANP) promotes vasodilation and decreases blood pressure.
500

If systemic blood pressure decreased, the _______ mechanism of autoregulation would stimulate the local arteriole feeding a capillary bed to _______, _______ perfusion back to the normal rate.

myogenic; vasodilate; increasing