Anatomy Study Guide

Trace the flow of blood in the heart, starting at the vena cava

SVC/IVC → right AV valve → right ventricle → pulmonary valve → pulmonary trunk → lungs → pulmonary veins → left atrium → left AV valve → left ventricle → aortic valve → aortic trunk → aorta → systemic circuit

ID the chamber that receives blood from the systemic circuit

Right atrium

ID the chamber that sends blood into the systemic circuit

Left ventricle

ID the valve that prevents backflow into the L. Atrium

Bicuspid/ left AV valve

ID the valve that prevents backward flow into the R. Atrium

Pulmonary valve

Shrink Jack, inject him into a mini submarine, into the femoral vein. Trace his path from the injection site to lungs

Femoral vein → common iliac vein → inferior vena cava → right atrium → right AV valve → right ventricle → pulmonary valve → pulmonary trunk → L/R pulmonary artery → L/R lung

The heart can generate its own heartbeat. This means it is

Autorhythmic

What cell generates the action potential in the heart

Pacemaker

How do pacemaker cells connect cardiomyocytes

Gap junction

How does cardiomyocytes receive the action potential

Gap junctions

Break down the word “cardiomyocyte.” Why does the cell need Ca++ to enter the cell?

Heart muscle cell. The cell needs calcium to enter the cell during contraction to have a muscle contraction

What is the purpose of the GHK equation

It is used to determine the normal membrane voltage of cardiomyocytes, pacemaker, and the threshold

Differentiate between equilibrium potential and the simplified GHK equation

The GHK equation calculates membrane voltage, accounting for all ions present. Equilibrium is for only one ion

Trace the path of the cardiac conduction system, and what the HR would be if the HR originated from each point

SA Node (100 bpm) → AV node (60 bpm) → Bundle of HIS (40-50 bpm) → Purkinjie fibers (15-30 bpm)

If my SA node stopped working, what would my average HR look like?

Around 60 bpm, because my AV node would kick in to help make heart beats

Why would I be unconscious if I lost function of both my SA node and my AV node?

My heart rate would be in the 40s-50s.

All parts of the conduction system are faithful followers; what part of the heart anatomy ensures this?

Gap junctions

Pace is always set by the ____ operating pacemaker

fastest

The heart is ____. But, the brain can tell the heart to speed up or slow down using the ____.

Aurothymic, autonomic nervous system

This system speeds up the heart through the use of norepinephrine

sympathetic nervous system

This system slows down the heart through the use of acetylcholine

parasympathetic nervous system

Why is Ach always released in small amounts (tonic inhibition)?

To maintain a normal BPM @ rest, or or else HR may be closer to the 100 bpm set by the SA node

This nerve is a type of parasympathetic nerve, and it’s neurotransmitter attaches to what receptors?

Vagus nerve, Muscarinic Ach Receptor (MAchR)

These fibers are a type of sympathetic nerve, and its neurotransmitters attach to what receptors in the heart

Cardiac sympathetic fibers, beta receptors

Anything that modifies Na+ will have an affect on HR, why?

Because voltage-gated Na+ channels are responsible for bringing the cell to a positive charge

How do you count the HR on an ECG

Count the R waves

Aortic Arch Baroreceptors

activates when pressure is too high

Carotid Sinus

Located in the head, activates when pressure is too high

Aortic Arch and Carotid Sinus, how do the connect

Connect to our brainstem and tell the rest of the body if the pressure is too high or too low. This allows our vessels to vasoconstrict (increase BP) or vasodilate (decrease BP)

Vasoconstriction

Higher BP

Vasodilation

Lower BP

Define blood vessels

Elastic arteries with thick cell wall, branch into muscular arteries

These blood vessels contain a lot of smooth muscle cells, collagen, and branch into small arteries

Muscular arteries

These blood vessels have lots of collagen and branch into arterioles

Small arteries

These blood vessels contain rings of smooth muscle that allow for control of where the blood goes. Branch into capillaries

Arterioles

1 red blood cell in diameter, very thin to allow for adequate oxygen exchange to the tissues. Combines to form arterioles and venules

Capillaries

These vessels have to work harder to bring blood from the feet to the heart. They also contain valves to stop blood from falling back down

Veins

What vessel supplies the kidneys

Renel artery

What vessel supplies the systemic circuit

Aorta

What valve does deoxygenated blood pass through the heart?

Right Av valve and pulmonary valve

What vessel drains the thigh

femoral vein

What vessel supplies the myocardium

coronary arteries

Hormone that increases HR

NE + Epi

What tissue layer lines the inside of the heart

Endocardium

What is the pacemaker of the heart

SA node

What chamber sends blood to the systemic circuit

Left ventricle

What vessel drains the liver

Hepatic vein

What vessel sends blood to the pulmonary circuit

pulmonary artery

What vessel supplies the brain

common carotid artery

What vessel drains the arm

Brachial vein/subclavian drain

What hormone is released to decrease HR

Ach

What kind of receptor is responsible for increase HR

Beta receptor

What hormone causes vasodilation

Histamine

Where is acetylcholine released from

Vagus/CN10

Define hypertension and provide numerical values

too high blood pressure. >130/>90

What is the inner most layer of the heart/ what tissue layer lines the atria/ventricles

endocardium

What structure separates the ventricles

intraventricular septum

What hormone causes vasodilation and decrease BP

Histamine

What vessel drains the myocardium

cardiac veins

What vessel drains the brain/head

internal and external jugular veins

What vessel supplies the lower extremity

common iliac artery

What vessel supplies the lower extremity

common iliac artery

What vessel carries blood to the heart from the systemic circuit

vena cava

Blockage of what vessel leads to an MI

Coronary artery blockage

What pressure represents ventricular relaxation

diastolic

What vessel carries blood from the GI tract to the liver

Hepatic portal vein