Chapter 21, the cardiovascular the heart

The heart is often described as four-chamber pump, but functionally it acts as what?

A two-chamber pump (right and left pump)

What color is used to represent the right side of the heart?

Blue (deoxygenated blood)

What color is used to represent the left side of the heart?

Red (oxygenated blood)

What kind of vessels exit the ventricles?

Only arteries 

What is it called when the heart becomes as large as a soccer ball?

Cardiomyopathy

What kind of vessels enter the atria?

Only veins

What circuit is associated with the right side of the heart?

The pulmonary circuit

What circuit is associated with the left side of the heart?

The systemic circuit

What is the visceral layer of the pericardium also called and what does it cover?

Epicardium: it covers the outer surface of the heart

What layer of the heart contains intercalated discs?

The myocardium (heart muscle)

What layer lines the chambers of the heart?

The endocardium

Which part of the heart is superior?

the base

Which part of the heart is inferior?

the apex

What is the coronary sinus?

A vessel that collects blood from the heart muscle and empties it into the right atrium

Where does the coronary sinus drain?

Into the right atrium

What are the two major veins entering the right atrium?

Superior vena cava and inferior vena cava

What major artery branches off the aorta to supply the right arm and head?

The brachiocephalic trunk

What major arteries branch from the aorta on the left side?

The left common carotid artery and left subclavian artery

What fetal structure connects oxygenated and deoxygenated blood in the womb and later becomes the ligamentum arteriosum?

The ductus arteriosus

What is the first branch off the aorta that nourishes the heart?

The coronary arteries

Where does deoxygenated blood from the heart muscle drain?

Into the coronary sinus

The coronary sinus empties into the chamber?

The right atrium

Which two major veins also enter the right atrium along with the coronary sinus?

The superior vena cava and Inferior vena cava

What are the tricuspid and mitral valves attached to?

Chordae tendineae (heart strings)

What do the chordae tendineae connect to?

Papillary muscles in the ventricles

What do papillary muscles help prevent?

Valves prolapse (they keep atrioventricular valves closed during ventricular contractions)

Which valves have NO chordae tendineae?

The pulmonary veins and aortic valve (the semilunar valves)

What are trabeculae carneae?

Meaty ridges of muscle inside the ventricles

What are pectinate muscles found?

Mainly in the right atrium

Where are the papillary muscles found?

In both ventricles

Which valve is located between the right atrium and right ventricle?

The tricuspid valve

Which valve is located between the left atrium and left ventricle ?

The mitral (bicuspid) valve

What is the function of the moderator band in the right ventricle?

Ensures both ventricles contract simultaneously

Do the atria contract together?

yes, both contract simultaneously

How big is a baby’s heart

about the size of a walnut 

Where does the right ventricle send blood?

To the lungs (via the pulmonary artery/trunk)

Where does the left ventricle send blood?

To the rest of the body (systemic circulation)

What does the heart function as?

A vessel that either sends blood out or receives blood

How many pulmonary veins enter the left atrium?

four pulmonary veins 

What is special about cardiac muscles electrical properties?

It has automaticity, can conduct its own electrical impulses without external nervous system input

What does the sinoatrial node do?

Acts as the heart’s natural pacemaker, generating electrical impulses that spread through the atria

What is the AV node responsible for?

Delaying the electrical signal before passing it to the ventricles, ensuring coordinated contractions

Which structure carries electrical impulses into the ventricles?

The purkinje fibers

What do papillary muscles and chordae tendineae help prevent?

Valves prolapse during ventricular contraction

What nervous system can slow down the heart?

The parasympathetic nervous system

Which cranial nerves provide parasympathetic input?

Cranial nerves 3,7,9, and 10

Which nerve primarily slows the heart rate?

the vagus nerve (cranial nerve 10)

What effect does sympathetic activation have on the heart?

It increases heart rate and contactility

What type of signal does the sympathetic system use to speed up the heart?

Norepinephrine and epinephrine