Anatomy Final (Chapter 22)

It is the _____________ that permits the compression necessary to pump large volumes of blood out of the ventricles.

arrangement of cardiac muscle in the heart wall

The beginning of the cardiac cycle is when the

atria contract

In an EKG, the P wave is generated when the

atria depolarize

The papillary muscles attach to the cusps of the atrioventricular valves by means of the

chordae tendineae.

The chordae tendineae are made out of

collagen fibers

Cardiac muscle fibers

contract as a single unit.

The atria are separated from the ventricles externally by the

coronary sulcus.

The left and right coronary arteries travel within the

coronary sulcus.

During early ventricular systole the atria are in

diastole.

Which describes the endocardium?

has single layer of epithelium, has layer of areolar connective tissue, epithelial cells are squamous

Sympathetic innervation of the heart

increases the heart rate, increases the force of contractions

The foramen ovale is actually an opening in the

interatrial septum

The cell-to-cell contacts of the cardiac muscle fibers are called

intercalated discs.

Which analogy fits the human heart?

it is like a double pump, each working side by side with the other

The base of the heart is formed primarily by the

left atrium

The serous fluid within the pericardial cavity works to

lubricate the membranes of the serous pericardium.

The trabeculae carneae in the left ventricle are ____________ in the right ventricle.

more prominent than

The layer of the heart wall composed of cardiac muscle tissue is the

myocardium.

For ___________ of the cardiac cycle, all four chambers are in diastole together.

one-half

The heart valves

permit the passage of blood in one direction.

As blood is pumped into the arterial trunks past the semilunar valves, it

pushes against the cusps, forcing the valves open.

In an EKG, the T wave denotes

repolarization of ventricles

Which heart chambers pump deoxygenated blood?

right atrium and right ventricle

The right border of the heart is supplied by the

right marginal artery

The function of the coronary sinus is to

take blood from the coronary circulation to the right atrium

During ventricular systole

the semilunar valves open and the AV valves close

The arteries and veins that leave and enter the heart are called the great vessels because

they have relatively large diameters.

Development of the heart commences in the _______ week.

third

The internal wall surface of each ventricle displays large, smooth, irregular muscular ridges called

trabeculae carneae.

Typically, there are __________ papillary muscles that project from the wall of the left ventricle and attach to the chordae tendineae that support the left AV valve.

two

The inferior chambers of the heart are the

ventricles

One example of cardiac arrhythmia is _________, in which a rapid, repetitious movement of the ventricular muscle replaces normal contractions.

ventricular fibrillation

The epicardium is another name for the

visceral layer of serous pericardium

During a cardiac cycle, how many of the four chambers contract at any one time?

2

How many half-moon shaped, pocketlike cusps are found in each semilunar valve?

3

Which values are reasonable for a healthy, 80 kilogram resting adult?

5.25 liters of blood pumped per ventricle per minute; 108,000 beats per day

Of the four "normal" heart sounds, the initial "lubb" sound is heard when the

AV valves close.

Which does not drain into the coronary sinus?

Anterior interventricular vein

Which structure marks the end of the left ventricle and the entrance to the aorta?

Aortic semilunar valve

Which valve prevents the backflow of blood into the left ventricle when the ventricles relax?

Aortic semilunar valve

Parasympathetic innervation of the heart occurs via

CN X.

Which action causes the closure of the right atrioventricular valve?

Contraction of the right ventricle

Which bears a close structural relationship with the fossa ovalis?

Foramen ovale

Which correctly describes the heart's apex?

Projects slightly anteroinferiorly toward the left side of the body

Which of the cardiovascular system's circuits has deoxygenated blood in its arteries?

Pulmonary circuit

Which carries oxygenated blood from the lungs to the heart?

Pulmonary veins

Which pair is located more anteriorly in a heart in normal position?

Right atrium and right ventricle

What part of the cardiac conduction system is located in the posterior wall of the right atrium, adjacent to the entrance of the superior vena cava?

SA node

The sequence of events in the transmission of an impulse through the heart muscle is

SA node, through the atria, AV node, AV bundle, bundle branches, Purkinje fibers, through the ventricles

Which are functions performed by the fibrous skeleton of the heart?

Separates the atria and ventricles, Anchors the heart valves, Provides electrical insulation between the atria and ventricles, Provides the framework for the attachment of the myocardium

The left atrium and left ventricle are part of which circuit of the cardiovascular system?

Systemic circuit

Which circuit of the cardiovascular system is responsible for sending blood to the kidneys, stomach, and pelvic regions?

Systemic circuit

Sympathetic innervation of the heart arises from the ________ segments of the spinal cord.

T1 T5

Which may predispose one to inadequate coronary blood flow?

Tachycardia

Which are differences between cardiac muscle tissue and skeletal muscle tissue?

The sarcoplasmic reticulum in cardiac muscle is less extensive. Cardiac muscle has intercalated discs; skeletal muscle does not. Cardiac muscle has 1 or 2 nuclei per cell; skeletal muscle has multiple nuclei per cell.

During ventricular diastole

The semilunar valves close and the AV valves open

Which can be used to characterize blood flow in the human body?

There is a unidirectional blood flow. Arteries carry blood away from the heart. Veins carry blood toward the heart.

Which prenatal structure forms the ascending aorta and pulmonary trunk?

Truncus arteriosus

The cardiac cycle is

all the events involved with a single heart beat.

The great cardiac vein runs alongside the

anterior interventricular artery

Pectinate muscles are found on the

anterior wall of the right and left atria