A&P Chapter 19

After a myocardial infarction, a patient is diagnosed with a damaged atrioventricular bundle. Is this serious? How would this condition be treated?

This would disrupt the electrical framework of the heart. Patient would need a secondary pacemaker that would act in response to the SA node thus completing the cycle.

Prevents backflow of blood from right ventricle into right atrium.

Tricuspid valve

Relaxation phase of the ventricles.

Ventricular diastole

Contraction phase of the ventricles.

Ventricular systole

To which side of the body is the apex pointed? a)At the midline b)To the left c)To the right d)Different for males and females e)Posteriorly

b)To the left

This electrical event represents repolarization of the ventricle. a)R wave b)Twave c)S wave d)P wave e)Q wave

b)Twave

This term refers to the period of time during a cardiac cycle when contraction occurs and blood pressure rises. a)filling b)systole c)repolarization d)diastole e)fibrillation

b)systole

Valves closed during ventricular systole.

AV

Valves open during ventricular diastole.

AV

Valves closing to produce first heart sound.

AV valves

Prevents backflow of blood from aorta into left ventricle.

Aortic semilunar valve

A patient that is having a heart attack is often accompanied with atrial or ventricular fibrillation. What is fibrillation and how could you stop it?

Fibrillation is erratic electrical activity in the heart. You can defibrillate the heart, send an electrical shock to reset the correct rhythm.

Separates ventricles.

Interventricular septum

Receives blood from pulmonary veins.

Left atrium

Pumps blood into aorta.

Left ventricle

What is an Electrocardiogram? What does the P, QRS, and T waves represent?

Measures the electrical activity of the heart. P wave measures the SA node and movement of the AP in the atria QRS measures the AV node and movement of the AP in the ventricles T wave measures the ability of the ventricles to recover from the AP

Where is the cardiovascular center?

Medulla oblongata

Prevents backflow of blood from left ventricle into left atrium.

Mitral valve

How would you describe the behavior of the atria and ventricles during one cardiac cycle?

One cycle: Both atria contract followed by both ventricles contraction, the entire heart rests as the heart fills with blood

Describe two differences between fetal circulation and adult circulation. Why do those differences exist?

Oval foramen and ductus arteriosis: Design to bypass the pulmonary circuit as the lungs of a fetus are not yet operational

What is Afterload? Why does having hypertension increase afterload?

Pressure that must be overcome to push blood out of the ventricles. If you have hypertension your ventricle has to work harder to push the same amount of blood out...usually end up lowering your ESV thus lowering SV

Prevents backflow of blood from pulmonary trunk into right ventricle.

Pulmonary semilunar valve

Describe systemic and pulmonary circulation.

Pulmonary: Blood from right side of heart (oxygen poor) to the lungs to bring in oxygen, lose carbon dioxide, and return to the left side of the heart (oxygen rich) Systemic: Blood leaves the left side of heart (oxygen rich) transported to entire body for gas exchange, oxygen out of blood while moving carbon dioxide in, blood returns to right side of heart (oxygen poor)

Receives blood from venae cavae.

Right atrium

Pumps blood into pulmonary trunk.

Right ventricle

What is the equation for CO (cardiac output)?

SV x HR

Describe the histology of cardiac muscle tissue.

Shorter fibers, one nucleus per muscle fiber, lots of mitochondria for aerobic cellular respiration, intercalacted disks to promote a smooth contraction, branched, and involuntary

Which of the following consists of inelastic dense irregular connective tissue? a)Parietal layer of pericardium b)Serous pericardium c)Fibrous pericardium d)Epicardium e)Pericardial cavity

c)Fibrous pericardium

This part of the brain regulates heart rate. a)Cardiac accelerator nerves b)Chemoreceptors c)Medulla oblongata d)Vagus nerve e)Proprioceptors

c)Medulla oblongata

Which layer consists of cardiac muscle tissue? a)Epicardium b)Pericardium c)Myocardium d)Endocardium e)Hypocardium

c)Myocardium

Which of the below valves prevents blood from flowing back from the lungs? a)Tricuspid valve b)Bicuspid valve c)Pulmonary valve d)Aortic valve e)Pulmonary vein

c)Pulmonary valve

This heart structure carries deoxygenated blood. a)Left atrium and ventricle b)Left atrium only c)Right atrium and ventricle d)Right ventricle only e)Left atrium and right ventricle

c)Right atrium and ventricle

Through which structure does blood pass from the right atrium to the right ventricle? a)Bicuspid valve b)Interventricular septum c)Tricuspid valve d)Mitral valve e)Ascending aorta

c)Tricuspid valve

Which of the below factors would increase Stroke volume? a)increased preload, increased afterload, increased contractility b)decreased preload, decreased afterload, decreased contractility c)increased preload, decreased afterload, increased contractility d)decreased preload, increased afterload, increased contractility e)increased preload, increased afterload, decreased contractility

c)increased preload, decreased afterload, increased contractility

Valves closed during ventricular diastole.

semilunar

Valves closing to produce second heart sound.

semilunar

Valves open during ventricular systole.

semilunar

What is End Systolic Volume?

volume of blood in ventricle after contraction

What is End Diastolic Volume?

volume of blood in ventricle at end of filling

Gabriel, a heroin addict, feels tired, is weak and feverish, and has vague aches and pains. Terrified that he has AIDS, he goes to a doctor and is informed that he is suffering not from AIDS, but from a heart murmur accompanied by endocarditis. What is the most likely way the Gabriel contracted endocarditis?

As a heroin addict, he has probably injected himself with the bacteria that has now taken up residence by the heart vavle.

Restrain cusps of A-V valves.

Chordae tendinaeae

What is coronary circulation?

Circulation to the heart muscle

Describe what happens to Cardiac Output in the following situations. Be as specific as possible. a. Your sympathetic division of the nervous system increases its signal on the heart. b. Your parasympathetic division increases its signal on the heart. c. You increase your venous return due to exercise. d. A decrease in available calcium.

Describe what happens to Cardiac Output in the following situations. Be as specific as possible. a. Your sympathetic division of the nervous system increases its signal on the heart. Increases HR thus increasing CO b. Your parasympathetic division increases its signal on the heart. Decreases your HR thus decreasing CO c. You increase your venous return due to exercise. More blood flows into heart thus increasing yourEDV and SV thus increasing CO d. A decrease in available calcium. Your contractility decreases thus a lower ESV and a lower SV thus decreasing CO

Name and describe two ways to prevent further myocardial infarctions?

Exercise and a diet low in saturated fats and cholesterol.

The _________ is the external layer of the heart that is thin and transparent. The ______ makes up 95% of the heart and is composed of ________ muscle. The inner layer, ________ lines the inside of the heart and composes the _________.

The ( epicardium)is the external layer of the heart that is thin and transparent. The (myocardium)makes up 95% of the heart and is composed of ( cardiac )muscle. The inner layer, (endocardium )lines the inside of the heart and composes the ( heart valves).

The __________ node generates impulses at a rate of _______ beats per minute. The impulse travels across the ______ and pauses at the ___________ node. From there, the impulse travels down the interventricular septum via ____________ and spreads to both _______ via the _______ fibers. The _______ nervous system can influence the speed at which the pacemaker works. The _________ division, fight or flight, will speed up the rate of heart contractions while the _________ division, rest and digest, will slow it down. _______is the normal pulse rate for an adult at rest.

The (Sinoatrial (SA) )node generates impulses at a rate of (100)beats per minute. The impulse travels across the (atria)and pauses at the (Atrioventricular (AV))node. From there, the impulse travels down the interventricular septum via (ventricular bundles)and spreads to both (ventricles)via the (purkinje)fibers. The (autonomic )nervous system can influence the speed at which the pacemaker works. The (sympathetic)division, fight or flight, will speed up the rate of heart contractions while the (parasympathetic)division, rest and digest, will slow it down. (60-100)is the normal pulse rate for an adult at rest.

What pressure must be overcome in the left ventricle during ventricular systole in order to keep blood flowing?

The afterload

Describe the location of the heart.

The apex of the heart is pointing left with 2/3 the mass left of the midline. As a result the left lung is 10% smaller than the right.

To temporally treat tachycardia and restore the normal resting rhythm, a physician may massage a patient's carotid artery near the angle of the mandible. Propose a mechanism by which this treatment would have the desired effect.

The baroreceptors in the carotid artery measured a higher blood pressure. To lower the BP the brain decreases your HR to lower CO thus lowering BP

Gerald recently visited the dentist to have his teeth cleaned and checked. During the cleaning process, Gerald had some bleeding form his gums. A couple of days later, Gerald developed a fever, rapid heartbeat, sweating, and chills. He visited his family physician, who detected a slight heart murmur. Gerald was given antibiotics and continued to have his heart monitored. How was Gerald's dental visit related to his illness?

The bleeding at the gums opened a gateway for bacteria in the mouth to travel into the body. That bacteria attached to the heart valve.

The heart is surrounded by the _______ The outer layer is composed of dense irregular connective tissue and is called the _________ The inner layer, _________ is a double layer composed of the _________ that is fused to the outer layer, and the ________ that is fused to the heart. The fused layer to heart is also known as the ________.

The heart is surrounded by the (pericardium ) The outer layer is composed of dense irregular connective tissue and is called the (fibrous pericardium)The inner layer, (serous pericardium )is a double layer composed of the (parietal)that is fused to the outer layer, and the (visceral)that is fused to the heart. The fused layer to heart is also known as the (epicardium).

What is the arrangement of systemic and pulmonary circulations in terms of how the heart works them both?

The left side of the heart is the pump for the systemic circulation and the right side of the heart is the pump for the pulmonary circulation.

Explain the reason that the muscular wall of the left ventricle is thicker than the right?

The left ventricle muscular wall if thicker because it has to pump blood great distances to all other parts of the body at higher pressure and the resistance to flow is small.

Discuss how the Frank-Starling law of the heart helps to explain the influence of venous return on stroke volume.

The more the heart fills with blood (increasing EDV) during diastole, the greater the force of contraction during systole. This will increase SV which means VR will have to increase to deal with the faster rate of blood movement.

Heather, a newborn baby, needs surgery because she was born with an aorta that arises from the right ventricle and a pulmonary trunk that issues from the left ventricle, a condition called transposition of the great vessels. What are the physiological consequences of this defect?

Your blood flow circuits would not function properly. You would be pumping oxygen poor blood into the aorta and body thus starving the body of much needed oxygen.

This is the volume of blood ejected from the left ventricle into the aorta each minute. a)Cardiac output b)Cardiac input c)Stroke volume d)Heart rate e)Auscultation

a)Cardiac output

This is the layer that protects the heart. a)Epicardium b)Parietal layer c)Myocardial tissue d)Mediastinum e)Endocardium

a)Epicardium

As each ventricle contracts where does blood move? a)Into an artery b)Into the apex c)Into a vein d)Through an atrioventricular valve e)Through the apex

a)Into an artery

What is stroke volume?

amount of blood ejected from a ventricle

What is cardiac output?

amount of blood ejected from heart per minute

What is Venous Return?

amount of blood returning to the heart

The second heart sound represents which of the below events? a)Valvular stenosis b)Semilunar valves opening c)Atrioventricular valves closing d) Semilunar valves closing e)Atrioventricular valves opening

d) Semilunar valves closing

From the left ventricle, where does blood pass? a)Right atrium b)Right ventricle c)Bicuspid valve d)Aortic semilunar valve e)Pulmonary trunk

d)Aortic semilunar

This is a network of specialized cardiac muscle fibers that provide a path for each cycle of cardiac excitation to progress through the heart. a)Pacemaker b)Sinoatrial node c)Purkinje fibers d)Conduction system e)Bundle of His

d)Conduction system

This electrical event triggers contraction of the atria. a)R wave b)Twave c)S wave d)P wave e)Q wave

d)P wave

This is used to reduce the friction between membranes of the heart. a)Epicardium b)Endocardium layer c)Pericardium d)Pericardial (serous) fluid e)Pericardial cavity

d)Pericardial (serous) fluid

This is a the correct sequence of structures that allows the normal sequence of excitation to progress through the heart. a)Bundle of His, Purkinje fibers, Atrioventricular (AV) node b)Sinoatrial (SA), Purkinje fibers, AV node, Bundle of His c)Purkinje fibers, AV node, SA node, Bundle of His d)SA node, AV node, Bundle of His, Purkinje fibers e)Bundle of His, SA node, AV node, Purkinje fibers

d)SA node, AV node, Bundle of His, Purkinje fibers

This part of the heart can initiate a contraction and can set a constant heart rate of about 100 beats per minute. a)Cardiac accelerator nerves b)Chemoreceptors c)Cardiovascular center d)Sinoatrial valve e)Proprioceptors

d)Sinoatrial valve

As each atrium contracts where does blood move? a)Into an auricle b)Into an artery c)Into a vein d)Through an atrioventricular valve e)Through a semilunar valve

d)Through an atrioventricular valve

In a fetus, this structure temporarily shunts blood from the pulmonary trunk into the aorta. a)Fossa ovalis b)Foramen ovale c)Trabeculae carnae d)Descending aorta e)Ductus arteriosus

e)Ductus arteriosus