Chapter 18 Quiz [Heart]

Hemorrhage with a large loss of blood causes... 1 - A lowering of blood pressure due to change in cardiac output 2 - A rise in blood pressure due to change in cardiac output 3 - No change in blood pressure but a slower heart rate 4 - No change in blood pressure but a change in respiration

1 - A lowering of blood pressure due to change in cardiac output

The second heart sound is heard during which phase of the cardiac cycle? 1 - Isovolumetric relaxation 2 - Ventricular filling 3 - Isovolumetric contraction 4 - Ventricular ejection

1 - Isovolumetric relaxation

Norepinephrine acts on the heart by _____. 1 - Decreasing heart contractility 2 - Blocking the action of calcium 3 - Causing a decrease in stroke volume 4 - Causing threshold to be reached more quickly

4 - Causing threshold to be reached more quickly

Normal heart sounds are caused by...

Closure of the heart valves.

If cardiac muscle is deprived of its normal blood supply, damage would primarily result from ________.

Decreased delivery of oxygen.

Which vessel(s) of the heart receive blood during right ventricular systole?

Pulmonary trunk.

The fact that the left ventricle of the heart is thicker than the right ventricle reveals that it ________.

Pumps blood against a greater resistance.

If the vagal nerves to the heart were cut, the result would be that...

The heart rate would increase by about 25 beats per minute.

A foramen ovale connects...

The two atria in the fetal heart.

The tricuspid valve is closed when...

The ventricle is in systole.

Compared to skeletal muscle, cardiac muscle... 1 - Cells are larger than skeletal muscle cells 2 - Has gap junctions that allow it to act as a functional syncytium 3 - Has more nuclei per cell 4 - Lacks striations

2 - Has gap junctions that allow it to act as a functional syncytium

Isovolumetric contraction ________. 1 - Occurs only in people with heart valve defects 2 - Refers to the short period during ventricular systole when the ventricles are completely closed chambers 3 - Occurs while the AV valves are open 4 - Occurs immediately after the aortic and pulmonary valves close

2 - Refers to the short period during ventricular systole when the ventricles are completely closed chambers

Select the correct statement about the function of myocardial cells: 1 - Each cardiac muscle cell is innervated by a sympathetic nerve ending so that the nervous system can increase heart rate. 2 - The heart reflects the presence of gap junctions and the activity of the hearts conduction system. 3 - The refractory period in skeletal muscle is much longer than that in cardiac muscle. 4 - The influx of potassium ions from extracellular sources is the initiating event in cardiac muscle contraction.

2 - The heart reflects the presence of gap junctions and the activity of the hearts conduction system.

Select the correct statement about cardiac output: 1 - Decreased venous return will result in increased end diastolic volume. 2 - If a semilunar valve were partially obstructed, the end systolic volume in the affected ventricle would be decreased. 3 - Stroke volume increases if end diastolic volume decreases. 4 - A slow heart rate increases end diastolic volume, stroke volume, and force of contraction.

4 - A slow heart rate increases end diastolic volume, stroke volume, and force of contraction.

Which of the following factors does not influence heart rate? 1 - Gender 2 - Age 3 - Body temperature 4 - Skin color

4 - Skin color

Damage to the ________ is referred to as heart block

AV node.

Commotio cordis is heart failure due to... - Mild electrical shock to the heart itself - Severe electrical shock to the body - Relatively mild blow to the chest that occurs during a vulnerable interval (2 ms) when the heart is repolarizing - Loss of blood from an artery

A relatively mild blow to the chest that occurs during a vulnerable interval (2 ms) when the heart is repolarizing

The term for pain associated with deficient blood delivery to the heart that may be caused by the transient spasm of coronary arteries is ________.

Angina pectoris.

The P wave of a normal electrocardiogram indicates ________.

Atrial depolarization.

The condition where fluid accumulation in the pericardial cavity compresses the heart and limits its ability to pump blood is called ________.

Cardiac tamponade.

Blood within the pulmonary veins returns to the ________.

Left atrium.

During the period of ventricular filling, blood flows...

Mostly passively through the atria and open AV valves into ventricles.

Which vessels receives blood during ventricular systole?

The aorta and pulmonary trunk.