Cardiac System

Which layer of the heart contains a lubricating fluid that reduces friction as the heart beats?

• Pericardium

• Endocardium

• Myocardium

Which would you focus on in order to judge the health of the ventricles?

• T wave

• P wave

• PR segment

• QRS complex

If the P wave on an EKG looks abnormal, which structures in the heart are likely damaged?

• SA/AV node

• Aortic valve

• Bundle of His

• Purkinje fibers

What does depolarization result in?

• relaxation

• contraction

• repulsion

• attraction

What is the second step to heart contraction?

• Atria contract

• ventricles contract

• depolarization of SA node

• Impulse spreads throughout the atria

A heart rate 100 bpm or above is called _______.

• bradycardia

• tachycardia

• arrhythmia

• fibrillation

Tags

NGSS.HS-LS1-3

A person's blood pressure is a reflection of: 

• lymphatic pressure.​

• arterial pressure.

• osmotic pressure.

• venous pressure.

Tags

NGSS.HS-LS1-3

The SA node fires at a rate of

• 40-60 bpm

• 80-90 bpm

• 60-80 bpm

• 60-100 bpm

The pointed, inferior portion of the heart, known as the ________ rests on the diaphragm and is oriented towards the left hip.

• base

• mediastinum

• apex

• pericardium

Which component of the cardiac conduction system is known as the natural pacemaker of the heart?

• Sinoatrial node

• Atrioventricular node

• AV bundle

• Purkinje fibers