Heart

Question 1

What is the heart, where is located, and what is its function?

Answer 1

A muscle organ

Slightly left center in the thoracic cavity

Pumps blood through blood vessels of the cardiovascular system

Question 2

Outline the structure of the heart.

Answer 2

3 Layers in the wall

4 chambers, upper atrium and lower ventricle on each side

4 ventricles to keep correct flow with no backflow

Question 3

Describe coronary circulation.

Answer 3

Made up of blood vessels that carry blood to and from the heart muscle cells

Two coronary arteries branch off to give oxygen rich blood to the heart

Question 4

Summarize oxygenated blood flow in, through, and out the heart.

Answer 4

• Blood enters Left Pulmonary Veins
• Left Pulmonary Veins to Left Atrium
• Left Atrium to Right Pulmonary Arteries
• Right Pulmonary Arteries to rest of body

Question 5

Summarize deoxygenated blood flow in, through, and out the heart.

Answer 5

• Low oxygen blood enters Vena Cava
• Vena Cava to Right Atrium
• Right Atrium to Left Pulmonary Arteries
• Left Pulmonary Arteries to Lungs

Question 6

Define the cardiac cycle and identify its two parts.

Answer 6

A complete heartbeat

Diastole: Atria contracts
Systole: Ventricle contracts

Question 7

Explain what controls the beating of the heart.

Answer 7

The heart’s pacemaker cells that sends electrical signals to the atria and ventricles so they can contract

Question 8

What are the two types of cardiac muscle cells in the myocardium?

What are the differences between these two types of cells?

Answer 8

Cardiomyocytes and pacemaker cells

Cardiomyocytes:
- Make up 99% of cardiac muscle cells

Pacemaker cells:
- Make up 1% of cardiac muscle cells
- Conduct cardiomyocytes to contract rhythmically

Question 9

Match each of the three layers of the walls of the heart (endocardium, myocardium, and pericardium) with the description that best matches it.

Answer 9

Pericardium: Protects the heart

Endocardium: Covers the heart valves

Myocardium: Responsible for the beating of the heart

Question 10

Is the blood flowing through the mitral valve oxygenated or deoxygenated? Explain your reasoning.

Answer 10

Oxygenated, because this blood travels from the left atrium, through the mitral valve, to the left ventricle

Question 11

True or False. The coronary arteries carry blood to the heart.

Answer 11

True

Question 12

True or False. Systole is when the heart is contracting, diastole is when the heart is fully relaxed

Answer 12

False

Question 13

Explain why the blood from the cardiac veins empties into the right atrium of the heart. Focus on function rather than anatomy in your answer.

Answer 13

So it can travel to the right ventricle and out to the lungs, where it can become oxygenated again.