Anatomy & Physiology Flashcards
What is the primary function of the heart?
Pumps blood to supply oxygen-enriched red blood cells to the tissues of the body
What divides the heart into left and right sides?
The septum
What are the two upper chambers of the heart called?
Atria
What are the two lower chambers of the heart called?
Ventricles
What keeps the blood moving through the circulatory system in the proper direction?
One-way valves
What is the main artery of the body that receives blood from the left ventricle?
Aorta
Where does the right side of the heart receive blood from?
Veins of the body
What enters the right atrium from the body?
Blood from the superior and inferior venae cavae
What happens to blood in the pulmonary circulation?
It is reoxygenated
How does blood return to the heart after being oxygenated in the lungs?
Through the pulmonary veins
What type of blood does the left side of the heart receive?
Oxygen-rich (oxygenated) blood
Why is the left ventricle more muscular than the right ventricle?
It must pump blood into the aorta to supply all the other arteries of the body
What system controls the heart rate and coordinates the contraction of the atria and ventricles?
The electrical conduction system
What is the sinoatrial (SA) node responsible for?
Generating normal electrical impulses that control heart rate
What is the function of the atrioventricular (AV) node?
Slows the electrical signal to allow blood time to pass from the atria to the ventricles
What are the structures that spread impulses throughout the ventricles?
Bundle of His, right and left bundle branches, and Purkinje fibers
What unique characteristic do cardiac muscle cells have?
Automaticity
What does automaticity allow cardiac muscle cells to do?
Contract spontaneously without a stimulus from a nerve source
What part of the nervous system controls the heart’s impulses?
The autonomic nervous system
What are the two parts of the autonomic nervous system?
Sympathetic nervous system and parasympathetic nervous system
What is the role of the sympathetic nervous system?
Increases heart rate, respiratory rate and depth, dilates blood vessels in muscles, constricts blood vessels in the digestive system
What does the parasympathetic nervous system do?
Slows heart and respiratory rates, constricts blood vessels in muscles, dilates blood vessels in the digestive system
True or False: The sympathetic and parasympathetic nervous systems work independently of each other.
False
In times of stress, which part of the autonomic nervous system gains primary control?
Sympathetic nervous system
