Chapter 17-Anatomy & Physiology Flashcards
What is the primary function of the heart?
To pump blood to supply oxygen-enriched red blood cells to the tissues of the body
The heart’s pumping action is crucial for maintaining circulation and delivering oxygen to tissues.
What divides the heart into left and right sides?
The septum
The septum is a wall that separates the two sides of the heart.
What are the upper chambers of the heart called?
Atria
Each side of the heart contains one atrium.
What are the lower chambers of the heart called?
Ventricles
The ventricles pump outgoing blood from the heart.
How does blood leave each chamber of the heart?
Through a one-way valve
These valves ensure blood flows in the correct direction.
What is the main artery of the body?
The aorta
The aorta carries blood ejected from the left ventricle to the other arteries.
Where does the right side of the heart receive blood from?
From the veins of the body (oxygen-poor blood)
This includes blood from the superior and inferior venae cavae.
What happens to blood in the lungs?
It receives fresh oxygen and releases carbon dioxide
This process is part of pulmonary circulation.
What type of blood does the left side of the heart receive?
Oxygen-rich (oxygenated) blood
This blood comes from the lungs through the pulmonary veins.
Why is the left ventricle more muscular than the right ventricle?
Because it must pump blood into the aorta to supply all the other arteries
The left ventricle is responsible for systemic circulation.
What controls the heart rate?
The heart’s electrical conduction system
This system allows the atria and ventricles to work together.
Where do normal electrical impulses in the heart begin?
In the sinoatrial (SA) node
The SA node is located in the upper part of the right atrium.
What is the function of the atrioventricular (AV) node?
To slow the signal for about one- to two-tenths of a second
This delay allows blood to pass from the atria to the ventricles.
What is automaticity in cardiac muscle cells?
The ability to contract spontaneously without a stimulus from a nerve source
This characteristic is unique to cardiac muscle cells.
What regulates the impulses originating in the SA node?
Impulses from the brain via the autonomic nervous system
The autonomic nervous system controls involuntary bodily functions.
What are the two parts of the autonomic nervous system?
Sympathetic nervous system and parasympathetic nervous system
These systems work together to maintain balance in bodily functions.
What is the role of the sympathetic nervous system?
To speed up heart rate and increase respiratory rate during physical activity
It is often referred to as the fight-or-flight system.
What does the parasympathetic nervous system do?
Slows heart and respiratory rates and dilates blood vessels in the digestive system
It opposes the effects of the sympathetic nervous system.
True or False: The sympathetic nervous system takes control during times of relaxation.
False
The parasympathetic system takes control during relaxation.
