Circulatory and Immune Systems Question
View this question.
Add this question to a group or test by clicking the appropriate button below.
Which statement about the heart is correct?
- The heart contains four valves that make sure blood flows in the proper direction.
- The lower chambers of the heart are called the atria.
- The walls of the heart are made up of skeletal muscles.
- The upper chambers of the heart are called the ventricles.