Graded A+
What is the primary function of the cardiovascular system?
To deliver blood to all organs and tissues of the body, provide nutrients and
oxygen, remove wastes, deliver hormones, and transport immune system cells.
What are the two main circuits of the cardiovascular system?
Pulmonary Circuit and Systemic Circuit.
What are the layers of the heart?
Endocardium, Myocardium, and Pericardium (Visceral and Parietal).
What type of muscle is cardiac muscle?
Striated, involuntary muscle found only in the heart.
What are cardiac myocytes?
The cells that make up cardiac muscle, characterized by being short, irregularly
shaped, and branched with a central nucleus.
What is the role of intercalated discs in cardiac muscle?
They allow for electrical coupling between cardiac myocytes, enabling the heart
to function as a 'functional syncytium'.
What is diastole?
The phase of the heartbeat when the heart muscle is relaxed.
What is systole?
The phase of the heartbeat when the heart muscle contracts.
What initiates the electrical signal for the heart's contraction?
The sinoatrial (S-A) node, which fires the action potential first.
What is autorhythmicity?
The ability of the heart to generate its own rhythm without external stimuli.