Ch. 19 Cardiovascular System Flashcards
What do Sympathetics prepare the body for?
“Fight or Flight” situations
Pacemaker Potential
The ability to reach threshold without stimulation
Afterload
The pressure that the heart must work against to pump blood into the systemic circulation
Parasymatheics
Decrease heart rate
Sympathetics
Increase heart rate
End-Diastolic Volume
The amount of blood in the ventricles immediately prior to the initiation of contraction
The Fibrous Skeleton of the heart serves to
- Isolate the atria from the ventricles
- Stabilize the heart valves
- Provide an attachment site for cardiac muscle
Pumps and channels are associated with cardiac node cells
- Slow voltage-gated Na+ channels
- Na+ leak channels
- Fast Voltage- gated Ca 2+channels
- Na+/K+ ATPase
The ____ surface of the heart, formed primarily by the left side, is called ____
posterosuperior/base
The inferior, concical end of the heart is called ____
Apex
The inferior, concical end of the heart is called ____
Apex
Norepinephrine increases heart rate by
- Increasing Ca+2 flux into the node cells
- binding to the Beta1 receptors
Cardiac node cells contain leak channels for ___ and __
Na+ and K+
End Diastolic Volume
The amount of blood in the ventricles immediately prior to initiation of contraction
