Ch 11d: Cardiovascular System: Heart Flashcards
What factors can affect regulation of blood vessels?
Neural control
Renal control
What operates via reflex arcs that involve:
Cardiovascular center of medulla
Baroreceptors
Neural Control
What are baroreceptors?
Stretch receptors
Where are baroreceptors found?
In carotid synesis and aortic arch
For Neural Control:
In parasympathetic, what decreases rate and what increases delay?
SA node decreases rate
AV node increases delay
For Neural Control:
In Sympathetic, what increases rate and what decreases delay?
What else increases?
SA node increases rate
AV node decreases delay
Stroke volume increases
Study the baroreflexes for Neural Control
What is this:
- Baroreceptors quickly adapt to chronic high or low BP
- Long term control BP via kidneys
- Kidneys regulate arterial blood pressure indrectly
Renal Regulation
What is RAAS
Renin-Angiotensin-Aldosterone System
low blood flow in kidneys turns into renin which turns into Angiotensin II which stimulates what 4 things?
Stimulates release of Anti-diaretic hormone (ADH)
Stimulates Aldosterin
Vasoconstriction
Stimulates thirst center
Angiotensin II –> stimulates release of ___________ –> increase water reabsorption –> increase volume –> increase Pressure
Anti-diaretic hormone
Angiotensin II –> stimulates __________ –> causes kidneys to reabsorb salt –> reabsorb water –> increase blood volume –> Pressure
Aldosterin
Angiotensin II –> ___________ –> increase TPR –> increase Pressure
vasoconstrictor
Angiotensin II –> stimulates _________ –> water intake –> increase blood volume –> increase BP
Thirst Center
What is Hydrostatic pressure?
Blood pressure forces fluid and solutes out of capillaries
What is Osmotic pressure?
Draws fluid into capillaries
At arterial end of capillary, blood pressure’s ____________ osmotic pressure
More than
At venule end of capillary, blood pressure’s ________ osmotic pressure
less than
What happens in the 1st phase of blood flow?
Atrial diastole (ventricular filling)
What valve is open and what valve is closed during the Atrial Diastole?
AV valve: Open
SL valve: Closed
What happens in the 2nd phase of blood flow?
Atrial Systole
What valve is open and what valve is closed during Atrial Systole?
AV valve: Open
SL valve: Closed
What happens in the 3rd phase of blood flow?
Isovolumetric contraction
Are the valves opened or closed during the Isovolumetric contraction?
Closed
What happens in the 4th phase of blood flow?
Ventricular Systole (ejection phase)
What valve is open and what valve is closed during the Ventricular Systole?
AV valve: Closed
SL valve: Open
What happens in the 5th phase of blood flow?
Isovolumetric Relaxation
Are the valves open or closed during the Isovolumetric relaxation?
Closed
