Review from Tuesday February 1st
What is the main function of the Cardiovascular system discussed in class?
Transport and exchange of gases + nutrients + waste
How do arteries and veins appear histologically
Arteries: big circular vessels
Veins: Uneven vessels like look like a worm :)
What is the CO of someone who has a SV of 50 mL/beat and a Heart Rate of 70 BPM?
50 x 70 = 3500 mL/min / 1000 mL
3.5 L/min
Fast neural mechanism has a time frame of ____ while slow hormonal mechanisms have a time frame of ____.
Seconds; hours to days
The two routes of simple squamous epithelium is _____ and _____
Transcellular and Paracellular
The valve that separates the Atrium from the ventricle are _____.
Atrioventricular valves
What is the Mean Arterial Pressure Equation
DBP + (SBP-DBP)/3
What are the positive and negative chronotropic and inotropic factors?
+ Chronotropic: Increase SNS input; increase Catecholamines
- Chronotropic: Decrease SNS input; Increased PNS
+ Inotropic: Increased contractility; increased SNS input to the myocardium
- Inotropic: Decrease contractility; decreased SNS input to the myocardium
When CO = VR this is called a ____
Steady state point
For capillary exchange, the hydrostatic pressure located in the _______ is greater than the hydrostatic pressure in the _______.
Arteries; veins
What is the difference between systemic and pulmonary circuits
Systemic circuit: Carry oxygenated blood away from heart
- Circulate blood from heart to rest of body
Pulmonary circuit: carry deoxygenated blood to the heart
- Circulate blood from heart to lungs
R = 8ny/Pir^4
As resistance increases --> flow decreases
Capacitance: stiff walls --> decrease flow
What are the factors that increase venous return?
Skeletal muscle pumps
Respiratory pumps
Increase in total lung volume
Increase in venoconstriction
Decrease in TPR
Increase Cardiac Output
Explain the Cardiac function curve
Right arterial pressure is proportional to EDV.
RAP increases due to more sarcomeres stretching
When RAP increase, this causes cardiac output to increase.
When RAP decreases, this cause Venous return to increase.
Venous return is increased by central venous pressure.
What is the Starling equation
List each blood vessel layer from most internal to external. Also list what layer is made of.
Tunica intima - endothelial cells and connective tissue (collagen)
Tunica Media - smooth muscle and elastic tissue
Tunica Externa - Elastic tissue and loose CT
How does Sympathetic Innervation, Catecholamines, and Local Control affect vasodilation and vasoconstriction?
Sympathetic Innervation:
- Muscle tone of vessels --> Vasodialate with increase SNS input
Limb Arteries also vasodialate with increase SNS input
Other arteries (eg. digestive tract): Vasoconstrict
Catecholamines: Increase with increases SNS input --> vasoconstriction
Local Control: When BP rises it vasocontricts; vice versa when BP is low
What are the steps of the conduction system?
1. SA node receives input from SNS
2. Signal travels to AV node where is delays the signal to slow conduction speed
3. Signal travels to the AV bundle where it cannot pass excitation
4. Signal then travels to AV bundle branches
5. Signal finally travels to Purkinje fibers where is spreads signal to ventricles
Explain the fast neural mechanisms when blood pressure is low
The Baroreceptors on the carotid artery sense a low stretch --> sends input to vasomotor center --> vasomotor center increases SNS input --> SNS input is sent to the SA node and the myocardium --> this increases contractility --> increases Heart rate and blood pressure
List the steps of hemostasis
1. Collagen Exposed
2. Vascular spasm occurs
3. Formation of the platelet plug
4. Stable fibrin clot is formed
List the working tissue the Aorta brings blood to
Cerebral
Coronary
Kidneys
Splanchnic Region
Skeletal muscles
Skin
Explain how the following vessels relate to: (Hint: these are the graphs)
Vessel diameter
Cross-Sectional area
Blood Pressure
Velocity
Vessel diameter: Biggest to smallest
Arteries: Aorta --> Elastic arteries --> arterioles --> capillaries
Veins: Venae Cavae --> Veins --> Venules --> Capillaries
Cross sectional area: Capillaries have the biggest cross sectional area. Think of it as the inverse of vessel diameter.
Arteries: Capillaries --> Arterioles --> Elastic Arteries --> Aorta
Veins: Capillaries --> venules --> veins --> Vanae Cavae
Blood Pressure: Highest to lowest
Aorta --> elastic arteries --> arterioles --> capillaries --> venules, veins, venae cavae
Velocity: Highest to lowest
Arteries: Aorta --> Elastic arteries --> arterioles --> capillaries
Veins: Venae Cavae --> Veins --> Venules --> Capillaries
What are the steps of the cardiac cycle?
A. Atrial kick/systole
B. Isovolumetric contraction
C. Fast Ventricular Ejection
D. Slow Ventricular Ejection
E. Isovolumetric relaxation
F. Fast Ventricular Filling
G. Slow Ventricular filling (diastasis)
Explain the slow hormonal mechanism when blood pressure is low
The Kidneys sense a decreases of blood pressure --> Angiotensinogen (located in the liver) is converted to Angiotensin 1 due to an increase release of Renin from the Kidneys --> Angiotensin 1 is converted to Angiotensin 2 by ACE 2 (located on the lungs) --> Angiotensin 2 increases Aldosterone, Na Exchange, Thirst, and Vasoconstriction which increases BP.
In the starling equation, filtration is favored when the number is ______. Reabsorption is favored when the number is _____. Can these values change?
Positive; negative
Yes these values can change due to different concentrations and pressure changes. Many diseases can cause filtration to be favored rather than reabsorption and vice versa.