Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
37 Cards in this Set
- Front
- Back
The primary role of the cardiovascular system is to maintain ______ in the _______ fluid
|
homeostasis
interstitial |
|
The physical law that governs cardiovascular operation is that flow through any segment is equal to ________ difference across that segment divided by ________
|
pressure
resistance to flow Q = deltaP/R |
|
The heart pumps blood by rhythmically filling and ejecting blood from the ventricular chambers that are served by passive/active, one-way inlet and outlet valves
|
passive
|
|
Cardiac output is effected by changes in _____ ____ and ____ ______
Changes in these can be accomplished by alteration in ________ filling and by alterations in _______ _____ activity to the heart |
heart rate
stroke volume ventricular autonomic nerve |
|
Blood flow through individual organs is regulated by changes in the diameter of their _______
|
arterioles
|
|
Changes in arteriolar diameter can be accomplished by alteration in _____ _____ activity and by variations in local conditions
|
sympathetic nerve (ONLY SYMPATHETIC)
|
|
Blood is a complex suspension of blood cells in _____ that is ideally suited to carry gases, salts, nutrients adn waste molecules through the system
|
plasma
|
|
Total body water accounts for about ____ of body weight. It is distributed amongst what three compartments?
|
60%
intracellular, interstitial, and plasma |
|
About __ L of our body water is intracellular and communicates with interstitium.
Interstitial water is about __ L Plasma accounts for __ L of water |
30L intracellular
12L interstitially 3L circulating in plasma |
|
Two conditions are essential for control of interstitial fluid composition:
1) There must be adequate ____ ___ through the tissue capillaries 2) The ______ ________ of the arterial blood must be controlled to be optimal in the interstitial fluid |
blood flow
chemical composition |
|
______ is a rapid process that can move huge quantities of material a short distance (what's an example of this in the body?)
______ is when substances move along with blood flow because they are dissolved or contained and are carried between organs (example of this?) |
Diffusion - capillaries
Convection - arteries |
|
______ circulation is the right heart pump and the lungs
______ circulation is the left heart pump supplying to the systemic organs These circulations are arranged in _____ |
Pulmonary
Systemic series - they must each pump an identical volume of blood each minute (CO) |
|
Normal cardiac output is __L/min
|
5-6
|
|
The systemic organs are functionally arranged in _____ so...
Nearly all systemic organs receive blood of identical ______ The flow through one organ can be controlled ________ of the flow through other organs |
parallel
composition (arterial blood that has just left the lungs) independently (exercise increases to some, decreases others, unchanged others) |
|
Which three organs do not recondition blood for the benefit of others, but use it solely for metabolic purposes?
|
Brain, heart muscle, skeletal muscle
|
|
Resistance is affected by several factors.
These INCREASE resistance: _____ radius _____ tube length _____ fluid viscosity Which one is most influential? |
small
long high radius - raised to the fourth power. Also the most regulated in vessels. |
|
The average pressure in systemic arteries is near ___ mmHg and in systemic veins is near ___ mmHg
|
100
0 |
|
Cardiac Output = ____ ____ x _____ _____
|
heart rate
stroke volume |
|
Effective ventricular pumping requires:
1) contractions of cells must occur at regular intervals and be ______ not _______ 2) Valves must open fully, not ______ 3) Valves must not leak, not _____ 4) muscle contractions must be _____ not failing 5) Ventricles must fill adquately during _____ |
synchronized not arrhythmic
stenotic insufficient or regurgitant forceful diastole |
|
Starlings Law: ____ ____ increases as cardiac ___-_____ volume increases
|
stroke volume
end-diastolic |
|
______ sympathetic nerves release _______ on cardiac cells which interacts with _-_____ receptors.
|
Adrenergic
Norepinephrine beta-adrenergic |
|
NE on beta-adrenergic receptors results in what 4 effects?
|
Increased HR
Increased AP conduction velocity Increase force of contraction increased rates of contraction and relaxation |
|
______ parasympathetic fibers travel via the ____ nerve to innervate what 3 structures?
|
Cholinergic
vagus SA node, AV node, and atrial muscle |
|
Cholinergic parasympathetic nerves release _____ on cardiac cells which interacts with _____ receptors. This results in what 2 effects?
|
Acetylcholine
muscarinic decrease heart rate (SA node) decrease action potential conduction velocity (AV node) May also decrease atrial contraction |
|
Control of resistance vessels (which are these?) is purely ______ acting on ALPHA receptors
|
Arterioles
sympathetic alpha |
|
Which are the resistance vessels?
Which are the exchange vessels? Which are the conduit vessels? Which are the capacitance vessels? |
arterioles
capillaries arteries veins |
|
Blood flow through vascular beds is profoundly influenced by changes in activity of sympathetic nerves innervating ______. These nerves release _______ which interacts with _-_______ receptors on smooth muscle cells to cause contraction
|
arterioles
norepinephrine alpha-adrenergic |
|
_____ and ____ are innervated by sympathetic nerves and ____ when they are activated resulting in decreased venous volume. This increases cardiac filling and therefore cardiac _____ according to Starling's
|
Venules
veins constrict output |
|
hematocrit = cell _____/total blood _____
|
volume
volume |
|
______ is an oncotic protein – provides osmotic pressure that stays in the vascular space. It can’t exchange at the capillaries so it stays there. Modulates fluid flow across vascular space.
|
albumin
|
|
Which organ in the body always receives the most blood flow?
|
Lungs
|
|
Whenever skeletal muscle blood flow increases, blood flow to the other organs must decrease.
True or False? |
False - flow depends on pressure and resistance. As long as it is constant alterations in flow through an individual bed will have no influence on those that are parallel
|
|
Would you expect a leaky aortic valve to cause a systolic or diastolic murmur?
|
Diastolic
|
|
Slowing of action potential conduction through the AV node will slow heart rate.
True or false? |
False - heart rate is regulated by action potentials in the SA node
It will only increase time between atrial and ventricular excitement |
|
What direct cardiovascular effects would you expect from an intravenous injection of a drug that stimulates a-adrenergic receptors but not beta-adrenergic receptors?
|
no direct effects on the heart (these are beta), but effects on arterioles and veins
|
|
What is the formula for resistance?
Keep in mind this is flipped in the flow equation Q= deltaP/R |
R = 8Ln/3.14r^4
L is tube length n is liquid viscosity r is radius of the tube |
|
Describe cardiac tamponade and hemorrhage and their effect on cardiac output.
|
Liquid in the pericardial sac (due to infection typically). The pressure leaves less room for cardiac filling so cardiac output is reduced (ventricles aren't filling completely)
In hemorrhage the ventricles aren't filling completely due to blood loss |