Chapter 1 Overview Flashcards
The fluid immediately outside of individual cells.
Interstitial fluid.
True or false? The interstitial fluid can be considered a large reservoir for nutrients or a large sink for metabolic products.
False. Its volume is less than half that of the cells that it serves.
The process by which solutes exchange between plasma and interstitial fluid.
Diffusion
substances are transported between organs by the process
Convection.
What are the three conditions essential for the circulatory mechanism to effectively control the composition of the interstitial fluid?
- Adequate blood flow to the Tissue capillaries.
- Incoming arterial blood Chemical composition must be optimal.
- Diffusion distances between plasma and tissue cells must be short
The pulmonary circulation is composed of.
The right heart pump and the lungs.
The systemic circulation is composed of.
The left heart pump which Supplies blood to the systemic organs.
What is the arrangement of the pulmonary and systemic circulations?
Arranged in series.
What is the arrangement of most systemic organs? What are two consequences of this system?
Arranged in parallel.
Nearly all systemic organs receive blood of identical composition.
The flow through any one of the systemic organs can be controlled. Independently of the flow through the other organs.
Which 3 organs receive blood flow just enough to supply the metabolic needs of the tissue.
The brain, the heart muscle and skeletal muscles.
The Myocardium Consumes what percentage of the oxygen supplied to it?
75%.
What percent of blood does the cardiac muscle require?
3%
What supplies the driving force for flow through a vessel?
Pressure differences.
Term for How difficult it is to make fluid flow through a tube.
vascular resistance.
What are the only two ways in which blood flow through any organ can change? Which is more likely?
By changing the pressure differences across its vascular bed.
By changing its vascular resistance*
How do you calculate flow?
Delta P/ Resistance (R)
For any given pressure difference, ______ has a very large influence on flow through a tube.
Tube radius.
Which of the following factors has the biggest influence on vascular resistance? Why?
Vessel length.
Blood viscosity.
Radii of vessels
Radii of vessels*
It can be Easily manipulated for the purpose of moment to moment control of blood
Describe convective transport.
The simple process of being swept along with the flow of the blood in which substances are contained.
the rate at which a substance is transported by connective transport depends on? (2)
Concentration of the substance in the blood and the blood flow rate
thin fibrous sac surrounding the heart
Pericardium.
Why is venous blood deficient in oxygen?
It has just passed through systemic organs that all extract oxygen from blood for their metabolism.
Which valve is between the right atrium and right ventricle?
Tricuspid valve.
Valve proceeding the lungs
Pulmonic valve.
Valve between the left atrium and left ventricle.
Mitral valve.
Name an example of an inlet valve.
Tricuspid valve.
Name an example of an outlet valve.
aortic valve
The phase of the cardiac cycle during which the ventricular muscles contract.
Systole
What prevents the AV valve from opening despite the large pressure difference between the ventricle and atrium?
Chordae tendineae
during _____ the pressure in the ventricle falls below that in the atrium
diastole
The _______ is closed during diastole arterial pressure is _____ than intra ventricular pressure
Outlet
Greater
How do you calculate cardiac output?
Cardiac output equals stroke volume times heart rate.
How do you calculate stroke volume?
Stroke volume equals end diastolic volume minus end systolic volume.
The __________ nervous system releases __________ that interacts with beta one adrenergic receptors on cardiac muscle cells to _________ the heart rate, Action potential velocity, and force of contraction.
Sympathetic
Norepinephrine
Increase
Cholinergic parasympathetic nerve fibers traveled to the heart via the vagus nerve to innervate the? (3)
SA node. AV Node, Atrial muscle.
Parasympathetic nerves release _________ and the sympathetic nerves release ___________.
acetylcholine
norephinephrine
Describe Starling’s Law.
If cardiac filling increases during diastole, the volume ejected during systole also increases.
What are the five basic requirements for effective operation of the heart?
Contractions of the cardiac muscle cells must be regular.
The valves must be fully open.
The valves must not leak.
The muscle contractions must be forceful.
The ventricles must fill adequately during diastole.
True or false? the entire circulatory system is lined with a single layer of endothelial cells
True
arteries are thick walled vessels that contain smooth muscle in addition to (2)
Elastin and collagen
Why are arteries often referred to as conduit vessels?
They have relatively low and unchanging resistance to flow.
What is the difference between arterioles and arteries?
Arterioles are smaller, Have much thicker walls, with more smooth muscle and are less elastic
Why are arterioles referred to as resistance vessels?
Because of their high and changeable resistance, which regulates peripheral blood flow through individual organs.
What are the smallest vessels in the vasculature?
Capillaries.
Why are capillaries viewed as the exchange vessels?
Due to the trans capillary diffusion of solutes that occur across these vessel walls.
Peripheral venules and veins normally contain more than what percent of the total blood volume?
50%
what happens when arteriolar diameter decreases?
Vascular resistance increases And blood flow decreases.
What effect does increased sympathetic nerve activity Have on the venous system? Why?
Venous volume decreases To increase cardiac filling and therefore cardiac output.
Why is there an energy lost from distributing the blood throughout the body?
Because blood is viscous and energy is lost to heat via fluid friction.
what is the portion of blood volume occupied by cells known as? what fraction is it?
Hematocrit
40%
Explain why an increased hematocrit level Requires more work from the heart.
The viscosity of blood increases dramatically with increases in its hematocrit. The higher the blood viscosity, the more work the heart must do to produce any given flow through the vasculature.
the liquid component of blood is known as _________ and is a complex solution of ______ and _________
plasma
electrolytes
proteins
What is serum? what is its composition identical to?
The fluid obtained from a blood sample after it has been allowed to clot
Plasma minus the clotting factors
What are the most concentrated solutes in plasma?
Inorganic electrolytes. More specifically, sodium and chloride are the most abundant.
Plasma proteins can be classified as? Which is most abundant?
Albumins*, globulins, and fibrinogen.
