Lecture 1 (Revised) Flashcards
Most Blood Volume is in?
Veins
Blood Velocity is Lowest in?
Capillaries
Capillary Beds Constitute Highest?
Surface Area
Circulatory System?
(Cardiovascular System)
A network composed of the Heart as a centralized pump, blood vessels that distribute blood throughout the body, and the blood itself
Arteries are?
Away from the Heart
Veins are?
Toward the Heart
Circulatory Functions?
1) Transport essential substances to tissues (a lot of oxygen)
2) Remove metabolic waste products (remove CO2)
3) Homeostasis
Blood Flow?
IVC + SVC –> RA –> RV –> PA –> Lungs (oxygenated) –> PV –> LA –> LV –> Aorta
Systole?
When Heart contracts to pump blood out
Diastole?
When Heart relaxes after contraction and is filled with returning blood
Arterioles?
-Regulate Blood Pressure and Blood Flow
-Largest drop in pressure
Smaller arteries have a lot more?
Smooth Muscle
Aorta’s job is?
Distribution, uses elastic tissue to pump it far
82% of all Blood?
Systemic Circulation
64% of all Blood?
Blood Reservoir
When blood gets to Arterioles it?
Decreases a lot
When blood gets to capillaries and veins?
It doesn’t have a pulse anymore
Mean Blood Pressure is similar throughout?
Aorta and Large Arteries
Cross-Sectional Area is inversely proportional to?
Velocity
Resistance is determined by?
Tube radius and length and fluid viscosity
Decrease radius of Arterioles?
Increase resistance
Pressure downstream is?
Lower than Pressure upstream
If Pressure is increased?
Flow is increased
Capillaries basically work as?
Resistors
Laminar Flow?
-Linear
-Energy efficient
Turbulent Flow?
-Irregular, turbulent flow
-More energy required
-Harmful to vessel wall
Hematocrit (Blood Composition)?
(45%) Portion of Blood that contains Red Blood Cells
By lowering Hematocrit?
Lower resistance to flow and it flows faster
2 Loops of Circulatory System?
1) Shorter (O2/CO2 exchange)
2) Longer (Distribution of Blood throughout body)
Increase in CO2, Decrease in O2?
Pulmonary Arteries
Increase in O2, Decrease in CO2?
Pulmonary Veins
Diastole and Systole you can think as one?
Heart Beat
Respiratory (Blood Function)?
-Transport O2 from lungs to tissues
-Transport CO2 from tissues to lungs
Nutrition (Blood Function)?
Transport “food” from gut to tissues (cells)
Excretory (Blood Function)?
Transport waste from tissues to kidney and skin (urea, uric acid, water)
Regulatory (Blood Functions)?
-Water content of tissues
-Water exchanged through vessel walls to tissue
Body Temperature Protective (Blood Functions)?
Antibodies, antitoxins, WBCs
Coagulation (Blood Functions)?
Blood Coagulation (Ex. fibrinogen)
Albumins (Blood Protein)?
(57%)Maintain hydrostatic
Globulins (Blood Protein)?
(38%) Immune System
Fibrinogen (Blood Protein)?
(4%) Blood Coagulation
Blood Reserve allows?
Control of blood volume and makes up for fact that capillaries are not always open
Pulse is ___ - ____?
Systole - Diastole
If you increase velocity and increases cross-sectional area?
There is more time for exchange
If you increase velocity and increases cross-sectional area?
There is more time for exchange
Don’t want blood to move to fast because?
Need time to exchange processes
Don’t want blood to move to fast because?
Need time to exchange processes
If you decrease a tube radius, increase?
Resistance a lot
Blood flow is controlled primarily by?
Regulating vessel radius
Parallel?
-2 paths they can choose
-Add more capillaries (work as resistors) (not much change)
-Greatly reduces resistance to blood flow (more parallel circuits, less total resistance)
Series?
-No change in path, they just go straight through
-Add them up
-BP decreases downstream
When a given area of vasculature is contracted?
Upstream pressures are increased and downstream pressures are decreased, as well as blood flow is decreased
When there are a lot of Parallel Vessels, changing the resistance of a small number of these vessels will have?
A minimal effect of Total Resistance
Blood viscosity changes depending on?
Tubing dimensions and hematocrit
Flow and Viscosity are?
Inversely related
If you decrease viscosity?
Increase flow (lower resistance to flow)
If you decrease hematocrit?
Increase flow (can flow faster and in center of vessel)
