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Dr. Kingsley's PE 220
Exam #4
148
Physiology
Undergraduate 1
11/02/2012

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Term
An increase in heart rate can be mediated through ________.
Definition
a decrease in parasympathetic activity and an increase in sympathetic activity
Term
The term autorhythmicity refers to the heart's ability to ________.
Definition
generate its own contractile cycle
Term
Which of the following is the correct conduction pathway through the heart?
Definition
SA node; AV node; bundle of His; bundle branches; Purkinje fibers
Term
What is the function of the sodium

-calcium exchanger in cardiac muscle?
Definition
remove calcium from the cytosol by transporting it to the extracellular fluid
Term
During phase 3 of a contractile cell action potential, ________.
Definition
only potassium permeability is increased
Term
What is occurring during ventricular ejection?
Definition
the AV valves are closed and the semilunar valves are open as blood is leaving the ventricles
Term
Opening of which of the following channels contributes to the spontaneous depolarizaton of pacemaker cells?
Definition
both calcium channels and funny channels
Term
During which phase of the cardiac cycle are all four heart valves open?
Definition
None
Term
Which of the following components of an ECG represents ventricular depolarization?
Definition
QRS complex
Term
The rapid depolarization phase of a contractile cell is phase ________.
Definition
0
Term
The end

-diastolic volume minus the end-systolic volume is the ________.
Definition
Stroke volume
Term
________ provide the pathway for the movement of electrical current between the cells of the conduction pathway and the ventricular myocytes.
Definition
Gap Junctions
Term
During isovolumetric relaxation, _____.
Definition
the AV and semilunar valves are closed and ventricular pressure is decreasing
Term
A decrease in afterload will lead to a(n) ________.
Definition
increased stroke volume
Term
What causes the rapid depolarization phase of a contractile cell action potential?
Definition
sodium movement into the cell
Term
Which side of the heart has thicker muscles, and why?
Definition
The left side, needs thicker muscles for more force to send blood to brain. Left needs more oxygen and blood flow, does more work, needs more blood.
Term
Order of blood vessels
Definition
Heart, arteries(away from heart), arterioles(branching of arteries), Capillaries(tissue level), Venules(branching of veins), Veins(carry to the heart)
Term
Arteries
Definition
Relatively large, brancing vessels that conduct blood away from the heart
Term
Arterioles
Definition
Small branching vessels with high resistance
Term
Capillaries
Definition
Site of exchange between blood and tissues
Term
Path of blood flow
Definition
Vena cavae->right atrium->tricuspid->right ventricle->pulmonary semilunar valve->pulmonary artery->lungs->pulmanary veins->left atrium->bicuspid(mitral)->left ventricle->aortic semilunar valve->aorta->systemic circuit
Term
How many parts do each of the lungs have?
Definition
Left lung has 2 parts, right lung has 3 parts
Term
What is the inflammation of the pericardium called?
Definition
Pericarditis==>membranous sac surrounding heart lubricates heart and decreases friction, it becomes inflammed causing Pericarditis
Term
What are the three layers of the heart wall?
Definition
Endocardium(inner)=>layer of endothelial cells(respond to stretch/pumps)
Myocardium(middle)cardiac muscle(muscle of the heart/respond)
Epicardium(outer)external membrane(sets structure)
Term
If actin and myosin are too far apart what will result?
Definition
If they are too far apart we can't get a good contraction and blood will start to pool in the heart. This will cause a backflow into the lungs causing us to drown in our own blood(fluids). This is called cardiomyopathy. It can cause congestive heart failure and death
Term
Properties of cardiac muscles
Definition
Intercalated disks-gap junctions(allow cells to communicate directly)--cause heart to contract as a unit
Desmosomes(does not fatigue because of this)--resists stress
Atria and ventricles--separate units
Term
Functions of cardiac muscles
Definition
Rhythmic contraction and relaxation generates heart pumping action
Contraction pushes blood out of heart into vasculature
Relaxation allows heart to fill with blood
Must work together, if not we have no blood flow
Term
AV valves
Definition
Atrioventricular valves
Right AV valve=tricuspid valve
Left AV valve=bicuspid valve=mitral valve(because it looks like the miter hat(pope hat)(mitro valve prolapse=blook backflow causing light headed)
Papillary muscles and chordae tendinae(keep AV valves from everting)
Term
Semilunar valves
Definition
Shaped like a half moon
Aortic valve
Pulmonary valve
Term
Where is the cardiovascular control center?
Definition
medulla oblongata
Term
The long
-term regulation of arterial blood pressure involves ________.
Definition
the control of blood volume by the kidneys
Term
In comparison to the systemic circuit, the pulmonary circuit ________.
Definition
has lower resistance to blood flow
Term
The ________ is bounded by the interior surface of the chest wall and the exterior surface of the lung.
Definition
interpleural space
Term
The transition from the conducting to the respiratory zone in the lungs occurs at the ________.
Definition
respiratory bronchioles
Term
The pressure gradient for blood flow through the systemic circuit is the mean arterial pressure.
Definition
True
Term
The smallest (and most distal) structures that remain a component of the conducting zone in the respiratory tract are the ________.
Definition
terminal bronchioles
Term
Due to their diameter, capillaries have the greatest individual resistance, while the arteriole networks have the greatest total resistance.
Definition
True
Term
________ are the most common cells that line the surface of the alveoli and are therefore associated with the exchange of gases within the lungs.
Definition
Type I alveolar cells
Term
Which of the following equations correctly relates flow, pressure, and resistance?
Definition
Pressure
= Flow × Resistance
Term
The upper airway refers to the passageway for air that is located within the head and neck.
Definition
True
Term
An increase in total peripheral resistance, in the absence of any change in cardiac output, would ________.
Definition
elevate mean arterial pressure
Term
Intrinsic regulation of arteriolar radius regulates mean arterial pressure.
Definition
False
Term
The conducting zone adjusts the temperature and humidity of the air entering the respiratory tract.
Definition
True
Term
The difference between intrapleural pressure and intra
-alveolar pressure is ________.
Definition
transpulmonary pressure
Term
Spread of excitation between cells
Definition
Atria contract then followed by ventricles. The coordination due to presence of gap junctions and conduction pathways. Gap junctions for electrical coupling.
Term
How many years are deducted from our lives due to lack of physical exercise?
Definition
4
Term
Conduction system of heart
Definition
1. Sinoatrial(SA)node(pacemaker) internodal pathway
2. Atrioventricular(AV)node
3. AV bundle(bundle of His)
4. Right and left bundle branches
5. Purkinje fibers
Term
Control of heart beat by pacemakers(autorhythmic cells)
Definition
Spontaneous depolarization caused by closing K+ channels and opening two types of channels: If(funny) channels(Na+ and K+, net depolarization
Calcium channels(further depolarization)

Depolarization to threshold:
Open fast calcium channels-->action potential
Repolarization:
Open K+ channels
Term
What are the 5 phases of contractile cell action potentials?
Definition
Phase0-->increased permeability to sodium
Phase1-->decreased permeability to sodium
Phase2-->increased permeability to calcium, decreased permeability to potassium
Phase3-->increased permeability to potassium, decreased permeability to calcium
Phase4-->resting membrane potential
Term
Steps of excitation-contraction coupling
Definition
1. Depolarization of cardiac contractile cell to threshold via gap junction
2. Opening of calcium channels in plasma membrane
3. Action potential travels down T tubules
4. Calcium is released from sarcoplasmic reticulum by calcium-induced calcium release
action potentials in T tubules
5. Calcium binds to troponin causing shift in tropomyosin
6. Binding sites for MYOSIN on ACTIN are exposed
7. Crossbridge cycle occurs
Term
Relaxation of cardiac muscle
Definition
Remove calcium from cytosol
Calcium ATPase in sarcoplasmic reticulum and plasma membrane
Na+-Ca2+ exchanger in plasma membrane
Troponin and tropomyosin return to position covering myosin binding sites on actin
Term
What are 2 factors that deal with cardiac output?
Definition
Sympathetic and parasympathetic nervous system
Term
If Stroke volume goes up, what does afterload do?
Definition
It goes down
Term
Starling's Law
An increase in end-diastolic volume causes stroke volume to what?
Definition
Increase
Term
Intrinsic control-Frank-Starling's law
Definition
Increase venous return-->Increase strength of contraction-->Increase stroke volume
Term
Principle of Frank-Starling's law
Definition
Increase end-diastolic volume stretches muscle fibers
Fibers closer to optimum lenght
Optimum lenght=greater strength of contraction
Result=increased stroke volume
Term
Factors affecting cardia output: stroke volume
Definition
Ventricular contractility
End-diastolic volume
Afterload
Treppe effect


These 4 factors plus parasympathetic and sympathetic affect heart rate
Term
Effects of parasympathetic activity on heart rate
Definition
Increased parasympathetic activity(vagus nerve)-->Mucarinic cholinergic receptors in SA node-->Increase open state of K+ channels and closed state of calcium channels-->decreased rate of spontaneous depolarization and hyperpolarize cell-->decrease heart rate
Term
Effects of sypathetic activity on heart rate
Definition
Increased sympathetic activity(nerves or epinephrine)-->Beta 1 receptors in SA node-->Increased open state of funny and calcium channels-->Increased rate of spontaneous depolarization-->Increase heart rate
Term
How many beats per minute before it is considered sympathetic activity?
Definition
75-100=sympathetic activity
Under 75=parasympathetic activity
Term
Heart rate-determined by SA node firing rate
Definition
SA node intrinsic firing rate=100/min
No extrinsic control on heart, hr=100
SA node under control of ANS and hormones
Rest:parasympathetic dominates, HR=75
Excitement: sympathetic takes over, HR increases
Term
Cardiac output
Definition
Volume of blood pumped by each ventricle per minute
Cadiac output= CO=SV*HR
Average CO=5 liters/min at rest


At rest: untrained=5 liters/min
With exercise training=6 liters/min
Term
Ejection fraction
Definition
Fraction of end-diastolic volume ejected during a heartbeat

Ejection fraction=stroke volume/end-diastolic volume


Normal=60-70%
Chronic heart disease could be as low as 6%
Term
Ventricular volume
Definition
EDV=end-diastolic volume(volume of blood in ventricle at the end of diastole(relaxation))
ESV=end systolic volume(volume of blood in ventricle at the end of systole(contraction))
SV=stroke volume(volume of blood ejected from ventricle each cycle)
SV=EDV-ESV(how much blood was ejected from heart during heart beat)
Term
Ventricular diastole

Isovolumetric ventricular relaxation
Definition
Ventricle muscle relaxes so that pressure is less than aorta
Aortic valve closes
Pressure in ventricle continues dropping until it is less than atrial pressure
Term
Ventricular diastole

Ventricular filling
Definition
AV valve opens
Blood moves from atria to ventricle
Passive until atrium contracts
Term
Ventricular systole

Isometric ventricular contraction
Definition
AV and aortic valves closed
Ventricular pressure increases until it exceeds atrial pressure
Term
Ventricular systole

Ventricular ejection
Definition
Aortic valve opens
Blood moves from ventricle to aorta
Term
Four phases of cardiac cycle
Definition
Phase#1: Ventricular filling-pressure atria>pressure ventricles
AV valves open
Passive phase-no atria or ventricular contraction
Active phase-atria contract
Phase#2: Isometric ventricular contraction-ventricle contracts-increases pressure
AV and semilunar valves closed
No blood entering or exiting ventricle
Phase#3: Ventricular ejection-pressure ventricles>pressure arteries
Semilunar valves open
Phase#4: Isovolumetric ventricular relaxation-ventricle relaxes-decreases pressure
AV and semilunar valves closed
No blood entering or exiting ventricle
Term
Valves open passively due to pressure gradients
Definition
AV valves open when: Pressure atria>pressure ventricles
Semilunar valves open when:
Pressure ventricles>pressure arteries
Term
Two main periods of cadiac cycle(mechanical events)
Definition
Systole(contraction or ejecting of blood) ventricle contraction
Diastole(relaxation or filling of blood) ventricle relaxation
Term
P wave
Definition
Atrial depolarization
Term
QRS Complex
Definition
Ventricular depolarization and atrial repolarization
Term
T wave
Definition
Ventricular repolarization
Term
PQ segment
Definition
AV nodal delay
Term
QT segment
Definition
Ventricular systole
Term
QT interval
Definition
ventricular diastole
Term
External respiration
Definition
Pulmonary ventilation(movement of gasses in)
Exchange between lungs and blood
Transportation in blood
Exchange between blood and body tissue
Term
Upper airways
Definition
Air passages of the head and neck: nasal cavaties, oral cavaties, pharynx
Term
Respiratory tract
Definition
Airways from pharynx to lungs
Larynx(behind pharynx)
Conducting zone(make up 4/5 of lungs)
Respiratory zone(make up 1/5 of lungs)

Conducting zone has nothing to do with gas exchange but everything to do with moving air

Respiratory zone is only at the very bottom of the lungs
Term
Structures of the conducting zone
Definition
Trachea(coated in creacoat cartilage)
Bronchi(left and right)
Second bronchi-->right side(3 lobes of right lung), left side(2 lobes of left lung)
Tertiary bronchi(20-23 orders of branching)
Bronchioles(very small, less than 1mm diameter)
Terminal bronchioles(end of conduction zone)
Term
Functions of the conducting zone
Definition
Air passageway: 150mL volume=dead space volume(no exchange of gas, that air is last in, first out...waisted air)
Increase air temperature of body temperature
Humidify air
Term
Epithelium of the conducting zone
Definition
Goblet cells(secrete mucus that grabs on to particles in the air)
Ciliated cells(cilia move particles towards mouth
Mucus escalator(cough up the mucus)
Term
Structures of the respiratory zone
Definition
Respiratory bronchioles
Alveolar ducts
Alveoli(prime place for gas exchange)
Alveolar sacs
Term
Functions of the respiratory zone
Definition
Exchange gases between air and blood
Mechanism is by diffusion(gases don't require transporter, No ATP is required, it is passive)
Term
Epithelium of the respiratory zone
Definition
Respiratory membrane-->epithelial cells of alveoli
Endothelial cells of capillary

If the membrane is thicker, it is more difficult to diffuse gases into blood
Term
Alveoli
Definition
Site of gas exchange
300 million alveoli in the lungs(tennis court size)
Rich blood supply(capillaries form sheet over alveoli)
Alveolar pores
Term
Type I alveolar cells
Definition
Make up wall of alveoli(structural cells)
Single layer epithelial cells
Term
Type II alveolar cells
Definition
Secrete surfactant(basically it is soap, only formed 5-10 days before birth)
Alveolar macrophages
Term
What are bronchitis and pneumonia caused by?
Definition
Bronchitis is caused by partial covering of mucus on the alveolar wall
Pneumonia is where the wall is covered completely with mucus
Term
Cystic fibrosis
Definition
Disease where you were born with more mucus and you are unable to clear the mucus (mucus escalator)
Term
Roles of pressure in pulmonary ventilation
Definition
Air moves in and out of lungs by bulk flow
Pressure gradient drives flow
Air moves from high to low pressure
Inspiration-pressure in lungs less than atmosphere
expiration-pressure in lungs greater than atmosphere
Term
Pulmonary pressures
Definition
Atmospheric pressure=Patm
Intra-alveolar pressure=Palv-->pressure of air in alveoli
intrapleural pressure=Pip-->pressure inside pleural sac
Transpulmonary pressure=Palv-Pip-->distending pressure across the lung wall
Term
Atmospheric pressure
Definition
760 mm Hg at sea level
Decreases as altitude increases
Increase unde water
Other lung pressures given relative to atmospheric(set Patm=0mm Hg)
Term
Intra-alveolar pressure
Definition
Pressure of air in alveoli
Given relative to atmospheric pressure
Varies with phase of respiration-->during inspiration=negative(less than atomspheric)
During expiration=positive(more than atmospheric)
Difference between Palv and Patm drives ventilation
Term
Intrapleural pressure
Definition
Pressure inside pleural sac
Always negative under normal conditions
Always less than Palv
Varies with phase of respiration
At rest, -4m Hg
Negative pressure due to elasticity in lungs and chest wall
Lungs recoil inward
Chest wall recoils outward
Opposing pulls on intrapleural space
Surface tension of intrapleural fluid hold wall and lungs together.
Surface tension is dictated by surfactin
Term
Transpulmonary pressure
Definition
Transpulmonary pressure=Palv-Pip
Distending pressure across the lung wall
Increase in transpulmonary pressure
Increase distending pressure across lungs
Lungs(alveoli)expand, increasing volume
Term
Pneumothorax
Definition
Puncture in pleural sac
Term
Flow rule
Definition
Pressure=force exerted by blood
Flow occurs from high pressure to low pressure
Flow=P/R
R=P/F
P=R*F
Resistance goes up flow goes down
Term
Flow rule
Definition
Pressure=force exerted by blood
Flow occurs from high pressure to low pressure
Flow=P/R
R=P/F
P=R*F
Resistance goes up flow goes down
Term
Pressure gradient in the cardiovascular system
Definition
High flow=high pressure
Pressure gradient drive flow from high pressure to low pressure
Flow due to pressure gradient=bulk flow
Heart creates pressure gradient for bulk flow of blood
A gradient must exist throughout circulatory system to maintain blood flow
Term
Pressures of the pulmonary and systemic circuit
Definition
Pulmonary circuit has no pressure
Systemic circuit around 75mm Hg
Term
Resistance in the cardiovascular system
Definition
Pressure gradient in systemic circuit much greater than for pulmonary circuit
Flow through both circuits equal
Flow=P/R
Resistance through pulmonary circuit much less than through systemic circuit
Term
Factors affecting resistance to flow
Definition
Radius of vessel(largest factor)
In arterioles(and small arteries) can regulate radius
Lenght of vessel(same throughout body)
Viscosity of fluid(slipage)=n
Blood viscosity dependent on amount of RBC's and proteins
Higher # of RBC's the more chance of blood clot(no slipage)
Term
Poiseuille's law
Definition
R=8nL/R(to the 4th power)
Flow=P/R=Pr(to the 4th power)/8nL
Lenght goes up, flow goes down
Any change in radius of vessel changes resistance by 4 times
Term
The effect of arteriole radius on blood flow
Definition
Regulation of radius of arterioles(and small arteries)
Vasoconstriction(sympathetic mediated, epi, norepi)
Decrease radius->increase resistance
Vasodilation(parasympathetic)
Increase radius->decrease resistance
Pulmonary circuit less resistance than systemic
Lower pressure gradient required for blood flow
Term
Total peripheral resistance
Definition
Combined resistance of all blood vessels within the systemic circuit
Resistance across a network of blood vessels depends on resistance of all vessels
Flow through network varies with resistance
Vasoconstriction in network->increase resistance->decrease flow
Vasodilation in network->decrease resistance->increase flow
If we vasoconstrict organs we can flood muscles with blood(exercise) and vice versa
Term
Relating pressure gradients and resistance in the systemic circulation
Definition
Flow=P/R
Flow=Cardiac output(CO)
P=Mean arterial pressure(MAP)
R=Total peripheral resistance(TPR)
CO=MAP/TPR
CO=HR*SV
Term
Determinants of Mean Arterial Pressure
Definition
Determined by:
Heart rate
Stroke volume
Total peripheral resistance
MAP=CO*TPR
CO=HR*SV
Therefore: MAP=HR*SV*TPR
Term
Extrinsic control of arteriole radius
Definition
MAP regulated through control of heart(CO) and arterioles and veins(TPR)
Neural control
Hormonal control
Term
What are the 6 ways to change heart rate
Definition
Afterload, preload, treppe, contractility, sympathetic, parasympathetic
Term
Mean arterial pressure(MAP)
Definition
MAP=driving force of blood flow
F=P/R
Regulating MAP critical to normal function
MAPhypotension(stand up too quickly and get dizzy)
Inadequate blood flow to tissues
MAP>normal
Hypertension
Stressor for heart and blood vessels

Faiting due to hypotension is good because you fall to the ground and with no gravity to fight with you can get blood back to the brain.
Cardiogenic shock is when your heart beats so fast to try to get the blood to brain that your heart explodes in your chest
Term
Short-term regulation of MAP
Definition
Seconds to minutes
Regulate cardiac output and total peripheral resistance
Involve heart and blood vessels
Primary neural control
Term
Long-term regulation of MAP
Definition
Minutes to days
Regulate blood volume
Involve kidneys
Primary hormonal control
Term
Cardiovascular control center
Definition
Medulla oblongata
Integration center for blood pressure regulation
Input
Arterial baroreceptors(found in aorta and carotid arteries)
Low pressure baroreceptors(found in right atrea)
Chemoreceptors
Proprioceptors(where body is located in space)
Higher brain centers
Outputs
Sympathetic
Parasympathetic
Term
Autonomic output to cardiovascular effectors
Definition
Parasympathetic input to
-SA node(decrease HR)
-AV node
Sympathetic input to
-SA node(increase HR)
-AV node
-Ventricular myocardium(increase contractility)
-Arterioles(increase resistance)
-Veins(increase venomotor tone)
Term
Mechanics of breathing
Definition
Movement of air in and out of lungs due to pressure gradient.
Mechanics of breathing describes mechanisms for creating pressure gradient
Pressure dictates volume
Term
Forces of air flow
Definition
Boyle's Law: pressure is inversely related to volume
Pressure goes up, volume goes down
Thus, can change alveolar pressure by changing its volume
R=resistance
Resistance related to radius of airways and mucus
Term
Determinants of intra-alveolar pressure
Definition
Factors determining intra-alveolar pressure
Quantity of air in alveoli
Volume of alveoli
Lungs expand-alveolar volume increases-->Palv decreases
Pressure gradient drives air into lungs
Lungs recoil-alveolar volume decreases->Palv increases
Pressure gradient drives air out of lungs
Term
Muscles of respiration
Definition
Inspiratory muscles increase volume of thoracic cavity
Diaphram, external intercostals
Expiratory muscles decrease volume of thoracic cavity
Internal intercostals, abdominal muscles
Term
Pleural pressure is always positive or negative?
Definition
Negative
Term
Pressure gradient for ventilation
Definition
Patm-Patv
Term
Transpulmonary pressure
Definition
Patv-Pip
Term
Factors affecting lung compliance
Definition
Elasticity-->more elastic-->less compliant
Surface tension of lungs-->greater tension-->less compliant

Emphysema is when you lungs are not elastic. You have to work your muscles for each breath.
Term
Surface tension in lungs
Definition
Thin layer fluid lines alveoli
Surface tension due to attractions between water molecules
Surface tension=force for alveoli to collapse or resist expansion
Term
To overcome surface tension
Definition
Surfactant secreted by type II alveoli cells
Surfactant=detergent that decreases surface tension
Surfactant increases lung compliance
Makes inspiration easier
Term
Airway resistance
Definition
As airways get smaller in diameter they increase in number, keeping overall resistance low
Pressure gradient needed for air flow thus low-->~1mm Hg
An increase in resistance makes it harder to breath
Pressure gradient needed for air flow >1mm Hg
Term
When climbing a mountain, is there less oxygen with elevation?
Definition
No, the air is composed of the same percentage of oxygen as at sea level. The difference is the pressure. As elevation increases, pressure decreases making it harder for you to breath.
Mt. Everest climbers lost about 10% in their IQ due to an extended period of time without oxygen.
18,000 feet is what they call "dead zone" where pressure is very little and very hard to breath which can lead to hypoxic or lack of oxygen
Term
Extrinsic control of bronchiole radius
Definition
Autonomic nervous system-->sympathetic
Relaxation of smooth muscle
Bronchodilation
Parasympathetic
Contraction of smooth muscle
Bronchoconstriction
Hormonal control-epinephrine
Relaxation of smooth muscle
Bronchodialation
Term
Intrinsic control of bronchiole radius
Definition
Histamine(causes more secretion)bronchoconstriction
Released during asthma and allergies
Also includes mucus secretion
Carbon dioxide-bronchodilation
Term
Gas composition of air
Definition
79% Nitrogen
21% Oxygen
Trace amounts of carbon dioxide, helium, argon, etc.
Water can be a factor depending on humidity
Term
Solubility of gases in liquids
Definition
Gas molecules can exist in gas form or dissolve in liquid
Ability to dissolve depends on properties of gas and properties of liquid
Both vaporized and dissolved gases exert partial pressures
The partial pressure of a gas affects the amount of gas that goes into solution
Partial pressure of vaporized and dissolved gases will be equal at equilibrium
Term
Exchange of oxygen and carbon dioxide
Definition
Gas exchange in the lungs
Gas exchange in respiring tissue
Determinants of alveolar Po2 and Pco2
Term
Diffusion of gases
Definition
Gases diffuse down pressure gradients->high to low pressure
In gas mixtures, gases diffuse down pressure gradients->high partial pressure to low partial pressure
A particular gas diffuses down its own partial pressure gradient
Pressure of other gases irrelevant
Term
Rate of diffusion in lungs
Definition
Diffusion between alveoli and blood is rapid
Small diffusion barrier
Large surface area
Term
Hyperpnea
Definition
Increased ventilation due to increased demand
Minimal changes to arterial Po2 and Pco2
Term
Hypoventilation
Definition
Ventilation does not meet demands
Arterial Po2 decreases
Arterial Pco2 increases
Term
Hyperventilation
Definition
Ventilation exceeds demands
Arterial Po2 increases
Arterial Pco2 decreases
Term
Dyspnea
Definition
Labored or difficult breathing
Term
Apnea
Definition
Temporary ceasation of breathing
Term
Oxygen transport in blood
Definition
1. Oxygen transport by hemoglobin
2. The hemoglobin-oxygen dissociation curve
3. Other factors affecting affinity of hemoglobin for O2

Oxygen not very soluble in plasma
Thus only 3.0mL/200mL arterial blood oxygen dissolved in plasma(1.5%)
Other 197mL arterial blood oxygen transported by hemoglobin
Term
Oxygen binding to hemoglobin
Definition
Hb+O2<-->Hb*O2
Hb=deoxyhemoglobin
Hb*O2=oxyhemoglobin
Term
Saturation of hemoglobin
Definition
Hemoglobin can bind up to 4 oxygen molecules
Binding of oxygen to hemoglobin follows law of mass action
More oxygen->more binds to hemoglobin
Non-linear relationship
Positive cooperativity

Sickle cells may only carry 1 or 2 oxygens
Term
Saturation of hemoglobin
Definition
A measure of how much oxygen is bound to hemoglobin
100% saturation-->all 4 binding sites on hemoglobin have oxygen bound to them
Term
Oxygen-carrying capacity of blood
Definition
When 100% saturated, 1 gram hemoglobin carries 1.34mL oxygen
Normal blood hemoglobin levels=12-17gm/dL
Oxygen-carrying capacity of hemoglobin in blood=200mL oxygen per liter blood
Term
Effects of O2 affinity changes
Definition
Shift right-->less loading of O2 and less unloading
Shift left-->more loading of O2 and less unloading
Term
Temperature effects:O2 saturation
Definition
Higher temperature:active tissues, shift right, more O2 unloading in tissues, more O2 delivered to tissues
Term
pH effects: O2 saturation
Definition
Bohr effect:Lower pH increases O2 unloading
Active tissues->produce more acid pH decreases in tissues
Decreased pH causes shift right in saturation curve
More O2 is unloaded to tissues
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