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;
91 Cards in this Set
- Front
- Back
What are the functions of the cardiovascular system
|
*transports: waste, CO2, 02 etc.
*Regulates: body temp, hormone levels, buffers min.change, stroke volume (amount of blood ejected out) ETC.. Protects: immune system and blood clotting |
|
How much of the heart is toward the left side of the body?
|
2/3rd
|
|
during conception, which week does the heart start beating?
|
3rd week of development
|
|
How many times does your heart beat in an average lifetime?
|
8 billion times
|
|
Deoxygenated blood gets pumped through which part of the heart first?
|
To Left Atrium, to the Left valve which pumps it to the entire body.
|
|
Pulmonary circulation starts at what part of the heart?
|
*at the right ventricle all the way to the Left Atrium.
|
|
Blood flows through what part of the heart First?
|
*right atrium, to right ventricle
|
|
Pulmonary circulation
|
*source comes from the RA
*arteries are pulmonary and 02 content in arteries are low *veins are pulmonary and 02 content high *termination is on the LA |
|
Systemic Circulation
|
*source is on the LA
*Artery is the aorta and its branches, and the o2 content is high *Veins are superior and inferior vena cava and their branches, and 02 is low *termination is the RA |
|
Some Characteristic of the heart?
|
*intercalated discs
*gap junctions *collateral circulation |
|
What is the blood supply and oxygen uptake of the heart?
|
*250 ml of blood during rest/min
*1/20 of cardiac input *max amount of oxygen that can be extracted is 85% (during exercise or when heart is having problems) |
|
What happens to you heart during exercise?
|
*Cardiac output increases by 4-5 times
|
|
What is the hearts weight relative to body weight?
|
1/200
|
|
What is considered the fuel of the heart?
|
*fat: primary source of energy, can also be glucose (but lesser extent)
*lactic acid or other fuel that is available *need o2 because heart id highly aerobic |
|
What does functional syncytium mean?
|
*heart working as a single unit (all for one, one for all) in order to pump blood.
*parts cannot work as independent units |
|
Frank-starling law
|
Heart will pump any amount of blood that comes to it. When more blood comes at it, heart will contract more forcefully
|
|
How does the heart handle contractions?
|
* the elasticity of the heart rebounds in greater force than the skeletal muscle
*when it gets stretched it rebounds quickly |
|
What are the cardiac tissue layers?
|
*epithalial tissues covers the surfaces
*Endocardium (endothelium): inner layer *Myocardium: middle layer *epicardium: outer layer *the middle parts (pericardial cavity and the parietal layer) are lubricated for better slipping etc. |
|
What is considered to be the pace setter of the heart?
|
The SA(Sinoatrial Node) node
*due to generating AP's the fastest rate and also is the 1st signal |
|
What are the electrical signals at auto-rhythmic cells in the heart? (conducting systems of the heart)
|
*99% makes up the contractile function (generated by auto-rhythmic cells); produce force.
*1% makes up conducting systems that do not produce force |
|
What do the conducting systems of the heart do (auto-rhythmic) ?
|
* makes sure electrical impulses are spread through the heart
*speeds up contraction *all cells of conduction are arhythmic (can produce AP's by there self) |
|
Does the Atria contract before the ventricles?
|
yes
|
|
Inter nodal Pathway?
|
*makes sure electrical signal is taken so the heart can contract simultaneously
*makes sure signals get to the AV node *coordinates contraction |
|
Inter atrial pathway...
|
is between the atria
|
|
Does the Left side of the heart contract the same rate as the right side?
|
yes
|
|
What is the average heart rate that the SA node produces?
|
*70-80 beats per min
|
|
Can the pace maker change?
|
*yes, if the heart gets excited from anxiety,stress, drugs etc. The "pace setter" changes for the AP's that are the fastest rate.
|
|
Myologenic?
|
electrical signals by heart that relies on external stimulation
|
|
Term used when the heart is in resting phase?
|
*diastolic phase
|
|
Term used when the heart is in a cardiac cycle phase? (not resting)
|
*systolic phase
|
|
When the atria and the ventricles are relaxed (diastolic phase) how much blood can possibly fill the ventricles?
|
*70% of ventricles fill possibly without any contraction
(during contraction ventricle pushes 30% more blood) |
|
During Atria contractions, how much blood gets filled up?
|
*30% more blood gets pushed, and NEVER will fill whole ventricle
|
|
ECG
|
*electrode attached to wrist and arm which measures the electrical current going through your body, and is measured on the surface of your skin
|
|
What is the AP duration of a cardiac cell?
|
*1/4 a second (250 milla seconds.)
|
|
In a ECG (QRS) There are 2 electrical events that take place...
|
1) repolarization of atria
2) depolarization of ventricles |
|
During the T-wave in the ECG, what electrical even happens?
|
repolarization of the ventricles
|
|
During the P-wave in the ECG, what even t takes place?
|
depolarization of the atria
|
|
What is the resting membrane potential in atrial cells?
|
-90
|
|
When does Atrial Contraction happen in the ECG? (systolic phase)
|
*P-QRS
|
|
When does the systolic phase of the ventricles happen in the ECG?
|
*QRS-T
|
|
When is the diastolic phase of the entire heart (ECG)?
|
T-P
|
|
When is the diastolic phase of the ventricles in ECG?
|
T-QRS
|
|
What is the normal discharge rate for the AV node?
|
40-60/min
|
|
What is the normal discharge rate for spontaneous discharge (bundle of His) ?
|
*35/min
|
|
What is the normal discharge rate for Purkinje Fibers?
|
30/min
|
|
What are the three factors for spontaneous depolarization (auto-arhythmic)?
|
1) Na+ ion comes into cell
2) K+ permeability lowers (hyperpolarization; cell becomes +ive) 3) Ca++ ions also come into the cell |
|
What happens to heart rate during parasympathetic phase?
|
*heart rate decreases
*Na+ increases in permeability; hyperpolarization |
|
`What happens to heart rate during sympathetic phase?
|
*HR increases (releasing adrenalin)
*permeability of Na+ decreases |
|
In contractile cells depolarization and the threshold are where?
|
*depolarization begins at - 60
*threshold is at - 40 |
|
What ion is responsible for the plateau affect in contractile cells?
|
*Ca++ ions slowly comes into cell allowing AP's to become prolonged
|
|
Why is it important to prolong the AP's for contractile cells?
|
*ensures that cardiac cell only generate twitches.
*produces refractory periods which omits wave summation or tetnus from happening |
|
Myocardial cells have RMP of what in mV?
|
*-90 mV
|
|
Depolarization to threshold by AP's originating in what node?
|
*SA node
|
|
Is contraction time of a twitch the same amount of time as an AP?
|
*yes 1/4 of a second to be exact (250 mill.sec)
|
|
Latent Pace makers?
|
*All other arhythmic cells can become latent pace makers except SA node
*when SA fails, latent pace maker takes over (usually AV node). |
|
Tachycardia
|
*an abnormality in heart beat
*hear rate beats more than 100 times per min |
|
Bradycardia
|
*an abnormality in heart beat
*when the heart rate is beating below 60 per min |
|
Arrhythmia
|
*an abnormality in heart beat
*irregular heartbeat (without the normal rhythm |
|
Ectopic focus
|
An abnormally excitable area
(something either than SA node beating the pace maker ; the slower engine picking up speed than surpassing the SA node ( which once was fastest). |
|
Premature beat (extrasystole)
|
*from ectopic focus
*frequently responds in response to anxiety, lack of sleep, excess caffeine , nicotine, or alcohol consumption. |
|
When does a complete heart block occur?
|
*usually AP's are not transmitted through AV node due to malfunction.
*when the conducting tissues between the atria and ventricle is damaged and becomes nonfunctional |
|
What is the first sound that the heart makes?
|
*Lub; closure of AV valves (bi/tricuspid)
|
|
What makes the second sound of the heart?
|
*Dub; closure of the semilunar valve
|
|
How do you calculate cardiac output?
|
* CO (Q) = HR (heart rate) times SV (stroke volume)
|
|
What is cardiac reserve?
|
*how much cardiac output you can increase above resting CO.
Example: 25L - 5L= 20L cardiac reserve |
|
How do you calculate Blood pressure?
|
BP= CO times Peripheral resistance (resistance to blood flow, hinderance)
|
|
What is the average amount of blood pumped into the heart per min during resting cardiac output?
|
*5L
|
|
What is the average amount of blood pumped into the heart per min for an average world class athlete?
|
*40 L
|
|
What is the average amount of blood pumped into the heart per min for an average person working out?
|
*20-25L
|
|
how much volume can you increase going into the heart per min when you work out?
|
*about 1/2 L
|
|
How does the sympathetic N.S affect HR?
|
*increases BP, CO, and HR with the use of epinephrine and norepinephrine
|
|
How does the parasympathetic N. S affect HR?
|
*HR, CO, and BP decreases (actelcholine releases)
|
|
How does Stress affect HR?
|
*stress activates sympathetic N.S which increases BP,CO, and HR
|
|
Peripheral resistance?
|
*is based on restriction of blood vessels (become narrower; constricts)
|
|
What is the term used when blood vessels become wider or narrower?
|
*narrower= constriction
*wider= dilation |
|
Is the diameter of blood vessels static or dynamic?
|
*dynamic
|
|
What percentage of blood goes in our veins?
|
*60-70%
|
|
when there is extra blood that is constricted by the blood vessels, where does it go?
|
*the heart of course!
|
|
What is the equation of Systolic Volume?
|
SV= EDV - ESV
(End diastolic volume - End systolic volume) Ex) 70mL= 135mL-65mL |
|
What is ESV?
|
*End Systolic volume
*end of contraction force *blood remaining in the ventricle after its been contracted |
|
What is EVD?
|
*End diastolic Volume
*volume of blood at the end of diastolic phase of the ventricle (just before it contracts; filling the ventricles) |
|
Venous return?
|
narrows veins so extra blood gets pushed into heart
|
|
During stroke volume, what happens to the blood?
|
*40% blood remains in the ventricles
*60% of increasing volume is sympathetically ejected |
|
When the blood is returning to the heart (by the greater venous return), what is it done by?
|
*by the Bainbridge (atrial) reflex; both atrium
|
|
What hormone is the single most important for resting metabolic rate?
|
*thyroid hormones
Ex) fever increases= increase in HR, CO, and BP |
|
What does Nicotine and Caffeine do to your HR?
|
*increases HR, BP, and metabolic rate
|
|
WHen you get older, what happens to your heart rate?
|
*HR decreases
|
|
The bigger the person, the slower the hear rate?
|
True
Ex) ave heart beat of an elephant per min = 25 beats/min |
|
Biological rate doubles after the temperature increases by what?
|
*10 degrees
|
|
Factors affecting SV?
|
*sympathetic N.S
* EDV (anything that affects this= increase in BP and CO) |
|
What is the pressure gradient of blood?
|
*blood goes from high to low pressure
|