Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Physio1 Exam2
| Question | Answer |
|---|---|
| Define Frank Starling Law | Volume of blood ejected by the ventricle is dependent upon the volume present at the end of diastole **volume the heart ejects in systole equals the volume it receives in venous return |
| Preload? | Depends upon the LV end diastolic volume (EDV) |
| Afterload? | Depends upon aortic pressure |
| Stroke volume and cardiac output correlate directly with? | End diastolic volume |
| End diastolic volume correlate directly with? | Venous return |
| IsoVol-R? | Drop in pressure but not in volume |
| IsoVol-C? | Heart contracts but valve is still closed |
| Vent Eject? | High pressure, decreased volume in ventricle |
| What are the two components to CARDIAC MINUTE WORK? | Volume work and pressure work |
| Pressure work? | Cardiac output x aortic pressure |
| Myocardial oxygen? | Pressure work is far most costly than volume work |
| What is the driving force for blood flow? | Mean arterial pressure (Pa) |
| Positive chronotropic? | Increase in heart rate |
| Negative chronotropic? | Decrease in heart rate |
| Equation for Pa (mean arterial pressure)? | Cardiac output x TPR |
| What are the regulatory mechanisms for Pz? | Baroreceptor reflex, Renin angiotensin system |
| Mechanoreceptors? | Sensitive to stretch and pressure |
| Where are mechanoreceptors located? | Carotid sinus and aortic arch |
| What are mechanoreceptors more sensitive too? | Change in pressure and RAPID change in arterial pressure |
| What is activated in Cushing reaction? | Central chemoreceptors |
| What happens in cushing reaction? | Intense vasoconstriction in the body to direct blood from to the brain |
| Microcirculation? | Blood flow in capillaries |
| Autoregulation of blood flow is done by? | Vasoconstriction and vasodialation (local blood flow control) |
| Active hypermeia? | Increase in blood flow to an organ that has increased metabolic demand(local blood flow control) |
| Reactive hypermeia? | If a body tissue is without 02 then the body will repay the O2 debt(local blood flow control) |
| Myogenic hypothesis? | Explains autoregulation. When vascular smooth muscle is stretched, it contracts |
| Metabolic hypothesis? | Explains local control of blood flow. Alters resistance of the arterioles so that O2 delivery to a tissue can be matched to P2 consumption of the tissue |
| Examples of vasodilator metabolites? | Lactate, CO2, H, K, adenosine |
| What are vasodilator metabolites found? | Metabolic hypothesis |
| Peripheral chemoreceptors? | O2 decreases->activates sympathetic->arteriolar vasoconstriction and increase in parasympathetic outflow to the heart and produces decreased heart rate |
| Central chemoreceptors? | Sensitive to PCO2 and Ph->increase in sympathetic activity |
| The carotid sinus baroreceptors are responsive to what kinds of pressure? | An increase OR a decrease |
| The aortic arch baroreceptors are responsive to what kinds of pressure? | Primarily to an INCREASE |
| T/F: Baroreceptors are mechanoreceptors? | True |
| The baroreceptors effect the parasympathetic by? | Vagus N on the SAnode to decrease heart rate |
| The baroreceptors effect the sympathetic by 4 things? | (1) effect on SAnode to INCREASE heart rate (2) effect on cardiac muscle to INCREASE contractility and stroke volume (3) effect on arterioles to produce vasoconstriction and INCREASE TPR (4) effect veins to produce venoconstriction and dec unstressed vol |
| Hemorrhage produces a decrease in Pa bc? | As blood volume decreases, stressed volume also decreases |
| Baroreceptor in response to hemorrhage does what? | Decrease in Pa->decreased stretch on baroreceptor->decreased firing rate of the carotid sinus N |
| Give examples of vasoactive substances? | Histamine, bradykinin, serotonin |
| Prostaglandins (PGE) produce? | Vasodilation |
| Thromboxane A2 produce? | Vasoconstriction **From platelts |
| Angiotensin II and Vasopression produce? | Vasoconstrictiors |
| Atrial natriuretic peptide does what? | Is secreted in atria in response to increase arterial pressure and causes vasodilation *Promotes Na EXCRETION** |
| The first heart sound is made from what? | Closure of the AV valves |
| The second heart sound is made from what? | The aortic valve closes slightly before the pulmonic valve |
| Barorecptors are located in what two places? | Carotid sinus and aortic arch |
| Renin converts ____ to _____ | Angiotensinogen to angiotensin I |
| Signals from the barorecptors report to the ___ | NTS - Medulla |
| Function of aldosterone is to reabsorb ___ ions? | NA |
| ADH acts on 2 receptors that are responsible for ___ and ___ | Vasoconstriction and increase water permeability |
| Examples of vasodialator metabolite is | CO2, lactate, histamine, H, K |
| In response to high blood pressure, there is a __ in parasympathetic activity and a ___ in sympathetic activity | Increase in para and a decrease in symp |
| What enzyme converts AngI to AngII | ACE |
| When myogenic muscle stretches, it? | Contracts |
| What hormone promotes NA secretion? | AMP * |
| Starling forces that promote filtration? | Pc & pie-i |
| What side of the heart carries O2 blood? | Left |
| What side of the heart carries DeO2 blood? | Right |
| Majority of the arteries like the aorta carry 02 blood EXCEPT the? | Pulmonary A, it carries De02 blood |
| Majority of the veins like the vena cava carry De02 blood EXCEPT the? | Pulmonary V, it carries 02 blood |
| What valves are located on the L side of heart? | Mitral valve |
| What valves are located on the R side of heart? | Tricuspid valve |
| Define cardiac output? | Amount of blood that is pumped into circulation(body) per min |
| How much blood is pumped per min in body? | 5L per min |
| What are the three mechanisms for blood flow change? | (1) cardiac output remains constant but blood flow is redistributed (2)cardiac output increase or decreases and blood flow among the organs is kept constant (3)combination of the two above |
| Blood that comes back to the heart is none as? | Venous return |
| Blood in the arteries is known as? Why? | Stressed volume. Because the heart pumps blood into the arteries |
| What do arteries have more of than veins? | Arteries have more elastic tissue and they are thick walled |
| Veins have the ability to? | Stretch and pool blood |
| Blood in the veins is known as? | Unstressed volume |
| Where does gas exchange take place? | In capillaries |
| Alpha1 and beta2 are what kind of receptors? | Sympathetic. Known as Adenergic receptors |
| Adenergic receptors are ? what do they respond to? | Alpha 1 & beta 2. They respond to adrenaline |
| What does alpha 1 do? | Constriction |
| What does beta 2 do? | Dilate |
| Capillaries have the biggest? | Surface area but little blood |
| Veins have more? | Blood bc thin walled, less elastic tissue, giving them the ability to have more compliance |
| Blood always flows from? | High pressure to low pressure |
| If you increase resistance, what happens to blood flow? | Decreases (vasoconstriction) |
| If you decrease resistance, what happens to blood flow? | Increase (vasodilation) |
| Define laminar blood flow? | Velocity on side of blood vessels is zero. Max velocity in the center |
| Normal blood pressure? | 120/80 |
| How to find MAP (mean arterial pressure)? | Diastolic+ 1/3 of pulse pressure |
| What is pulse pressure? | Systolic-diastolic |
| Heart spends most of its time in? | diastolic (relaxation) |
| Where is the largest drop in blood pressure? | In the arterioles |
| Define contractile cells ? | Majority of atria and ventricular tissues and are the working cells of the heart. GENERATE ATP |
| Define conducting cells? | Constitute the tissues of the SA/AV node. They don't contribute to generation of force but more to rapidly spread action potentials over the entire myocardium |
| Who is the pacemaker of the heart? | SA node- the SAnode has the ability to generate action potentials by itself without and neuro input from the brain |
| What are the two kinds of pacemakers? | Temporary and permeant |
| Define Frank Starling Law? | Length tension relationship. The more the heart stretches, the more it will contract |
| The pacemaker is a collection of? | Conducting cells |
| What does the heart use for energy? | Fats |
| Define overdrive suppressing? | SA node take the lead by suppressing the other pacemakers |
| Define ectopic pacemaker? | Latent pacemaker can take over if SA node is suppressed |
| Does SA node have a plateau? | No |
| Does ventricle have a plateau? | Yes |
| What kind of cell is SAnode? | Conducting |
| What kind of cell is ventricle? | Contractile |
| What kind of membrane potential does the SA node have? | UNstable resting membrane potential |
| What kind of membrane potential does the Ventricles have? | Stable resting membrane potential |
| What type of Ca channels does SA node have? | T type Ca channels |
| What type of Ca channels does the ventricles have? | L type Ca channels |
| Where is the AP from in SAnode? | Action potential made by itself |
| Where is the AP from in the ventricles? | Needs an AP from the SAnode |
| Beta1 receptors deliver? | POSITIVE chronotropic effects |
| Muscarinic receptors deliver? | NEGATIVE chronotropic effects |
| Chronotropic=? | Heart rate |
| Ionotropic=? | Contraction |
| Dromotroic=? | Conduction velocity |
| What are the parasympathetic receptors? | alpha1, alpha 2, beta1, beta 2 |
| What are the sympathetic receptors? | Nicotinic, muscarinic M2 |
| Conduction velocity depends on? | The size of inward current and the upstroke of the action potential |
| Define heart block? | Conduction velocity via the AV node is sufficient decreased. AP maybe not be conducted at all or insufficiently conducted from atria to ventricles |
| IN the sympathetics, what effects the contraction of the heart? | Beta receptors |
| In parasympathetics, what effects the contraction of the heart? | Muscarinic receptors only on the ATRIA |
| What do muscarinic receptors on the atria do? | Decrease I-Ca and increase in I-K outward current |
| Increase heart rate=? | Increase contractility |
| Define stroke volume? | Volume of blood ejected per beat (70mL) EDV-ESV |
| Define ejection fraction? | Fraction of end diastolic volume ejected in each stroke volume (55%) SV/EDV *Indicator of contractility |
| Define Cardiac output? | Total volume ejected by the ventricle per unit time SVxHR |
| Define EDB? | Amount of blood in the ventricles before ejection |
| Define ESV? | Amount of blood in the ventricles after ejection |
| Define cardiopulmonary low pressure baroreceptors? | Veins, atria, pulmonary arteries-detect changes in the blood volume and return blood volume to normal |
| Define bainbridge relfex | Pressure atrial or venal receptors are activated by increase in pressure that sends info to the nucleus tractus solitarius in the medulla to increase in renal perfusion and finally increase in Na and water excretion |
| Lymphatic capillaries lie in the? | in the interstitial fluid and possess one way flaps |
| What are the two mechanisms for blood flow? | Local control and nerual/hormonal control |
| Coronary is controlled by? | Mostly local metabolite such as hypoxia (increase in O2 demand) and adenosine (vasodialtion) *reactive hyperemia |
| Cerebral is controlled by? | Controlled by local metabolites such as increase in CO2 cause vasodilation of the cerebral arteries |
| Control of skeletal? | Both local metabolites (lactate, K) and sympathetic innervation (alpha 1, beta 2) *reactive hyperemia |
| Control of skin? | Dense sympathetic innervation, very little role of local metabolites, only during trauma |
| Temp regulation of heat generation? | Thyroid hormones, sympathetic nervous system, shivering, behavioral |
| Temp regulation of heat dissipation? | Decrease sympathetic activity in the skin blood vessels but increase activity of sympathetic cholinergic fibers (sweating), shunting of blood in veins, behavioral |
| Define heat exhaustion? | Occurs in response to elevated environmental temp and can result from excessive sweating |
| Define heat stroke? | Sweating does NOT occur and body temp increases to the point of tissue damage |
Created by:
wizdumbslp
Popular Chiropractic sets