chapter 18 cardiac output

cardiac output is estimated at ____ of blood pumped by the heart in ______

5 to 6 L, one minute

normal heart rate for a healthy individual is approximately _____

75 beats per minute

blood pressure normally found in the pulmonary trunk is approximately _____ of mercury

8 millimeters

_____ causes cardiac muscle to stretch

Venous return

_______delivers more blood to the _____ and more blood fills the ventricles which makes the ______ above the 120 ml estimate

Venous return, atrial Chambers, end diastolic volume increase

when intracellular calcium levels increase this enhances the interaction between ____ and ____ and ultimately enhances ventricular contraction for the force of contraction

actin, myosin

contractility is defined as the ____ achieved by_____. it's independent of muscle stretch or_____

contractile strengths, a given muscle length, preload

______ is inhibited by acidosis, increases in potassium as well as calcium channel blocker medications

contractility

is considered an extrinsic influence over stroke volume

contractility

resting skeletal muscle length represents when there's a maximal _____ attachment between _______

cross Bridge, actin and myosin

norepinephrine and epinephrine bound to receptors stimulate the production of _____ which will activate protein ____

cyclic AMP, kinase a

with exercise, the heart rate _____ because the delivery into the systemic and the pulmonary circuits are adequate due to the increase in ______

decreases, stroke volume

afterload is the force against which the ventricles must act in order to _____

eject blood

preload impacts the ______

end diastolic volume

______is approximately 50 ml

end systolic volume

if afterload increases it affect stroke volume by increasing the ____

end systolic volume

cardiac output is calculated by

multiplying stroke volume by heart rate

when the______ is dominant the heart exhibits vagal tone

parasympathetic nervous system

when we're not dealing with a stressful event and we need heart rate to be back to Baseline, it's the_____ that accomplishes this

parasympathetic nervous system

protein kinase a____ calcium channels and allow extracellular calcium to enter the cell.

phosphorylate,

is defined as the degree to which cardiac muscle is stretched before contraction

preload

the most important factor that affects stroke volume is _______

preload

the ventricles do not have to generate so much ____ to override the pressure that is found in the blood vessels to allow for the _____ and ventricular ejection to occur

pressure, semilunar valves to open

___________ contracts maximally at 80 to 120% of its optimal resting length

resting skeletal muscle

phosphorylation of the calcuim channels allow calcium that has been stored in the ____ to be released into the ____

sarcoplasmic reticulum, cytosol

cardiac muscle will not ______ unless forced

stretch to its optimal length

_________ is approximately 70 ml

stroke volume

__________reflects the volume of blood that's pumped out by one ventricle with each beat

stroke volume

another reason for increase in heart rate is the Bainbridge reflex. this is a _____ reflex that causes an increase in heart rate when the atrial cells stretch

sympathetic nervous system

when we're dealing with some type of issue with stroke volume or dealing with a stressful event it's the ______that will dominate

sympathetic nervous system

contractility increases due to the _____ innervation which causes ______ to bind to their adrenergic receptors on cardiac tissue.

sympathetic nervous system, norepinephrine and epinephrine

_______ is calculated by subtracting the amount of blood that's left in The ventricle after ventricular systole.

systole volume

______ is important because it basically balances The increased delivery of blood with ventricular ejection

the Bainbridge reflex

if heart rate increased alone, ultimately it would cause an increase in _____ that's left in the ____ after the ventricles contract

the amount of blood, ventricles

_______ is considered an extrinsic innervation because it's not something that is built into the heart itself like the intrinsic nodal system

the autonomic nervous system innervation

what is it if you subtract the end systolic volume from the total amount of blood that enter the ventricles during ventricular filling after atrial systole. it's approximately 120 ml.

the end-diastolic volume.

with exercise, a decrease in heart rate is due to an increase in stroke volume due to ______ and actually ejecting a little bit more then 70 ml each time the ventricles contract

the heart becoming more efficient,

there are changes in heart rate when the autonomic nervous system overrides ____when there are issues with _____

the nodal system, stroke volume decreasing

contractility is also increased by _____ and situations that increase extracellular calcium significantly

thyroxine and glucagon

the _____ is cranial nerve number 10

vagus nerve

more blood will be ejected from the ventricles during ____. the blood volume that's left is called the ____

ventricular systole, end systolic volume

stroke volume is when You __________ from _____ . this is how you come to the 70 ml stroke volume

Subtract 50 (esv), 120 ml (edv)

the cardiac output of the heart reflects the

amount of blood ejected from each ventricle in one minute

when the sympathetic nervous system dominates it will cause_____ and also

an increase in heart rate, contractility

in the ____ blood pressure is approximately 80 mm of mercury

aorta

in the Bainbridge reflex, the ________ stretch due to an increase in venous return

atrial cells

with heart rate, _____ cells are located in the _____ and the AV node

autorhythmic, sinoatrial node

heart rate also increases when your_____ increases

body temperature

________ exhibits a length tension relationship

cardiac muscle

_________indicates that our blood is making its way through both systemic and Pulmonary circulation in a short time

cardiac output

the_______ and _______ centers are both located in the medulla

cardioacceleratory, the cardio inhibitory

there can be ______ if the body is dealing with some type of stressful or responding to a particular stimuli

changes in heart rate

there are two things that increase venous return _______

exercise and the sympathetic nervous system

females have a _____ heart rate than males

faster

heart rate is the fastest in a ______ and tends to decline as we get older

fetus

the more that cardiac muscle is stretched the more

forcibly it will contract

afterload can become an issue when an individual has ____ and the pressures are higher and that means that the heart has to work harder

hypertension

afterload tends to be an issue for people who have _____and the pressure that's found in the aorta and the pulmonary trunk is _____ than normal

hypertension, higher

with heart rate, throughout the day both the sympathetic and parasympathetic nervous system is sending ______

impulses to the autorhythmic cells

cardiac muscle contracts ______when it's stretched______ and shorter length

maximally, Beyond its normal