what is the name of the fibrous sag that surrounds the heart?
the pericardium
what characteristics do cardiac and skeletal muscle share?
slow twitch fibers
striated muscle fibers
voluntary control?
what are the differences between cardiac muscle and skeletal muscle?
skeletal muscle does not have autonomic nerve fibers
cardiac is slow twitch
how many atria and ventricles are there within the heart?
there are two atria – left and right
there are two ventricles – left and right
which of the ventricles are larger? The left or the right
Why is this side larger?
the left
Because the left ventricle has to pump blood throughout the body
explain blood circulation throughout the heart and lungs,be sure to name the valves, arteries, and veins.
right atrium – tricuspid valve – right ventricle – pulmonary valve – pulmonary artery – lung capillaries – pulmonary vein
Left atrium – left valve – left ventricle – valve – aorta – arterioles
Capillaries – venules – veins – superior and inferior vena cava – right atrium
how are veins different from arteries?
no smooth muscle
venis have one-way valves
true or false – veins can contract when stimulated by the sympathetic nervous system.
true
the right and left coronary arteries begin at the base of what arteries?
aortic
when does a heart refill with blood?
during diastole
what is the function of arterioles?
resistance vessels
regulate blood flow to tissue
what is a function of capillaries?
capillaries are areas gas exchange
what is a function of veins?
capacitance/storage system
carry deoxygenated blood back to the heart
heart rate regulation
explain intrinsic regulation
pacemaker – electrical impulse conduction system
heart rate regulation
Explain extrinsic regulation
autonomic nervous system
what two nerves regulate heart rate?
the vagus nerve– parasympathetic
cardiac accelerator nerve???
SA node is the_______ of the heart
pacemaker
normal heart rate ranges from?
60 – 100 bpm
true or false – the AV node is a backup pacemaker of the heart
true
what is another name for Purkinje fibers
bundle of his
How come is the SA node the pacemaker of the heart and not the AV node?
because the nerve is faster for the SA node
explain the depolarization of the heart
SA node – AV node – bundle of his– right and left bundle branches – Purkinje fibers
true or false – the vagus can slow heart rate
true
what happens during diastole?
refilling/relaxation phase of the heart
what happens during systole
contraction of the heart
what happens during the P wave of an EKG?
atrial depolarization
what happens during the QRS of an EKG?
ventricular depolarization
what happens during the T wave of an EKG?
repolarization of the ventricles
how does a cardiac accelerator nerve affect the heart
this nerve innervates SA node in the ventricles of the heart and has sympathetic nervous system input
true or false – the vagus nerve innervates only the AV node of the heart
false – the vagus nerve innervates both AV node and SA note and has parasympathetic nervous systems and put
true or false – heart rate during exercise initially increases at the beginning of exercise primarily due to decreased PNS tone
true
true or false – after approximately 35 seconds, the heart rate will increase by sympathetic nervous system input,
true – this is due to feedback from muscle and joint receptors as exercise begins
what is the value for the mean arterial blood pressure
96 mmHg
what is the formula for mean arterial blood pressure
MABP= DBP +.33 (SBP-DBP)
what are major factors that influence blood pressure
peripheral resistance
blood viscosity
blood volume
heart rate
stroke volume
body position, body weight, etc.
true or false – blood pressure is higher while standing up
false – blood pressure is higher while laying down
how is blood pressure regulated in the short term aspect
by the baroreceptors located in the carotid and aortic arteries
house blood pressure regulated in the long-term aspect of things
the kidneys regulate blood volume via fluid output through electrolytes and hormone effects – sodium, aldosterone, ADH
explain the baroreceptor reflex
the baroreceptors in the carotid artery recognizes the low blood pressure and send signals to theCVCC in the medulla oblongata of the brain.. CVCC adjusts sympathetic nerve activity (SNS) two the peripheral vessels ( arterioles and veins) four vasoconstriction and hard to increase heart rate in contract ability; all help to return blood pressure back to normal
how can you prevent orthostatic hypo tension
drop legs off to the side
deep breathing
active muscle contractions
What is the difference between stroke volume and cardiac output?
Stroke volume: amount of blood ejected per contraction (mL/beat)
Cardiac output: amout of blood pumped by heart per minute
What are 6 things that influence BP (if something goes up, BP goes up... if something goes down, BP goes down)
peripheral resistance
blood viscosity
blood volume
heart rate
stroke volume
body position/weight/wize
What is the only type of exercise that increases DBP?
Resistance- heavy isometric
(SBP also goes up, but may temporarily decreses to levels slightly below exercise levels)
At rest what is occuring with the blood flow?
Low blood flow (15-20% Q) to skeletal muscles becase us SNS stimulation causing vasoconstriction
In anticipation of exercise what occurs with the blood flow?
ACH is released into skeletal muscle by heart and SNS cholinergic fibers to dilate blood vessels
Once exercise begins, SNS causes vasoconstriction
Which individual has the highest SV during exercise?
fit individual
sedentary individual
individual with heart failure
Fit individual
If patients are HTN what should you try to do?
avoid heavy loading resistance
consider bouts of 10 minutes exercises
What are two things that regulate stroke volume?
venous return: increases during exercise because of wasoconstriction, muscle pump, and respiratory pump
afterload: the impediment to ejection of blood from heart
What happenes to Q, SV, and HR with prolonged exercise?
Q stays constant
SV declines
HR increases
What are some CV benefits of exercise?
^ efficiency of heart
beats slower, but ejects mores
slower heart rate = less oxygen for heart
decreased SBP and DBP at rest
What are blood/vascular changes with exercise?
# of RBC's ^ which means Hgb ^ which menas oxygen carrying capacity ^
plasma volume and total blood volume ^
hematocrit (% of cells in volume of blood): blood cells ^ but blood volume ^ more, so hematocrit decreases
favorable clotting characteristics because of low platelet adhesives
Aerobic exercises cause restriction in what:
^ HDL
decrease serum triglycerides
small to no reduction in LDL
total body fat
reduces intra-abdominal fat
reduces insulin needs, improves glucose tolerance
In aerobic/endurance training what happens to the heart? What happens in resistance training?
The left heart enlarges in diameter so volume capacity is greater. The diamter of ventricle increases equal to the hypertrophy of the ventricle.
Resistance training causese the same hypertrophy of the walls but the diameter does not increase- therefore increasing pressure (why heavy resistance training would be good for someone with coronary heart disease)
