lecture 1: Guyton chapter 9 Flashcards
heart is apprx the size of your…
fist
what is the location of the heart
Superior surface of diaphragm
Left of the midline
Anterior to the vertebral column, posterior to the sternum
true or false: the left and ride side of the heart are the saem
false; they are anatomically and functuonaally seperate
what does it mean for the heart to be a dual pump
right=lungs
left=systemic
what ensures that the blood from the left and right side of the heart does not mix.
The interventricular septum
true or false: even if the left adn right sides are sperated, the heart contracts in a coordinated fahsion?
expalin
truwe
the atria contract together and the ventricles contract together….
the left side of the heart is coupled in///
parrallel
blood goes to diff capilaries depending on where its needed
the right side of the heart is coupled in …
series
only goes from heart lungs and back top heart
which side is a low pressure system
right sife
which side is a high opressure ssytem
left
why is the left side a high pressure system
mut overcome systemic pressure
explain the pathway of blood though the body
1) O2 deficient blood returns from body via sup and inf vena cava
2) enters right atrium
3) enters right ventricle
4) goes to puilmonary artery
5) goes to lungs
6) blood is oxygenated
=PULMONARY CIRC.
7) blood comes back through pulmonary veins
8) blood goes to left atrium
9) blood goes to left ventricle
10) blood goes to aorta
11) circulatets to the body
=systemic circualation
what is the lining that covres the heart
pericardium
what is the pericardium
a double walled sac around the heart
what are the 2 layers of pericardium
1) superficial fibrous pericardium
2) a deep 2 layer serous pericardium
what are the 2 layers of the deep serous periodcardium
parietal layer and vsiceral layer
where does the parietal layer line
the interal surface of the fibrous pericardium
where does the vsiceral layer line
lines the surface of the heart
what is another name for the visceral layer
the epicardium
what are the visceral and parietal layers serpated by
fluid filled pericardia cavity
what are the.3 fucntions of the pericardium
Protects and anchors the heart
Prevents overfilling of the heart with blood
Allows for the heart to work in a relatively friction-free environment
what allows Allows for the heart to work in a relatively friction-free environment
the pericardial space that is fluid filled
what are the 3 types of cardiac muscle
atrial muscle (the chambers that receive the blood) ventricle msucle (chambers that eject special excitatory and conductive msucle fibers
what is the difference between cardiac and skeletal muscle cotnraction
Atrial and ventricular types of muscle contract in much the same way as skeletal muscle
However, the duration of contraction is much longer
why is heart muscle contraction longer than sksetla msucle
heart needs time to fill after blood ejection
true or false: cardiac msucle is smooth
false its branched and striated
wher eis the nucleus of cardiac muscle
centrally located
what are muscle cells of the heart called
myocutes (cardiomyocytes)
or myofibrils
what is the outside membrane of the cardiac muscle caleld
sarcolemma
true ro false: Cardiac muscles have the same arrangement of actin and myosin, and the same bands, zones and Z discs as skeletal muscles forming sarcomeres.
true thats what make it straited
which has less sarcoplasmic reticulum: cardiac or skeletacl
cardiac
where does cardiac muscle get its calcium from and why
from extracellular flued for contraction (they have large t tubyles)
beacuse lsss sarcoplasmic retulum
which has larger T tubule diamters: cardiac or sckeletal
cardiac (5 times greater diameter0
what does it mean for cardiac muscle to act as a syncytium
cardiomytocites are electrically connected to the next cell
coordinated contraction of muscles along their entire length
true or false: Cardiac muscle fibers are made up of many individual cells connected in series
false
in series AND and in parallel with one another
explain intercalated disks
cell membranes separating and anchoring individual muscle cells from one another
At each intercalated disc, the cell membranes have fused
at the intercalated disks, the cell mebranes are smoothe>
false
they are rough which allows for increased surface area