Week 1 CV and A&P Flashcards
Thoracic cavity
12 sets of ribs
sternum
thoracic vertebrae
houses abdominal organs
maintains negative pressure for lunch function
Thorax
covers vital organs of the thoracic cavity including the heart, lungs, and esophagus
What is the floor of the thoracic cavity?
Diaphram
Where is the mediastinum located?
btw pleurae of the lungs
What does the mediastinum contain?
non-pulmonary thoracic viscera: heart, vessels/vasculature, esophagus, trachea, thymus, thoracic duct, associated lymph nodes, neural structures (phrenic nerve)
What are the borders of the mediastinum?
chest wall, lungs, spine, diaphram
The heart pumps blood the the body via
vascular system
Pericardium
fluid-filled sac surrounding the heart; 2 layers including parietal (fibrous) and visceral (serous) pericardium
What are the three layers of the heart
endocardium - innermost layer
myocardium - muscular layer
epicardium - visceral pericardium
Myocardium
comprised of myocytes and intercalated disc
Can the Myocardium replenish itself if cell death occurs?
no
Myocardium the key function
conductivity
rhythmicity
automaticity
Myocytes
containing actin, myosin, large # of mitochondria for ATP production
intercalated disk
syncytium - desmosomes and connexin
Endocardium
simple squamous and areolar tissue; line chambers, vales, blood vessels
Epicardium
Visural pericardium, with some adipose mixed in; arteries, lymphatic, veins run underneath this layer
Two-walled layer surrounding the heart and its vessels
pericardium
Pericardium parietal layer
outer; dense connective tissue
Pericardium visceral layer
thinner layer continuous with epicardium
Pericardium contains 10 - 20 mL of pericardial fluid btw the 2 layers that serves to
decrease the amount of friction that occurs during contraction of the heart
Right atrium
contains pectinate muscles attached to anterior and lateral walls + auricles for increasing avail volume/capacity for blood
Left atrium
also has auricles; thicker walls as it receives higher pressures than R atrium; pectinate muscles into pulm veins to eliminate backflow
Right atrium receives
deoxygenated blood from superior and inferior vena cave, coronary sinus
Atrial kick
refers to the 15-20% of cardiac output that results from pectinate muscle contraction
Atria contains auricles to increase
available volume
Left atrium receives
oxygenated blood via pulmonary vein
Left atrium contains thicker walls than the right because
it receives higher pressures of blood from pulmonary circulation
The atriums are seperation by
interatrial septum
Right ventricle receives
deoxygenated blood from right atrium
Left ventricle
sends oxygenated blood through aorta and into systemic circulation
The left ventricle is the thickest walls of all chambers due to
volumes of blood and need for force/contraction
Ventricles are separated by
interventricular septum
Which ventricle is triangular shaped?
Right ventricle allowing large volume of blood to be ejected into narrow valve against low pressure gradient
Which ventricle is cone-shaped
left ventricle
Why does pressures matter?
Blood flow from high to low pressure gradient. Shapes of different chambers, wall thicknesses, valve size, appendages/extra structures all matter with regards to pathway and volume of blood flow.
Diastolic of R atrium
0-8 mmHg
Diastolic of L atrium
4-12 mmHg
Diastolic of R ventricle 0-8 mmHg
Diastolic of L ventricle 4-12 mmHg
Systolic of R ventricle
15-30 mmHg
Systolic of L ventricle
80-120 mmHg
Valves
only allow for unidirectional flow due to leaflets that are attached to the papillary muscle of the myocardium via chordae tendinae
Atrioventricular
eliminate backflow of blood during ventricular systole
tricuspid
mitral
Valve between R atrium and ventricle
tricuspid
Valve between left atrium and ventricle
mitral
Semilunar
eliminate backflow of blood during ventricular diastole
pulmonary
aortic
Pulmonary valve
btw right ventricle and pulmonary artery
Aortic valve
btw left ventricle and aorta
Superior vena cava
collects blood from head and UE
inferior vena cava
collects blood from LE and trunk
Coronary arteries
receive blood during diastole when aortic valve is closed
Right coronary artery
from aorta
Pulmonary veins
valveless; travel to L atrium
R coronary artery branches
posterior descending
SA nodal artery
Marginal artery
Posterior descending supplies
posterior 1/3 of interventricular septum
SA nodal artery supplies
SA node