A & P - HEART Flashcards
Pericardium layers
-Fibrous
-Serous
Heart muscle layer
myocardium
Auricle function
increase capacity of atria
Large veins that drain into right atria
-superior vena cava
-inferior vena cava
-coronary sinus
Pectinate muscles are found where?
Atria - in wall of right atrium
Trabeculae Carnea
muscles inside ventricles & convey electrical signals
(muscles that form ridges & convey electricity)
What valves connect right atrium to right ventricle
Tricuspid valve
Once blood has left the heart, what is the first branch off the aorta?
Coronary arteries
Mechanisms for valves to open & close in the heart
Pressure changes
2 Semilunar Valves
-Aortic
-Pulmonary
2 Atrioventricular Valves
-Tricuspid
-Bicuspid (mitral)
AV valves: how are they attached to wall of heart - what structure attaches them?
Chordae Tendineae
Papillary muscles relaxed, chrodae tenineae are slack, valves…
OPEN
Pulmonary Circulation: blood flowing from what chamber to what chamber?
right ventricle, into pulmonary trunk, into lungs
Systemic Circulation: blood flow
left ventricle, through aorta, aortic arch, descending aorta to be distributed through body
Branches of Coronary Arteries
-LEFT: anterior interventricular, circumflex
-RIGHT: posterior interventricular, marginal branch
Which veins drain into the coronary sinus?
-middle cardiac vein
-greater cardiac vein
-anterior cardiac vein
-small cardiac vein
Type of fibers for heart conduction system
Autorhythmic fibers
Name of test that measures electrical activities
ECG - electrocardiogram
Order of firing in conduction system
SA node, AV node, AV bundle of his, bundle branches, Purkinje fibers
On ECG, what does the QRS complex represent?
contraction of ventricles - depolarization of ventricles (contraction) & atria repolarization (relax)
P wave
depolarization of atria (contraction)
What starts the action potential in the myocardium of the heart?
SA node (natural pacemaker)
During depolarization, the action potentials stimulate what channels to open, and what rushes in?
Na+ - Sodium
What muscle moves food & urine in our body?
Smooth muscle
What is unique to cardiac muscle tissue
-desmosomes
-intercalated discs
-gap junctions
Where does cardiac muscle tissue get energy / ATP from?
Aerobic respiration
During ventricular systole, what are the ventricles & atria doing?
-ventricles = contracting
-atria = relaxing
Which cranial nerve slows down heart rate?
Vagus nerve X
Baroreceptors detect…
pressure & stretch - located in carotid artery
Chemicals that help regulate heart rate
-Epinephrine
-Norepinephrine
-Na+, K+, thyroid…
