Chapter 21: Cardiovascular system and Heart Flashcards
describe the cardiovascular system (4)
Vital for survival
Carries oxygen & nutrients to tissues
Carries wastes away from tissues
Closed system
the cardiovascular system is a double circuit. What are the two circuits? describe them
- ) Pulmonary
- Heart to lungs & back
- Oxygenates blood - ) Systemic
- Heart to body & back
- Delivers oxygen to tissues
describe the structure of the heart (5)
- Cone shaped
- Inside pericardial cavity
- inside mediastinum
- apex tipped toward the inferior and left
- base superior
describe the membranes of the heart
Pericardium -double serous membrane with fibrous coat -made of several layers Parietal pericardium -outer layer of sac -Fibrous and areolar layer Epicardium -A.k.a. visceral pericardium -inner layer of sac -Adheres to the heart wall
where is the pericardial cavity located and what does it contain?
located between membrane layers and contains serous fluid
what three things are in the wall of the heart/ make up the wall of the heart?
Epicardium, Myocardium, Endocardium
describe the epicardium (2)
visceral pericardium
functions as protective outer layer
describe the myocardium (3)
middle layer
responsible for contractions
made of cardiac muscle
describe the endocardium (3)
inner layer
lines & protects chambers & valves
continuous with endothelium of heart blood vessels
describe cardiac muscle tissue (5)
striated aerobic respiration short T-tubules autorhythmic connected mechanically & chemically -intercalated discs -gap junctions
how many chambers are there in the heart? what are they
4 chambers
- 2 atria (right and left)
- 2 ventricles (right and left)
describe the atria (3)
superior chambers
receive blood from veins
have auricles (flaps where blood pools)
describe the ventricles (2)
inferior chambers
force blood out to arteries
what are the structural differences between the right and left ventricles?
Left thicker & stronger
Right goes only to lungs
Left is round
Right pouch shaped
describe the two atrioventricular valves
Tricuspid valve -aka right AV valve -at right atrioventricular orifice -open when atrial force is greater & close when -ventricular force is greater -3 cusps Bicuspid (mitral) valve -aka left AV valve -at left atrioventricular orifice -2 cusps
what are the “heart strings” called? describe them
Chordae Tendonae
- hold valves in place
- attached to cusps on ventricle side