Topic 12: Cardiovascular system Flashcards
Cardiovascular System
heart, blood vessels, blood
transport: gases, nutrients, hormones, wastes, heat
protection: disease, fluid loss (clotting
mediastinum
cavity where heart is
= space between lungs within thoracic cavity)
Pericardium
double-walled sac surrounding heart
List the 3 layers of the pericardium
a) fibrous pericardium
b) serous pericardium – 2 parts
i. parietal pericardium
ii. visceral pericardium (= epicardium)
fibrous pericardium
outermost layer = dense irregular CT
anchors to surrounding structures e.g. diaphragm, great vessels
(aorta, vena cava, etc
parietal pericardium
composed of epithelial and connective tissue
fused to fibrous pericardium (fibrous pericardium and
parietal pericardium = pericardial sac)
visceral pericardium
composed of epithelial and Ct
fused to heart surface, so is part of heart wall
pericardial cavity
between pericardial layers
- serous fluid (lubricates)
List the parts of the heart wall
a) epicardium
b) myocardium
c) endocardium
epicardium
stratified squamous epithelium and CT
myocardium
= cardiac muscle
arranged in spiral/circular pattern, reinforced with CT
endocardium
simple squamous epithelium and CT
epithelium named endothelium – lines inner surface of heart
and ALL blood vessels
Right Atrium
inferior and superior vena cava
coronary sinus (posterior)
Left Atrium
joined to 4 pulmonary veins
Right Ventricle
pulmonary trunk – divides to form 2 pulmonary arteries
* CARRY DEOXYGENATED BLOOD
Arteries
carry blood away from the heart
Left Ventricle
aorta
- thick b/c pumps blood to the body
Septa
separate chambers)
Interatrial septum
separates atria
Interventricular septum
separates ventricles
deep to interventricular sulcus (external
Fibrous Skeleton
CT fibers around the muscle fibers + CT rings between atria & ventricles at the
coronary sulcus
allows openings to remain open at all times (valves open + close)
provides electrical insulation – prevents simultaneous contraction of chambers
Atrioventricular (AV) valves:
i. bicuspid (mitral) valve
ii. tricuspid valve
bicuspid (mitral) valve
eft side – 2 cusps
tricuspid valve
right side – 3 cusps
LAB RAT (LEFT ATRIUM BICUSPID, RIGHT ATRIUM TRICUSPID)
Chordae tendineae
connective tissue) attach AV valve cusps to papillary
muscles (projections of myocardium)
o prevent eversion of cusps
Semilunar valves
3 cusps each i. aortic separates left ventricle + aorta ii. pulmonary separates right ventricle + pulmonary trunK
Cardiac Muscle Cells
form BOTH contractile myocardium + conduction system
List similarities to skeletal muscle
a) striated (myofibrils with sarcomeres)
b) has sarcoplasmic reticulum & T-tubules