Exam 2: Circulatory System Flashcards
Circulatory System =
Blood vascular system + lymphatic vascular system
Endocardium composed of
- Endothelium
- Looser CT layer
- More dense irregular CT
- Subendocardial layer
Endocardium endothelium type
Simple squamous
Endothelium: Looser CT + more dense irregular CT
Subendothelium
Subendocardial layer contains
Looser CT
Blood vessels
Nerve
Most purkinje fibers
Purkinje fibers
Modified cardiac myocytes
subendocardium Purkinje fibers characteristics
- Fewer myofibrils peripherally
- Stored glycogen
- Gap junctions and desmosomes
Subendocardium Purkinje fibers function
Conduct contraction impulse rapidly
Myocardium in atria
Less muscle
More elastic fibers
Myocardium in ventricle
More muscle
Intercalated discs parts
Transverse portion
Longitudinal portion
Transverse portions of intercalated discs
Macula adherens
Fascia adherens
Longitudinal portion of intercalated discs
Large gap junctions
Functions of intercalated discs
- Attach cardiac myocytes (macula adherens)
- Attach/stabilize myofibrils (fascia adherens)
- Cell-cell communication (gap junctions)
Specialized cardiac muscle cells
Myoendocrine cells
Myoendocrine cells secrete hormones that act on
Kidneys and renal arteries
Pericardium AKA
Serous pericardium
Epicardium AKA
Visceral pericardium
Parts of epicardium
Fibroelastic CT layer
Mesothelium
Fibroelastic CT layer of epicardium contains
Coronary vessels
Nerves
Sometimes adipose
Mesothelium of epicardium secretes
Serous lubricating fluid
Parietal pericardium parts
Mesothelium
Fibroelastic CT
Pericardial sac parts
Parietal pericardium
Fibrous pericardium
Fibrous pericardium contains lots of
Collagen I
Pericardial cavity is between
Parietal and visceral pericardium
Valve histology: endothelium w/
Dense irregular CT
**almost avascular
Cardiac skeleton made up of
Dense irregular CT
3 main components of cardiac skeleton
Annuli fibrosi
Trigonum fibrosum
Septum membranaceum
Annuli fibrosi locations
Base of aorta
Pulmonary artery
Openings of chambers
Trigonum fibrosum location
Cusps of aortic valve
Septum membranaceum location
Upper portion of interventricular septum
Function of septum membranaceum
Provide O and I for cardiac myocytes
Chordae tendinae CT type
Dense regular
Angina
Chest pain
Cause of angina
Slow narrowing of coronary vessels — less O2
Dysrhythmia
Abnormal heart rhythms
Dysrhythmia occurs when
Damage/death of Purkinje fibers
Pericarditis
Inflammation of pericardium
Tunica intima = continuation of heart’s
Endocardium
Tunica media = continuation of heart’s
Myocardium
Tunica adventitia = continuation of heart’s
Epicardium
3 types of arteries
Elastic
Muscular
Arterioles
Elastic arteries AKA
Conducting arteries
Tunica intima of elastic arteries
Attenuated endo
Thin/incomplete internal elastic lamina
Thicker CT
2 components of Tunica media of elastic arteries
- Thin layers of smooth muscle
2. Fenestrated sheets of elastic lamina
Tunica media of elastic arteries contains no
Fibroblasts
Outer portion of tunica media of elastic arteries
Contains vasa vasorum
Tunica adventitia of elastic arteries
Loose fibroelastic CT
Numerous Vasa vasorum
Function of vasa vasorum
Distribution of nutrients and O2
Which major luminal wall layer is thickest within elastic arteries
Tunica media
Muscular arteries AKA
Distributing arteries
Tunica intima of muscular arteries
Very thin
Tunica media of muscular arteries
Thickest/most dominant
Tunica media of muscular arteries is primarily
Smooth muscle
Tunica media of muscular arteries also contain ____ and ____ is possible
Elastic and reticular fibers, chondroitin sulfate
External elastic lamina
Tunica adventitia of muscular arteries
Fibro-elastic CT w/ sulfate GAGs and fibroblasts
Tunica adventitia of muscular arteries also contain
Vasa vasorum
Lots of sympathetics
Lots of sympathetics in tunica adventitia of muscular A help cause
Strong contraction over small area
Major luminal wall layer thickest/most dominant w/in muscular arteries
Tunica media