Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
30 Cards in this Set
- Front
- Back
|
What is the fxn of the circulatory system?
|
-Perfuse all the cells and tissues of the body
---deliver nutrients and oxygen ---remove wastes including CO2 -Communitcation - delivers hormones (endocrine) -Thermoregulation |
|
|
What are the components of the circulatory system?
|
-Heart
-Vasculature ---blood vessels - arteries, capillaries, veins, (complete circuit) ---Lymphatics - from periphery to central vein |
|
|
What tissues comprise the cardiovascular system?
|
-cardiac and smooth muscle
-epithelium -connective tissue |
|
|
What are the blood vascular components?
|
-arteries
-capillaries -veins |
|
|
What are the lymph vascular components?
|
-capillaries
-lymphatic vessels -lymph nodes |
|
|
What are the basic layers of the blood-vascular system?
|
-tunica intima - innermost layer
-tunica media - middle layer -tunica adventitia - outermost layer |
|
|
What is the tunica intima comprised of and where is it located?
|
-endothelium and delicate collagenous tissue
-occasional myointimal cells (type of smooth muscle that express hematopoietic lineage markers) -innermost layer adjacent to the lumen |
|
|
What is the tunica media comprised of and where is it located?
|
-smooth muscle
-elastic lamina - varies in thickness greatly -middle layer |
|
|
What is the tunica adventitia comprised of and where is it located?
|
-connective tissue
-Vasa vasorum (in larger vessels) - small vessels that supply the walls of larger vessels ---means vessels of vessels in latin |
|
|
What are the 3 tunicas called in the heart?
|
Endocardium (tunica intima) - endothelium and connective tissue
Myocardium (tunica media) - cardiac muscle Epicardium (tunica adventitia) - adventitia plus visceral pericardial sac |
|
|
Where is the Vasa Vasorum highly developed?
|
The coronary vasculature
|
|
|
Where is the Myocardium the thickest in the heart?
|
-Left ventricle
-right ventricle -right atrium ? -left atrium ? |
|
|
What is the pathway for the conducting system of the heart?
|
Sinuatrial (SA) node --> internodal pathway --> transitional fibers --> Atrioventricular (AV) node --> penetrating fibers --> distal fibers --> Bundle of His (AV bundle) --> R&L bundle branches --> endocardium at Apex --> Purkinje fibers --> ventricular myocardium
|
|
|
In what order do the atria and ventricles contract?
|
-Right and Left Atria together
-Left Ventricle -Right Ventricle |
|
|
After the electrical signal leaves the Bundle of His, what keeps the signal from crossing between the ventricles and contracting simultaneously?
|
the Interventricular septum
|
|
|
What do the papillary muscles do, how many are there, where are they located, and to what do they attach?
|
They keep the Mitral/Bicuspid and Tricuspid valves closed during ventricular contraction to prevent back-flow
-3 in right ventricle - anterior, posterior, and septal papillary muscles ---attach via chordae tendineae to the tricuspid valve -2 in left ventricle - anterior and posterior papillary muscles ---attach via chordae tendineae to the mitral/bicuspid valve |
|
|
What do the electrical signals cause to contract?
|
Myocardium layer
|
|
|
What is the Septomarginal trabecula (moderator band), and where is it located?
|
-it carries part of the right bundle branch of the AV bundle of the conduction system of the heart to the anterior papillary muscle. This shortcut across the chamber of the ventricle seems to facilitate conduction time, allowing coordinated contraction of the anterior papillary muscle
-Right ventricle - frequently extends from the base of the anterior papillary muscle to the ventricular septum -Called moderator band because it was thought to prevent overdistension of the right ventricle |
|
|
What is the sulcus terminalis and why is it important?
|
-an external sulcus that extends from front of the Inferior to Superior Vena Cavas
-Its superior border marks where the Sinuatrial (SA) node is in the Right Atrium |
|
|
What tissue comprises the electrical conducting system of the heart?
|
Modified cardiac muscle
|
|
|
What are the Sinoatrial and Atrioventricular nodes made of, how are they excited, and what surrounds them?
|
-small fibers, little contractile protein and glycogen
-Spontaneous excitation -surrounding dense connective tissue has abundant autonomic nerve endings |
|
|
Where are the Purkinje fibers located?
|
Subendocardial before penetrating the myocardium
|
|
|
What are the histological features of Purkinje fibers?
|
-larger than usual myocardial cells
-pale cytoplasm w/ large amounts of glycogen and mitochondria -few myofibrils arranged irregularly -Lack T-tubule system -Intracellular cxns are GAP JXNS and DESMOSOMES -Nuclei are large and round |
|
|
What are the Heart valves made of?
|
Collagenous tissue covered by endocardium
-lamina fibrosa is central dense sheet -Elastic fibers in subendothelial tissue |
|
|
Are the heart valves vascular or avascular?
|
Avascular
|
|
|
What supports the Heart valves?
|
Fibrous skeleton of the heart
|
|
|
What electrically isolates the atria from the ventricles?
|
the fibrous skeleton of the heart
-also surrounds the vessels of the 4 valves of the heart |
|
|
What are the valves of the heart starting with blood entering the right atrium from the Vena Cava? (4)
|
-Tricuspid Valve - right atrium to right ventricle
-Pulmonary Semilunar valve - right ventricle to pulmonary arteries -Mitral/Bicuspid valve - left atrium to left ventricle -Aortic Semilunar valve - Left ventricle to aorta |
|
|
What are the cusps of the valves and how many are there?
|
They serve to seal the heart valves when closed
-there are 3 cusps per valve except the Mitral - it has only 2 ---that's why it's also called the Bicuspid valve |
|
|
What connects the 4 valves together?
|
the fibrous skeleton of the heart, specifically - Left and Right fibrous trigones and the tendon of the conus
|
