Unit 4 Flashcards
What are the Major layers of the heart
Endocardium
Myocardium
Pericardium
What are the layers of the Endocardium
Endothelium
Subendothelial layer
Subendocardial layer
What type of Tissue makes up the Endothelium
Simple Squamous
What tissues make up the Sub Endothelial layer of the endocardium
Loose Ct = Fibroelastic Dense Irregular (collagen 1 + elastic + smooth muscle)
What special fibers are found in the subendocardial layer
Purkinjefibers
Why are myofibrils in purkinje fibers peripherally placed
Because of the glycogen in the purkinje fibers displace the myofibrils
What attaches Purkinje fibers together
Gap junctions and Macula adherens
What is different in the fiber composition in the atrial myocardium vs the ventricle
Atria = more elastic fibers Ventricle = Lots of muscles
What is found on the transverse portion of intercalated discs
Macula adherens
Fascia adherens
What is found on the longitudinal portion of intercalated discs
Large gap junctions
What are the functions of Intercalated discs
Attach cardiac myocytes
Stabilize myofibrils
Cell to cell communication
What part of the intercalated discs attach cardiac myocytes together
Macula adherens
What part of the intercalated discs stabilize myofibrils
Fascia adherens
What part of the intercalated discs provide cell to cell communication
Large gap junctions
What does SNS activation of cardiac muscles do
Increase HR
Increase contraction force
What does Para symp activation of cardiac muscle do
Slow HR
Decrease contraction force
What specialized cells in the atria and septum of the heart release hormones
Myoendocrine cells
What is the function of the Myoendocrine
Fluid and electrolyte balance
Decrease BP
What layer of the heart are myoendocrine cells found
Myocardium
What are the two parts of the pericardium
Serous Pericardium
Parietal pericardoum
What are the two parts of the Serous or parietal pericardium
Epicardium
Mesothelium
What make up with Sub-epicardial layer of the epicardium
Coronary vessels
Nerves
Adipose
What does the mesothelium of the percardium do
Secrete a serous lubricating fluid
What makes the parietal pericardium so strong
It is a layer of fibroelastic CT
How much fluid is in the pericardial sac
15-50ml
What are heart valves made up of
Endothelium with dense irregular Ct below
What type of fibers make up the dense irregular CT of a heart valve
Collagen 1 and elastic fibers
What is the cardiac skeleton
High density CT layer of the heart that forms and anchors valves
What is the cardiac skeleton made up of
Dense irregular CT
What are the three main components of the Cardiac skeleton
Annuli fibrosi
Trigonum fibrosum
Septum membranaceum
Where is the annuli fibrosi
the base of aorta and pulmonary artery
Where is the trigonum fibrosum
Cusps of aortic valve
Where is the septum membranaceum
Upper portion of the interventricular septum
What is the function of the septum membranaceum
Provide an origin and insertion for cardiac monocytes
What type of CT are chordae tendinae
Dense regular
What is the function of the Cardiac Skeleton
Ensure individual chamber contractions
What is chest pain brought on by exertion
Angina
What causes angina
Progressive narrowing or coronary vessels = Less O2
What is an abnormal heart rhythem
Dysrthmia
What Blood vessel layer is a continuation of the Endocardium of the heart
Tunica intima
What blood vessel layer is continuation of the Myocardium of the heart
Tunica media
What blood vessel layer is a continuation of the Epicardium of the heart
Tunica Adventitia
What are elastic arteries also called
Conducting arteries
What are examples of conducting arteries (elastic arteries)
Aorta
Common iliacs
Carotid
Subclavian
What is the most dominant layer in an artery
Tunica Media
What layer of elastic arteries has fenestrated sheets of elastic fibers
Tunica media
What layer of arteries contain numerous Vasa Vasorum
Tunica adventicia
What are vasa vasorum
Small blood vessels supplying large blood vessels
What is the tunica intima mainly made up of
Thick connective tissue with collagen 1 fibers
What is another name for muscular arteries
Distributing arteries
What layer is the largest in arteries
Tunica media
What layer within the tunica intima of muscular arteries is well developed
Internal elastic lamina
What type of tissue makes up the tunica intima
Endothelium
What type of muscle is found in the tunica media of muscular arteries
Circular smooth muscle
What type of tissue makes up most of the tunica adventicia of arteries
Fibrous Connective tissue
Arteriole structure is similar to muscular artery structure except for
Arterioles do not have elastic laminae
What layer of the artery is most likely to be affected by atherosclerosis
Tunica intima
What layer is missing in metaarterioles
Tunica media
What controls blood flow into true capillaries
Pre-Capillary sphincters
Where can you find Ateriovenous anastomosis (AV shunts)
SKin
Stomach
Erectile tissue
What influences capillary flow
Metarterioles
Shunts
Lumen size
Precapillary sphincters
What is the function of pinocytotic vesicles in capillaries
Restricts diffusion of large M/C
What is the function of Fasciae occludens in capillaries
Move macromolecules
Allow cell movement
What are the three types of capillaries
Continuous
Fenestrated
Sinusoidal
What is the most common type of capillary
Continuous
What type of capillaries contain pericytes
Continuous
What replaces Fasciae Occludens in CNS capillaries
Zonula occludens
What is thee function of Pericytes
Healing
Regulate Blood flow
Where are Fenestrated Capillaries located
Pancreas
Intestines
Endocrine organs
Kidneys
What type of capillaries have thin protein diaphragms
Fenestrated Capillaries
What is the function of Fenestrated capillaries
Allow greater movement of molecules in cells
Where are sinusoidal capillaries located
Bone marrow
Liver
Spleen
Lymphatics
What is different between fenestrated capillaries and sinusoidal capillaries
Sinusoidal capillaries have holes (fenestration) but no diaphragm
What type of capillaries have the greatest exchange between blood and tissues
Sinudoidal capillaries
What are valves in veins made up of
Two flaps of tunica intima and fibroelastic tissue
What is the function of a valve in a vein
Prevent backflow
What keeps blood moving in veins
Skeletal muscles
What layers are in postcapillary venules
Tunica intima
Collecting venules contain what luminal wall layers
Tunica intima
Tunica adventitia
What veins contain all three luminal wall layers
Muscular venules
What veins have the most pericytes
Postcapillary veins
What veins have the least amount of pericytes
Muscular veins
What is the structure of small veins
Similar to venules except they have a complete tunica media
What veins contain numerous vavles
Medium veins
What layer is the thickest in medium veins
Tunica adventitia
What is different in the tunica intima between large veins and medium veins
Large veins have a thicker CT layer in the tunica intima
Which luminal wall layer is well developed in superficial veins of the legs
Tunica media
Which luminal wall layer is well developed in pulmonary veins
Tunica media
What veins contain some cardiac muscle in the tunica adventitia
Pulmonary
Superior and inferior vena cava
What is the function of Lymphatic vessels
Drain excess fluid
Transport lymph to nodes
Transport lymph to blood stream
Do lymphatic capillaries have paeicytes
no
Do lymphatic capillary endothelial cells have tight junctions
no
DO lymphatic capillary endothelial cells have anchoring filaments
yes
What luminal wall layers to medium and large lymphatic vessels contain
All three
What component of lymphatic vessels support endothelia walls so capillaries stay open
Anchoring filaments
what allows movement across lymphatic vessels
Clefts formed by overlapping endothelial cells
What redicects blood away from capillary beds
AVA shunts
What structure in the tunica adventitia supplies cells with the materials they need to survive
Vasa vasorum
What is associated with vessels called thoroughfare channels
Metarterioles
What is the tunica media of Elastic arteries mainly made up of
Fenestrated elastic laminae
What is the tunica media of muscular arteries mainly made up of
Smooth muscle