Chapter 7: circulatory system (Heart) (exam 2) Flashcards
the circulatory system consists of what two systems?
the cardiovascular system to carry blood and the lymphatic system to collect and transport lymph
what are the layers of the heart
Endocardium, myocardium, pericardium, pericardial sac, pericardial cavity, general valve, cardiac skeleton
Endocardium has what type of endothelium?
simple squamous one layer thick
what type of loose connective tissue is found in the endocardium?
fibroelastic ct
in the more dense regular ct layer what typed of fibers are found?
more collagen I and elastic fibers as well as some smooth muscle
The sub endocardial layer is composed of what?
looser CT with blood vessels, nerves and purkinje fibers
in the heart purkinje fibers are modified what?
cardiac myocytes
in the sub-endocardial layer where are myofibrils found?
in the peripheral and are few in numbers
what is stored in the sub endocardial layer
glycogen
the sub-endocardial layer is attached to the endocardium via what?
Gap-junctions
what is the function of a sub-endocardial layer?
to transmit contraction impulse rapidly
What layer is the atria and ventricle found in
Myocardium
compared to the ventricle, the atria has more what and less what?
has more elastic fibers and more muscles
the ventricle, compared to the atria, has a well developed what?
well developed muscular layer
The intercalated disc is found in which layer
in the myocardium
what are the two portions of the intercalated disc structure?
longitudinal portion and transverse portion
What is found in the transverse portion of the myocardium
macula adherens (desmosomes)
fascia adherens
small gap junctions
what is found in the longitudinal portion
large gap junction for movement
What is the function of the myocardium
- attach cardiac myocytes in a row
- attach and stabilize myofibrils (actin/myosin)
- cell to cell communication
What will sympathetics do to the heart rate and contraction
heart rate will increase and contraction will increases
what will parasympathetics do to the heart rate and contraction?
they will both decrease
Specialized cardiac muscle cells are known as
myoendocrine cells
Myoendocrine cells will secrete hormones in what region
in the atria
were will hormones be released into
surrounding capillaries
what is the function of hormones secreted by myoendocrine cells
to influence fluid and electrolytes balance
influence in decreasing BP
when influencing the fluid balance what is the target organ
kidney
when influencing the decrease in blood pressure what is the target?
small arteries and arterioles
The pericardium is also known as what
serous pericardium
what are the two layers of the pericardium
epicardium (visceral pericardium) and parietal pericardium
what are the two layers in the epicardium
sub-epicardium and mesothelium
the sub-epicardium is a layer of what CT
fibroelastic CT
the sub-epicardium contains what
coronary vessels, nerves, and sometimes lots of adipose
what is secreted from the mesothelium layer
secretes serous lubricating fluid
the parietal pericardium is composed of what?
mesothelium and a layer of fibroelastic ct
the pericardial sac is composed of what two layers
fibrous and parietal pericardium
The pericardial cavity holds how much fluid
30-50 ml
the pericardial sac is between what two layers
visceral pericardium and parietal pericardium
Valves are composed of what tissue
endothelium with dense irregular CT
the Dense irregular CT of valves have many what
collagen I and elastic fibers
are the valves of the heart vascular or avascular
almost avascular
what is the cardiac skeleton made out of
dense fibrous CT
What are the three main components of the cardiac skeleton
annuli fibrosi
trigonum fibrosum
septum membranaceum
the annuli fibrous is found around what?
the base of the aorta, pulmonary artery and the opening to the chambers
the trigonum fibrous is found by what
by cusps of aortic valve
the septum membranaceum is found where
upper portion of inter ventricular septum
the function of the septum membranaceum is what
1) support
2) origin/insertion for cardiac monocytes
chordae Tendinae are tendon-like so therefore the CT type is what?
dense regular
