Circulatory Cells Flashcards
True or false; the circulatory system consists of the cardiovascular system and lymphatic system
true; (Broken into 3 parts heart, blood vessels, and lymphatic vessels)
Is the endocardium of the heart thick or thin?
fairly thin
How many layers does the endocardium of the heart have? What are their names?
4: Endothelium, Looser Ct. layer & Dense regular Ct. layer (together make sub-endothelium), Sub-endocardial layer
The endothelium of the endocardium is made of what kind of cells
simple squamous
The looser Ct. layer of the endocardium is made of what kind of Ct.?
fibroelastic Ct.
The dense regular Ct. layer of the endocardium is composed of what 3 things?
Collagen 1, elastic fibers, some smooth muscle
True or false; most of the sub-endocardial layer of the endocardium is purkinje fibers (specialized cardiac myocytes)
true
Would you find blood vessels and nerves in the sub-endocardial layer of the endocardium?
yes
What is the function of the purkinje fibers in the sub-endothelial layer of the endocardium
transmit contraction impulse rapidly (attached via gap junctions)
True or false; the ventricle of the myocardium has less cardiac muscle then atria and is full of elastic fibers
false; other way around
What would you find in the longitudinal portion of an intercalated disc?
Large gap junctions (massive ion flow)
True or false; the transverse portion of an intercalated disc has macula adherents (desmosomes), fascia adherents, and small gap junctions
true
What are the 3 functions of intercalated discs
Cell to cell communication (ion flow-longitudinal portion)
Attach cardiac muscle
Stabilize myofibrils
What is the function of the specialized cardiac muscle cells Myoendocrine cells? What is the target organ they are influencing?
Function: secrete hormones into surrounding capillaries
target: Kidneys (fluid and electrolyte balance) or Small artery (relax tunica media to decrease BP)
What produces the serous fluid that accumulates in the pericardial cavity
Serous pericardium
True or false; the epicardium = visceral pericardium
true
The Epicardium or Visceral pericardium contains a sub-epicardial layer of fibroelastic Ct. containing what?
Coronary vessels
Nerves
and sometimes adipose tissue - (adds stress to heart beat)
What secretes a serous lubricating fluid in the Epicardium or Visceral pericardium
The mesothelium
What are the 2 parts of the Serous Pericardium
Epicardium and Partietal pericardium
True or false; the Parietal pericardium contains a mesothelium (secreting serous fluid) and a layer of fibroelastic Ct.
true
What two components make up the pericardial sac
Parietal pericardium and fibrous pericardium
What kind of collagen primarily makes up the fibrous pericardium
type 1
What makes up the boarders of the pericardial cavity? And how much fluid can it hold
Between Parietal pericardium and Epicardium (Visceral Pericardium)
Can hold ~15-50 mL
True or false; Dense irregular ct. has many collagen 1 and elastic fibers and is almost always Avascular
true
What kind of ct. makes up the cardiac skeleton
dense irregular ct.
True or false; the tunica media of muscular arteries is primarily composed of smooth muscle and richly innervated by SNS
true
What is the smallest of artery types
arterioles
True or false; both muscular arteries and arterioles contain a thin tunica intima, thick tunica media, and fibroelastic tunica adventitia
true
What happens to the number of elastic laminae in elastic arteries as you age?
increases
What happens to muscular arteries as you age?
Collagen 1 and proteoglycans increase after middle age
resulting in decrease in flexibility (coronary vessels greatly affected)
Hypertension (increase in systolic BP) can occur around middle age which causes what in arteries
elastic fibers decrease and are replaced by collagen 1 (adds stiffness)
True or false; atherosclerosis typically occurs in the smallest of arteries
false; typically in largest
What blood vessels are the “over flow prevention system”
Metarterioles
What blood vessels are the “by-pass system”
AVA = arteriovenous anastomosis = AV shunt (richly innervated)
What happens if an AVA (AV shunt) is closed? What about open?
Closed - blood into capillary bed
Open - blood diverted from capillary bed
True or false; Metarterioles, AVA’s, Pre-capillary sphincters, and size of terminal arteriole lumen are all functions determining blood flow into capillaries
true
What is the most common capillary type?
Continuous capillaries
What kind of capillaries would you find in pancreas, intestines, or endocrine organs
fenestrated capillaries
What kind of capillaries would you find in bone marrow, liver, spleen, lymphatic organs, and some endocrine organs
sinusoidal capillaries
How are veins similar to arteries in structure? How do they differ?
Similar - have 3 tunicas
Different- not as uniform (no smooth muscle) - often larger lumen
True or false; valves of veins are strong and thick
false; thin and delicate
Do venules of veins play a role in inflammation?
yes; incomplete tunica media allows products of inflammation through to loosen endothelial cell junctions
What are 2 major differences between continuous blood capillaries and lymphatic vessels
Lymphatics are blind ended and no pericytes
True or false; pericytes are numerous on capillaries and venules
true
What is major function of pericytes
healing
