Cardiovascular System (quiz 3) Flashcards
The main function of blood vessels is to transport blood and control flow/diameter. What does this mean and how is it done?
-changes BP to regulate blood flow
-smaller diameter= less blood flow
-larger diameter= more blood flow
-blood flow is controlled by the ANS
Does blood follow a pressure gradient?
yes! happens mostly in small vessels and blood will only go from high pressure to low pressure
What texture is the lining in blood vessels?
smooth
Walls of both arteries and veins have 3 tunics. What are they?
tunica intima, tunica media, tunica externa (also called adventitia)
The innermost tunica, tunica intima consists of the endothelium (simple squamous epithelia) and a thin sub-endothelial layer of _______________ tissue (sometimes containing smooth muscle fibers)
loose CT
In arteries, the tunica intima includes a thin layer, the ______________________, composed of elastin
internal elastic lamina (near basal lamina)
The tunica media, the middle layer, consists chiefly of concentric layers of helically arranged _______________ cells. In arteries, the media may also have an external elastic lamina separating it from the outermost tunica
smooth muscle
The outer adventitia, or tunica externa, is connective tissue consisting principally of….
type I collagen fibers and elastic fibers (allow tunica externa to recoil/distend)
The adventitia/tunica externa is ______________ with and bound to the stroma of the organs through which the blood vessel runs
continuous
Large vessels usually have vasa vasorum (“vessels of the vessel”): ____________, _________________, and ____________ in the adventitia/tunica externa and outer part of the tunia media. Blood in the lumen does not supply the tunics alone. The adventitia of larger vessels also contains a network of unmyelinated autonomic nerve fibers
arterioles, capillaries, venules
The aorta is what type of artery?
elastic artery
List the arteries, capillaries, and veins in order of flow
-elastic a. (aorta)
-muscular a.
-arteriole
-continuous capillary
-fenestrated capillary
-venule
-mid-sized and large sized vein
Which artery branches off of elastic artery?
muscular artery
What tissue is the muscular artery made up of?
smooth muscle
What is another name for the muscular arteries?
distribution arteries (helps distribute blood)
What is the arteriole missing compared to other blood vessels?
missing the outer tunica layer- tunica externa
Which blood vessel is the “first within the target”?
the arteriole (found within femur, kidney, deltoid, tibia, etc)
What are the smallest blood vessels?
capillaries (this is why they exist in capillary beds, so theres multiple little ones near each other)
What is feeding and draining the capillary beds?
1 artery feeds cap bed, 1 vein drains it
What are the exchange vessels working with concentration gradients?
capillaries
The capillaries contain endothelial cells, which means it is made of up ___________________ tissue
simple squamous
Where do fenestrated capillaries drain into?
the smallest vein vessel, aka the venule
Who is the first to receive blood from capillaries?
venules
What is the venule missing compared to other blood vessels?
missing the tunica media (smooth muscle layer)
What blood vessels unite/fuse with neighbors?
venules> mid-size veins> large size veins
What do blood vessels require to constrict/dilate?
tunica media
So:
-arteries can constrict/dilate
-arteriole can
-capillaries cannot
-venule cannot
-veins can
Elastic arteries are the aorta, ___________________, and their largest branches.
pulmonary artery
What is another name for elastic arteries?
conducting arteries (bc their major role is to carry blood to smaller arteries)
Elastic arteries have a _________ tunica media in which elastic lamellae alternate with layers of smooth muscle fibers. Between the tunica intima and the tunica media is the ___________________
thick, internal elastic lamina
____________ arteries, also called distributing arteries, distribute blood to the organs and help regulate blood pressure by contracting or relaxing smooth muscle in the tunica media
Muscular
In muscular arteries, the tunica media may contain up to _____ layers of large smooth muscle cells interspersed with a variable number of elastic lamellae. The external CT contains lymphatic capillaries, vasa vasorum, and nerves, all of which may penetrate to the outer part of the ______________
40, tunica media
With distance from the heart, arteries gradually have relatively less __________ and more ________________ in their walls
elastin, smooth muscle
Most arteries, large enough to have names are of the ______________ type
muscular
Muscular arteries are _____________ arteries
efferent (away from heart)
Muscular arteries branch repeatedly into smaller and smaller arteries, until reaching a size with 3/4 layers of _________________ muscle.
medial smooth
The smallest arteries branch as….
arterioles
How many layers do arterioles have of smooth muscle?
1-2 layers (has no external layer, are very thin)
What blood vessel is the beginning of an organs microvasculature?
arterioles
Arterioles branch to form anastomosing networks of capillaries that surround the ________________ cells of the organ
parenchymal
At the ends of arteries, smooth muscle fibers act as sphincters (________________) and produce periodic blood flow into capillaries
pre-capillary sphincter
Capillary beds are supplied by _____________ and drain into ____________
arterioles, venules
What does red represent?
oxygenated blood
What does blue represent?
de-oxygenated blood
Do capillaries exchange in both directions?
yes!
The right and left ventricles propel blood to the ______________ and _______________ circuits
pulmonary and systemic
What part of the heart receives blood?
right and left atria
The walls of all 4 heart chambers consist of 3 major layers. What are they?
1) internal endocardium
2) middle myocardium (cardiac muscle layer, not uniform- varying thickness (LV is thickest))
3) external epicardium (2 layers that form cavity for heart to sit in, same as viscera)
How much muscle you have in the heart depends on what?
how much pressure you have to generate
LV has the thickest muscle
RV is second thickest
atriums are thinner
What is the endocardium lined with?
endothelium (simple squamous epithelia)
What does the endocardium consist of?
-endothelium lining (simple squamous)
-supporting layer of fibroelastic CT w/ scattered fibers of smooth muscle
-a deeper layer of CT (continuous w/ that of the myocardium and often called the sub-endocardial layer)
-modified cardiac muscle fibers that are the conducting system
The myocardium consists mainly of typically contractile cardiac muscle fibers arranged spirally around each heart chamber. The myocardium is much thicker in the wall of the _______________ than the _____________
ventricles, atria
The epicardium is a simple squamous _________________ supported by a layer of loose CT containing blood vessels and nerves
mesothelium
The epicardium corresponds to the ____________ layer of the ________________, the membrane surrounding the heart
visceral, pericardium
During heart movements, underlying structures are cushioned by deposits of _____________ tissue in the epicardium
adipose
Friction within the pericardium is prevented by lubricant fluid produced by both layers of serous mesothelial cells. What is this fluid called?
pericardial fluid
In both the sub-endocardial layer and the adjacent myocardium, modified cardiac muscle cells make up the _____________________ system of the heart
impulse conducting
The conducting cells of the heart are specialized to do what?
to generate and conduct waves of depolarization
this stimulates rhythmic contractions in adjacent myocardial fibers
The system consists of 2 nodes of specialized myocardial tissue in the R atrial wall- the sinoatrial (SA) node, or pacemaker) and the atrioventricular (AV) node, from which the AV bundle emerges
Blood does not have protein fibers, just proteins. Why?
otherwise it would be too viscous
this is bad because blood is a FLUID CT
What are the specialized cells of blood called? What is the fluid matrix called?
formed elements, plasma
What are the specific types of leukocytes?
-neutrophils
-eosinophils
-monocytes
-lymphocytes
-basophils
A tube of blood after centrifugation has nearly half of its volume represented by erythrocytes in the bottom half of the tube, a volume called the….
hematocrit
A tube of blood after centrifugation has nearly half of its volume represented by erythrocytes in the bottom half of the tube, a volume called the hematocrit. Between the sedimented erythrocytes and the supernatant light-colored plasma is a thin layer of leukocytes and platelets called the….
buffy coat
The straw-colored, translucent, slightly viscous supernatant comprising 55% at the top half of the centrifugation tube is the plasma. Plasma is an aqueous solution containing substances of low or high molecular weight. What plasmas pH?
7.4 (the average is 7.35)
if plasma is higher than 7.4 or lower than 7.35 this is bad!!!
The straw-colored, translucent, slightly viscous supernatant comprising 55% at the top half of the centrifugation tube is the plasma. The dissolved components are mostly plasma proteins, but also include nutrients, respiratory gases, nitrogenous waste products, hormones, and inorganic ions collectively called….
electrolytes
Which plasma protein is trapped in the blood vessels?
albumin
What is the most abundant plasma protein?
albumin
Where are all plasma proteins made besides immunoglobulins and complement proteins?
the liver
What is the function of albumin (a plasma protein)?
maintain the osmotic pressure of the blood
What are the other names of globulins (a plasma protein)?
alpha and beta globulins
What are the specific globulins (plasma protein) we discussed in class?
-transferrin
-fibronectin
-prothrombin
-coagulation factors
What does transferrin (a globulin/plasma protein) do?
transports iron around the body
What are the other names for immunoglobulins?
antibodies or y-globulins
Who secretes immunoglobulins?
plasma cells (leukocytes)
What is the largest plasma protein?
fibrinogen
Is fibrinogen soluble or insoluble?
soluble
What does fibrinogen (a plasma protein) do?
during clotting, fibrinogen polymerizes into insoluble fibrin
What do complement proteins (plasma proteins) do?
comprise a defensive system important in inflammation and destruction of microorganisms
What part of the blood can be studied histologically in smears prepared by spreading a drop of blood in a thin layer on a microscopic slide?
Note: the blood smears are routinely stained with mixtures of acidic (eosin) and basic (methylene blue) dyes
formed elements (erythrocytes and leukocytes)
What blood cells DO NOT divide, repair themselves, or do not do protein synthesis?
erythrocytes
Erythrocytes are terminally differentiated structures lacking nuclei and are completely filled with the oxygen carrying protein _____________
hemoglobin
What blood cells are the only ones that do not leave blood vessels?
RBCs
RBCs are flexible biconcave disces. What is the purpose of this?
for flexibility and SA, will help get through small BV
What are stacked RBCs called?
rouleaux
What blood cells can migrate from blood vessels to tissues?
WBCs
What are the 2 categories of leukocytes?
granulocytes and agranulocytes (based on the density of their cytoplasmic granules)
WBCs are spherical while suspended in blood plasma but they become ____________ and _________ after leaving the blood vessels and invading the tissues
amoeboid, motile
Which leukocytes are the first ones to show up to an inflammation site or infection?
neutrophils
Which leukocytes are the most numerous?
neutrophils (and numerous nuclei!)
Are neutrophils specific or nonspecific?
nonspecific
What do neutrophils do?
phagocytosis
What do eosinophils do?
destroy extracellular pathogens- best known for parasites/helminth
Which leukocyte stains red?
eosinophil
Which leukocyte stains dark purple/black?
basophil
Which leukocyte is less than 1% of blood (least numerous)?
basophil
Which leukocytes can do widespread effects within local tissues?
basophil
Which leukocyte is massive?
monocyte (also, “m” for munching like a pacman)
Which leukocyte hides in CT?
lymphocyte
Which leukocyte is little and appears like its just the nucleus present, with very little cytoplasm?
lymphocytes
What are the 2 types of lymphocytes (a leukocyte)?
B cells and T cells
Which leukocyte is specific?
lymphocytes (B and T cells)
Which leukocytes are granulocytes?
-eosinophil
-neutrophil
-basophil
Which leukocytes are agranulocytes?
-lymphocytes
-monocytes
Which blood cells function in gas exchange?
RBCs
Anemia is the condition of having a concentration of erythrocytes ________ the normal range. With fewer RBCs, tissues are unable to recieve adequate __________
below, oxygen
What are the symptoms of anemia?
-lethargy
-SOB
-fatigue
-skin pallor
-heart palpation
Sickle cell anemia is caused by a homozygous mutation causing _____ amino acid substitution in a hemoglobin, which renders the mature RBCs deformed and slightly rigid (hemoglobin not folded properly)
an (1)
(this will starve distal tissues of oxygen, the blood cells can get stuck and will cause symptoms of pain)
What is polycythemia?
-increased concentration of RBCs in blood (too many/thick RBCs)
-elevated hematocrit increases blood viscosity, putting strain on heart
polycythemia is a physiologic adaptation for who?
individuals who live at high altitudes where oxygen tension is low
also athletes go to high altitude before a big game or tournament to increase their RBCs naturally to perform better
What is the RBC protein that helps make RBCs?
erythropoietin (EPO)
Blood platelets (or thrombocytes) are very small non-nucleated, membrane-bound cell fragments that are formed by….
megakaryocytes (from HSCs)
Platelets promote blood clotting and help repair minor tears or leaks in the walls of small blood vessels, preventing loss of blood from the microvasculature. How are they able to accomplish this?
by sticking really well
What is the lifespan of platelets?
10 days
Where do platelets hide until needed?
in the spleen
