HISTO CIRC AND BLOOD Flashcards
propels blood through the system and is
surrounded by the pericardium
HEART
a fibrous sac lined by
serous mesothelium.
pericardium
a series of vessels efferent from the heart that
become smaller as they branch into the various organs,
carry blood to the tissues.
Arteries
the smallest vessels, are the sites of O2 , CO2 nutrient, and waste product exchange between blood and
tissues
Capillaries
capillaries
in almost every organ form a complex network of thin,
anastomosing tubules called the _________________________
microvasculature
result from the convergence of venules into a system of larger channels which continue enlarging as they
approach the heart, toward which they carry the blood to
be pumped again.
Veins
two major divisions of arteries,
microvasculature, and veins make up the ______________________, where blood is oxygenated in the lungs, and the ___________________, where blood brings nutrients and removes
wastes in tissues throughout the body.
pulmonary circulation, systemic circulation,
thin-walled, closed-ended
tubules carrying lymph that merge to form vessels of steadily increasing size
lymphatic capillaries
The internal surface of all components of the blood and
lymphatic systems is lined by a simple squamous epithelium
called ______________
endothelium
propel
blood to the pulmonary and systemic circulations
ventricles
receive blood from the body and
the pulmonary veins, respectively
atria
consists of the lining endothelium, its supporting layer of fibroelastic connective tissue with scattered fibers of smooth muscle, and a deeper layer of connective tissue
endocardium
consists mainly of typically contractile cardiac muscle fibers arranged spirally around each
heart chamber
myocardium
Because strong force is required to pump blood through the systemic and pulmonary circulations, the _______________ is much thicker in the walls of the ventricles than the atria
myocardium
the wall of the ______________ is about ________________ than that of the right ventricle because the left side must produce sufficient force to propel blood through the much larger systemic circulation with its multiple capillary beds
left ventricle, three times thicker
is a simple squamous mesothelium
supported by a layer of loose connective tissue containing
blood vessels and nerves
epicardium
The epicardium
corresponds to the ______________________, the
membrane surrounding the heart.
visceral layer of the pericardium
These are pale-staining
fibers, larger than the adjacent contractile fibers, with sparse,
peripheral myofibrils, and much glycogen
Purkinje fibers
is a specialized epithelium that acts
as a semipermeable barrier between two major internal compartments: the blood and the interstitial tissue fluid.
endothelium
The endothelium presents a _______________________
on which blood will not clot and actively secretes agents
that control local clot formation
nonthrombogenic surface
occur in the walls of all vessels
larger than capillaries and are arranged helically in layers
Smooth muscle fibers
are found in the
subendothelial layer, between the smooth muscle layers, and
in the outer covering
Collagen fibers
consists of the endothelium and a thin subendothelial layer of loose connective tissue sometimes containing smooth muscle fibers
tunica intima
consists chiefly of
concentric layers of helically arranged smooth muscle
cells
tunica media
is connective
tissue consisting principally of type I collagen and elastic
fibers
tunica adventitia
Just as the heart wall is supplied with its own coronary
vasculature for nutrients and O2
, large vessels usually have
__________________________
vasa vasorum
are required to provide metabolites to cells in those tunics in larger vessels because the wall is
too thick to be nourished solely by diffusion from the blood in
the lumen
vasa vasorum
these include the aorta, the pulmonary artery, and their
largest branches
ELASTIC ARTERIES
are slight dilations of the bilateral internal
carotid arteries where they branch from the (elastic) common
carotid arteries
Carotid sinuses
monitoring arterial blood pressure
baroreceptors
monitor blood CO2
and O2
levels, as well as its pH
chemoreceptors
distribute blood to the organs and help regulate blood pressure
by contracting or relaxing the smooth muscle in the media
Muscular Arteries
Conduct blood
from heart and
with elastic recoil
help move blood
forward under
steady pressure
Elastic arteries
Distribute blood
to all organs and
maintain steady
blood pressure
and flow with
vasodilation and
constriction
Muscular arteries
Distribute blood
to arterioles,
adjusting flow with
vasodilation and
constriction
Small arteries
Resist and control
blood flow to
capillaries; major
determinant of
systemic blood
pressure
Arterioles
Exchange
metabolites by
diffusion to and
from cells
Capillaries
Drain capillary
beds; site of
leukocyte exit from
vasculature
Venules
Collect blood from
venules
Small veins
Carry blood to
larger veins, with
no backflow
Medium veins
Return blood to
heart
Large veins
permit and regulate metabolic exchange between
blood and surrounding tissues.
Capillaries
network of Capillaries
capillary beds
have many
tight, well-developed occluding junctions between
slightly overlapping endothelial cells, which provide for
continuity along the endothelium and well-regulated
metabolic exchange across the cells.
Continuous capillaries
This is the most
common type of capillary and is found in muscle, connective tissue, lungs, exocrine glands, and nervous tissue.
Continuous capillaries
have a sieve-like
structure that allows more extensive molecular exchange
across the endothelium
Fenestrated capillaries
permit maximal exchange of
macromolecules as well as allow easier movement of
cells between tissues and blood
Discontinuous capillaries, commonly called sinusoids
At various locations along continuous capillaries and
postcapillary venules are mesenchymal cells called
pericytes
are the primary site at which white blood cells adhere
to endothelium and leave the circulation at sites of infection
or tissue damage.
Venules
carry blood back to the heart from microvasculature
all over the body
Veins
Most veins
are classified as _____________________
small or medium veins
The big venous trunks, paired with elastic arteries close
to the heart, are the _______________
large veins
consist of thin, paired folds of the tunica intima
projecting across the lumen, rich in elastic fibers and covered
on both sides by endothelium
valves,
excess interstitial fluid from the tissue spaces
lymph
connects with the blood circulatory system near the junction of the left internal jugular vein with the left subclavian vein
thoracic duct
enters near
the confluence of the right subclavian vein and the right
internal jugular vein
right lymphatic duct
located in the subendocardial layer of both ventricles, are distinguished from contractile fibers by their greater diameter, abundant glycogen, and more sparse bundles of myofibrils
Purkinje fibers
separates
the atria from the ventricles, and provides insertions for cardiac
muscle.
cardiac
skeleton
includes the endothelium, connective tissue, and an internal elastic lamina in larger vessels;
tunica intima
contains alternating layers of smooth muscle and collagen or elastic lamellae
tunica media
contains connective tissue, small vessels
tunica adventitia
contains growth factors and
other proteins released from platelets during clot formation,
which confer biological properties very different from those
of plasma.
Serum
normally about ____ of the total blood
volume in healthy adults, is called the __________
44%, hematocrit
The straw-colored, translucent, slightly viscous supernatant comprising 55% at the top half of the centrifugation tube
is the _________________
plasma
A thin gray-white layer called the ________________________
between the plasma and the hematocrit, about 1% of the volume, consists of leukocytes and platelets, both less dense than
erythrocytes
buffy coat
is a distributing vehicle, transporting O2 , CO2 ,metabolites, hormones, and other substances to cells throughout the body
Blood
Most O2
is bound to _______________ in erythrocytes and is much more abundant in arterial than venous
blood
hemoglobin
have diverse functions and are one of the
body’s chief defenses against infection.
Leukocytes
aqueous solution containing substances of low or high molecular weight that make up
7% of its volume
Plasma
pH of Plasma
7.4
the dissolved components are mostly plasma proteins, but they
also include nutrients, respiratory gases, nitrogenous
waste products, hormones, and inorganic ions collectively
called _____________________
electrolytes
the most abundant plasma protein, is made
in the liver and serves primarily to maintain the osmotic
pressure of the blood
Albumin
made by the liver and
other cells, include transferrin and other transport factors; fibronectin; prothrombin and other coagulation
factors; lipoproteins and other proteins entering blood
from tissues
Globulins
secreted by plasma cells in many locations
Immunoglobulins
the largest plasma protein (340 kD), also made in the liver, which, during clotting, polymerizes as insoluble, cross-linked fibers of fibrin that block blood loss from small vessels.
Fibrinogen
which comprise a defensive
system important in inflammation and destruction of
microorganisms.
Complement proteins
how many % of plasma in blood
55%
plasma consists of
92% water
7% protein
1% other solutes
protein in plasma consists of
Albumins 58%
Globulins 37%
Fibrinogen 4%
Regulatory proteins <1%
how many % of RBC in blood
44%
how many % of Buddy coat in blood
<1%
Buffy Coat consists of
Platelets and Leukocytes
Leukocytes consists of
Neutrophils 50-70%
Lymphocytes 20-40%
Monocytes 2-8%
Eosinophils 1-4%
Basophils 0.5-1%
Is the solvent in which formed
elements are suspended
and proteins and solutes are
dissolved
Water (~92% of plasma)
All proteins serve to buffer
against pH changes
Plasma proteins (~7% of plasma)
Exerts osmotic force to
retain fluid within the
microvasculature
Contributes to blood’s
viscosity
Binds and transports some
fatty acids, electrolytes,
hormones, and drugs
Albumin (~58% of plasma
proteins)
transport lipids
and some metal ion
α-Globulins
transport iron ions
and lipids in bloodstream
β-Globulins
are antibodies
with various immune
functions
γ-Globulins
Participates in blood
coagulation (clotting);
precursor of fibrin
Fibrinogen
Consists of enzymes,
proenzymes, hormones, and
the complement system
Regulatory proteins
Help establish and maintain
membrane potentials,
maintain pH balance, and
regulate osmosis (control of
the percentages of water and
salt in the blood)
Electrolytes
Energy source; precursor for
synthesizing other molecules
Nutrients
terminally differentiated structures lacking nuclei and completely filled
with the O2
-carrying protein hemoglobin.
Erythrocytes
Human erythrocytes normally survive in the circulation
for about _______
120 days.
y. Leukocytes are divided into two major
groups,
granulocytes and agranulocytes,
Granulocytes possess two major types of abundant
cytoplasmic granules:
azurophilic granules
specific granules
Granulocytes also have polymorphic nuclei with two
or more distinct (almost separated) lobes and include the
neutrophils, eosinophils, and basophils
lack specific granules but do contain
some azurophilic granules
Agranulocytes
Agranulocytes include
lymphocytes and monocytes
trigger loosening of intercellular junctions in the endothelial cells of local
postcapillary venules
cytokines
Kill and phagocytose
bacteria
Neutrophils
Kill helminthic and
other parasites;
modulate local
inflammation
Eosinophils
Modulate inflammation,
release histamine during
allergy
Basophils
Effector and regulatory
cells for adaptive
immunity
Lymphocytes
Precursors of
macrophages and
other mononuclear
phagocytic cells
Monocytes
generates hypochlorite and other agents toxic to bacteria
Myeloperoxidase
degrades components of bacterial
cell walls
Lysozyme
small cysteine-rich proteins that bind and
disrupt the cell membranes of many types of bacteria
and other microorganisms
Defensins
usually the first leukocytes to arrive at
sites of infection where they actively pursue bacterial cells
using chemotaxis and remove the invaders or their debris by
phagocytosis
Neutrophils
are far less numerous than neutrophils, constituting only 1%-4% of leukocytes. increases during helminthic infections and allergic reactions
Eosinophils
The strong basophilia of the basophil granules is due to the presence of ____________ and
other sulfated GAGs.
heparin
By far the most numerous type of agranulocyte in normal
blood smears
Lymphocytes
are precursor cells of macrophages, osteoclasts,
microglia, and other cells of the mononuclear phagocyte system in connective tissue of nearly all organs
Monocytes
are very small nonnucleated, membrane-bound cell fragments only 2-4 μm in diameter.
Platelets
platelets originate by separation from the ends of cytoplasmic processes extending from giant polyploid bone marrow
cells called ______________________
megakaryocytes
the most abundant type of leukocyte, have polymorphic, multilobed nuclei, and faint pink cytoplasmic granules that
contain many factors for highly efficient phagolysosomal killing and
removal of bacteria.
Neutrophils
have bilobed nuclei and eosinophilic-specific granules
containing factors for destruction of helminthic parasites and for
modulating inflammation
Eosinophils
the rarest type of circulating leukocyte, have irregular
bilobed nuclei and resemble mast cells with strongly basophilicspecific granules containing factors important in allergies and
chronic inflammatory conditions, including histamine, heparin,
chemokines, and various hydrolases
Basophils
agranulocytes with many functions as T- and B-cell
subtypes in the immune system, range widely in size, depending on
their activation state, and have roughly spherical nuclei with little
cytoplasm and few organelles
Lymphocytes,
are larger agranulocytes with distinctly indented or
C-shaped nuclei, which circulate as precursors of macrophages and
other cells of the mononuclear phagocyte system
■ Monocytes
are small (2-4 μm) cell fragments derived from megakaryocytes in bone marrow, with a marginal bundle of actin filaments,
alpha granules and delta granules, and an open canalicular system
of membranous vesicles; rapid degranulation on contact with collagen triggers blood clotting
Platelets
