Blood Flashcards
a specialized connective tissue
Blood
Components of Blood
Plasma
Erythrocytes, leukocytes, platelets
Functions of blood
- delivery of nutrients and oxygen
- transport of wastes and carbon dioxide away from
cells - delivery of hormones and other regulatory substances to and from cells and tissues
- maintenance of homeostasis by acting as a buffer
and participating in coagulation and
thermoregulation - transport of humoral agents and cells of the
immune system
yellowish translucent, slightly viscous supernatant
55% at the top half of the centrifugation tube
Plasma
white or grayish thin layer between the plasma
and the hematocrit consisting of leukocytes and platelets
about 1% of the volume
Buffy coat
erythrocytes make up the bottom layer and their
volume
Hematocrit
– normally about 45% of the total blood volume in healthy
adults
Hematocrit
a yellowish liquid formed when
plasma proteins react together
Serum
– contains growth factors and other proteins
released from platelets during clot formation
Serum
Clotting in collected blood is prevented by the
addition of _________
Anticoagulants
an aqueous solution, pH 7.4, containing
substances of low or high molecular weight that make
up 8–10% of its volume
Plasma
account for approximately 7% of the
dissolved components
Plasma proteins
The composition of plasma is usually an indicator of
the mean composition of the _______
extracellular fluids in
tissues
(Major Plasma Proteins)
most abundant plasma protein
Albumin
is made in the liver and serves primarily in
maintaining the osmotic pressure of the blood
Albumin
acts as carrier protein; binding hormones, drugs,
and metabolites
Albumin
Made by liver and other cells
Alpha- and beta globulins
Include transport proteins; fibronectin; prothrombin and other coagulation factors ; lipoproteins and other proteins entering blood from tissues
Alpha- and beta globulins
Are immunoglobulins (antibodies) secreted by lymphocytes in many locations
Gamma- globulins
A system of factors important in inflammation and destruction of microorganisms
Complement proteins
The largest plasma protein (340kd), also made in the liver, which during clotting polymerizes as insoluble, cross- linked fibers which block blood loss from small vessels
Fibrinogen
Biconcave discs that lack nuclei
Erythrocytes (red blood cells)
Biconcave shape provides _________ and ______
Large surface-to-volume ratio
Facilitates gas exchange
Packed with the 02- carrying protein hemoglobin
Erythrocytes
Erythrocytes are quite flexible, which permits them to ________, assuming a _______
Adapt to the irregular bends and small diameters of capillaries
Cuplike -shape
What do erythrocytes look like in TEM?
Contents appear as dense, fine granular material
The shape of the erythrocyte is maintained by________
Two functionally significant groups of membrane proteins
Integral membrane proteins
Glycophorin C
Band 3 protein
Attaches the underlying cytoskeletal protein network to the cell membrane
Glycophorin C
Binds hemoglobin and acts as an additional anchoring site for the cytoskeletal proteins
Band 3 protein
The extra cellular domains of these proteins are glycosylated and express blood group antigens
Integral membrane proteins
Are organized into a two-dimensional lattice network that laminates the inner layer of the membrane
Peripheral membrane proteins
Peripheral membrane proteins are composed of—–
Spectrin tetramers
Actin
Band 4.1 protein
Band 4.9 protein
Adducin
Tropomyosin
Peripheral membrane proteins are anchored to the lipid bilayer by the globular protein _____, which interacts with band 4.2 proteins as well as with band 3 integral membrane protein
Ankyrin
Any defect in the expression of genes that encode the different cytoskeleton proteins can result in ————
Abnormally shaped and fragile erythrocytes
Defect in the expression of genes in erythrocytes examples
Hereditary spherocytosis
Hereditary elliptocytosis
It is caused by a primary defect spectrin in gene expression
Hereditary spherocytosis
Is caused by a deficiency in band 4.1 proteins
Hereditary elliptocytosis
Decreased number of erythrocytes in the blood
Anemia
Increased number of erythrocytes
It may be physiologic adaptation
It is associated with disease
Erythrocytosis / polycytemia
Abnormal erythrocytes with diameters >9um
Macrocytes
Abnormal erythrocytes with diameters < 6 um
Microcytes
Presence of a high percentage of erythrocytes with great variations in size
Anisocytosis
Variation in shape is called ——
Poikilocytosis
Oval, pear-shaped,teardrop-shaped,saddle-shaped,helmet- shaped, and irregularly shapedcells may be seen in a single case of
Anemia such as megaloblastic anemia
It is densely filled with hemoglobin, the tetrameric O2 - carrying protein that accounts for the cell’s uniform acidophilia
Erythrocyte cytoplasm
Hemoglobin with CO2
Carbaminohemoglobin
Combination of hemoglobin with carbon monoxide is —–
- reducing the cells’ capacity to transport O2
Irreversible
Is a pathologic condition characterized by blood concentrations of hemoglobin below normal values
Anemia
Anemia is associated with
- With a decreased number of erythrocytes
- reduced amount of hemoglobin chypchromic
Anemia causes:
- Caused by loss of blood Or hemorrhage
- insufficient production of erythrocytes by the bone marrow
- production of erythrocytes with insufficient hemoglobin
- accelerated destruction of blood cells
WBC migrate to the —– where they become functional and perform various activities
Tissues
Groups of leukocytes:
- Polymorphonuclear granulocytes
- mononuclear agranulocytes
Both types are spherical while suspended in blood plasma, but become ameboid and motile after leaving the blood vessels and invading the tissues.
Leukocytes
Two types of granules (granulocytes)
Specific granules
Azurophilic granules
Bind neutral, basic, or acidic stains
Specific granules
Specialized lysosome
Azurophilic granules (primary)
It generates hypochlorite and other reactive agents toxic to bacteria
Myeloperoxidase
Bind and produce holes in cell membranes or microorganisms
Defensins
Dissolves bacterial cell wall components
Lysozyme
Phosphates and metalloproteinases
Tertiary granules
(Neutrophils)
Percentage of circulating Leukocytes
60 - 70 %
( Neutrophils)
______ um in diameter in blood smears, with nuclei haying 2-5 lobes linked by thin nuclear extensions
12-15 um
(Neutrophils)
_____ while circulating but become______ during diapedesis upon adhering to sold substrates such as collagen in the ECM
Inactive and spherical
Actively ameboid
First leukocytes to arrive at sites of infection
Neutrophils
non-segmented nucleus of immature neutrophils that have recently entered the blood circulation
horseshoe (band forms)
An increased number of band neutrophils in
the blood indicates a higher production of
neutrophils, probably in response to a ______
bacterial infection
Neutrophils are active phagocytes that utilize a _______ to recognize bacteria
and other infectious agents at the site of
inflammation
variety of surface receptors
bind to the exposed Fc region of IgG
antibodies that coat bacterial surfaces
Fc receptors
facilitate binding and
uptake of immune complexes that are opsonized by
active C3b protein
Complement receptors (CRs)
transmembrane glycoproteins that bind to modified forms of LDLs,polyanionic molecules that are often on the surfaceof bacteria and apoptotic bodies
Scavenger receptors (SRs)
receptors that recognize pathogenic
molecules such as endotoxins, lipopolysaccharides,
peptidoglycanes, and lipoteichoic acids that are
arranged in predictable pathogen-associated
molecular patterns (PAMPs)
Toll-like receptors or pattern recognition receptors
(PRRs),
2–4% of leukocytes in
normal blood
Eosinophil
Has characteristic bilobed nucleus
Eosinophil
The main identifying
characteristic of eosinophil
the
abundance of large, red
specific granules (about 200
per cell)
increase in the number of eosinophils in blood
Eosinophilia
associated with allergic reactions and helminthic
(parasitic) infections
Eosinophilia
about 12–15 um in diameter
< 1% of blood leukocytes
Basophils
nucleus is divided into two or more irregular lobes
Basophil
has large specific granules which obscure the nucleus
Basophil
Basophils may supplement the functions of _____
Mast cells
Both basophils and mast cells have
metachromatic granules _______ bound to surface
receptors, and secrete their granular
components in response to certain antigens
containing heparin
and histamine, have IgE
Agranulocytes:
lymphocytes and monocytes
do not have specific granules, but they do
contain azurophilic granules (lysosomes)
agranulocytes
nucleus is round or indented
agranulocytes
constitute a family of
leukocytes with spherical
nuclei
lymphocytes
only type of leukocytes that
can return from the tissues
back to the blood
lymphocytes
Lymphocytes can be subdivided into
functional groups, what are they?
T lymphocytes
B lymphocytes
natural killer (NK) cells
have a long life span and are involved in
cell-mediated immunity
T cells
(T cells)
specific markers
CD4 and CD8
have variable life spans and are involved in
the production of circulating antibodies
B cells
(B cells)
specific markers
CD9
CD19
CD20
CD24
are programmed during their development to kill certain virus-infected cells
and some types of tumor cells
NK cells
NK cells specific markers
CD16
CD56
CD94
are bone marrow–derived agranulocytes with diameters varying from 12
to 20 um
monocytes
nucleus is large, off-center,
and may be oval, kidney-shaped, or distinctly U-shaped
monocytes
stains lighter than that of
large lymphocytes
monocytes
nonnucleated, disklike cell
fragments 2–4 um in diameter
Platelets
promote blood clotting
and help repair minor tears or leaks in the walls of blood vessels, preventing loss of blood
Platelets
life span of platelets
10 days
In stained blood smears,
platelets often appear in ____
clumps
Disruptions in the microvascular endothelium, which are common, allow platelet aggregation to collagen via collagen-binding protein in the platelet membrane. Thus, a platelet plug is formed as a first step to stop bleeding
Primary aggregation
Platelets in the plug release an adhesive glycoprotein and ADP, both of which are potent inducers of platelet aggregation, increasing the size of the platelet plug
Secondary aggregation
During platelet aggregation,
fibrinogen from plasma, von Willebrand factor and
others from damaged endothelium, and various
factors from platelets promote the sequential
interaction (cascade) of plasma proteins, giving rise
to a fibrin polymer that forms a three-dimensional
network of fibers trapping red blood cells and more
platelets to form a blood clot, or thrombus
Blood coagulation
other term for bloot clot
thrombus
The clot that initially bulges
into the blood vessel lumen contracts slightly
because of the interaction of platelet actin
and myosin.
Clot retraction
Protected by the clot, the vessel wall is restored by new tissue, and the clot is
then removed, mainly by the proteolytic enzyme plasmin.
Clot removal
disease due to sex-linked recessive inherited disorders.
Hemophilia
is deficient in clotting factor VIII or
contains a defective factor VIII, one of the plasma
proteins involved in fibrin generation
Hemophilia A
the defect is in factor IX
Hemophilia B
