10-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