blood Flashcards
what is blood considered to be?
Extracellular, specialized fluid connective tissue
What are the functions of blood? 7
- transporting dissolved gases: carrying O, from the lungs to tissues and returning
CO, from tissues to the lungs. - distributing nutrients absorbed from the digestive tract or released from storage in the liver or adipose tissue.
- transporting metabolic wastes from tissues to the kidney for excretion.
- distributing specific enzymes and hormones throughout the body where specific target tissues and molecules can interact with them.
- maintaining a stable pH and electrolyte composition of interstitial fluid. Blood has many buffers that resist the effect of excess metabolic acids generated by tissues (for example, lactic acid generated by skeletal muscles).
- preventing loss of fluid as a result of damaged vessels or other injuries. Clotting reactions seal breaks in vessel walls.
- carrying toxins produced by infection to the liver and kidney where they are chemically altered for excretion.
what is plasma? what does it contain? (4)
Plasma is the fluid fraction of blood, which contains many dissolved materials
-cholesterol
-plasma proteins (albumins, globulins, fibrinogen)
-metabolites (lipids, glucose, amino acids, and nitrogenous wastes)
-ions (Na+, K+, Ca2+, Mg2+, Cl-, HCO3-, HPO4 2-, SO4 2-)
what percentage of plasma does albumin comprise? What does albumin do? What ions also help play this role?
Albumin (produced by the liver) is 60% of the total volume of plasma
its function is to maintain osmotic balance by generating plasma osmotic pressure
sodium ions also generate plasma, osmotic pressure (2nd major component of plasma osmotic pressure)
What percentage of plasma do globulins make up?
globulins make up 36% of plasma. There are two classes of globulins
Transport globulins (produced in the liver) bind to less soluble molecules such as lipids, hormones, certain metallic ions (iron) and vitamins
Immunoglobulins (antibodies) are involved in the “humoral” or B-cell mediated immune response
what is the remaining 4% of plasma? (albumin 60%, globulins 36%)
clotting proteins (including fibrinogen, precursor of fibrin)
What are the three formed elements? What are they?
1) erythrocytes (red blood cell)
2) leukocytes (white blood cell)
3) platelets (cell fragments)
erythrocyte diameter? Do they contain organelles? What do they contain?
7.5 micrometers
no nucleus or organelles
they are membranous safe filled with hemoglobin
what is the role of hemoglobin?
Winding oxygen from the capillaries around alveolar sacs of the lungs and releasing it to other tissues in the body
Red blood cells also transport about 20% of the body’s carbon dioxide from the tissues, back to the lungs by binding it directly to the amino acids of hemoglobin (forming carboxyhemoglobin)
what percentage of blood are leukocytes? What is their function? How are they recruited? What are alternate ways of moving? What are the two classes of leukocytes?
White blood cells comprise less than one percent of total blood volume
The function in elaborate, non-specific and specific defense mechanisms against bacteria, virus, parasites, toxic molecules, and both dead cells and abnormal proliferating tumorigenic cells
In response to cytokines, leukocytes migrate out of capillary blood vessels (process is called diapedesis/extravasation) into extra cellular tissues or into lymphoid tissues
Some leukocytes move via pseudopod extensions and function as phagocytes
two classes of leukocytes are granulocytes and lymphocytes
what are platelets?
Platelets are cytoplasmic fragments the pinch off of megakaryocytes
Platelets contain granules with several chemicals that play a role in clotting and vascular growth
what contributes to the binding specificity of antibodies?
The unique confirmation of the portion of an antibody known as the variable region
what does ELISA stand for? What is it used for? What happens if there is fibrin in our sample?
Enzyme Linked Immunoansorbent assay
used for detection
if there is fibrin in our sample, it will be detected. By providing the appropriate chromogenic substrate for the enzyme. When the enzyme acts upon the substrate, a colored product is formed.
Enzyme will only work if the antibody is attached to the fibrin
what does anemia mean? What are the different types of anemia?
Iron-deficiency anemia occurs when there is insufficient absorption of iron in the
diet.
Pernicious anemia is another nutritionally related anemia; caused by a deficiency of vitamin B12 usually brought about by a lack of instrinsic factor synthesized in the digestive tract and required for B12 absorption.
Sickle-cell anemia arises from a mutation in the B-globin chain of hemoglobin. A base change at the level of DNA results in the insertion of the hydrophobic amino acid valine instead of the hydrophilic glutamic acid at a certain position in the polypeptide chain. The result is a hydrophobic association of the mutated B-globin molecules into long complexes that deform the erythrocyte into its characteristic “sickle” appearance. Sickled erythrocytes rupture easily and tend to clog capillaries, causing extreme pain and interference with the delivery of 02.
Polycythemia refers to an excess of erythrocytes, and may be a normal temporary response to a lack of oxygen in the blood due to heart disease or a continuous exposure to high altitudes. It may also be symptomatic of a disease of the bone marrow, in which the total volume of blood increases gradually over several years for some unknown reason. There is no known cure, but periodic phlebotomy (removal of blood) can control this condition.
what causes leukocyte disorders? What are some leukocyte disorders?
they result from insufficient overproduction of leukocytes or synthesis of abnormal leukocytes
Granulocytic leukemia involves descendants of the granulocytes, while lymphocytic leukemias involve the lymphocytes.
An acute leukemia exhibits a rapid onset and rapid progression while a chronic leukemia progresses more slowly.
Infectious mononucleosis is caused by the Epstein-Barr virus and results in an overproduction of agranulocytic leukocytes.
