Lecture 9 Unit 2 Flashcards
what 2 fluids are the cells of the body serviced by?
-blood
and interstitial fluid
how do nutrients and oxygen diffuse?
from the blood into the interstitial fluid and then into the cells
how do wastes move?
in the reverse direction
what is hematology?
the study of blood and blood disorders
what 2 things is blood composed of?
plasma and formed elements
what is plasma?
a clear straw colored watery liquid that consists of 91.5% of water and 8.5% solutes
what are formed elements?
cells and cell fragments
where are the plasma proteins in the blood plasma made?
the liver
where are plasma proteins confined to?
bloodstream
what is in plasma?
albumins globulins and fibrinogen
what do albumins do?
maintain blood osmotic pressure
what is in globulins?
- antibodies which bind to foreign substances called antigens
- form antigen antibody complexes
what does fibrinogen do?
clotting purposes and contains blood serum
what is blood serum?
plasma without fibrinogen and other clotting factors
what is another name for red blood cells?
erythrocytes or RBCs
what is another name for white blood cells?
leukocytes or WBCs
what are the two types of white blood cells?
- granular leukocytes
- agranular leukocytes
what are the types of granular leukocytes?
- neutrophils
- eosinophils
- basophils
what are the types of granular leukocytes?
lymphocytes and monocytes
what are lymphocytes composed of?
T cells, B cells and natural killer cells
what are the three elements of blood?
- red blood cells
- white blood cells
- platelets
what is erythropoietin?
a hormone which stimulates production of erythrocytes
what is erythropoiesis?
production of erythrocytes
What do platelets contain?
thrombocytes
what is the major function of platelets?
blood clotting
describe the shape of platelets.
irregular cell fragments with a diameter of about 2-4 micrometers
how many platelets are there per microliter of blood?
150,000-400,000
what is hematocrit?
the percentage of blood occupied by RBCs
what is the normal hematocrit for females?
38-46%
what is the normal hematocrit for males?
40-54%
why is hematocrit higher in males?
testosterone produces more EPO synthesis
what is anemia
not enough RBCs or hemoglobin for proper O2 transport
what is polycythemia?
- having an excess of RBCs (over 65%)
- dehydration, tissue hypoxia, blood doping in athletes.
what are erythrocytes shaped like and why?
biconcave discs because it increases the surface area available for oxygen binding
do erythrocytes have a nucleus?
no
how are erythrocytes arranged in large blood vessels?
they are stacked
where are erythrocytes shaped like parachutes?
small arterioles and venules
where are erythrocytes shaped like bullets
capillaries
what are erythrocytes filled with?
hemoglobin
what is hemoglobin?
a protein that carries oxygen
what is hemoglobin composed of?
- 4 large protein chains (2 alpha 2 beta)
- a heme group
what is a heme group in hemoglobin?
a porphyrin ring that surrounds a single iron molecule
how can oxygen molecules can each hemoglobin molecule carry?
4 O2 molecules
what is oxygen bound by?
hemoglobin
what does hemoglobin also transport besides oxygen?
23% of CO2 produced in tissue cells
O2 binds with heme in hemoglobin, what does CO2 bind with?
the globing portion
what is the concentration of hemoglobin in the blood of men? women?
men- 16 g/dL
women- 14 g/dL
what levels diagnose anemia?
hematocrit and hemoglobin levels
where does erythropoiesis occur?
red bone marrow
what are RBCs formed from?
a lineage of precursor stem cells
what do precursor myeloid stem cells differentiate into?
proerythroblasts
what do proerythroblasts turn into?
erythroblast then reticulocytes
how is a mature erythrocyte formed?
a reticulocyte reaches maturity, hemoglobin is produces and the nucleus is rejected
what do hemopoietic growth factors do?
regulate differentiation and proliferation of blood cells
what does erythropoietin (EPO) do?
stimulates eryhtropoiesis and increases RBC precursors
what produces erythropoietin?
the kidneys
what does thrombopoietin do and where is is produced from?
hormone produced from liver and it stimulates platelet formation
what are cytokines
local hormones of bone marrow
what are cytokines produced by and what do they do?
produced by some marrow cells to stimulate proliferation in other marrow cells
what do colony stimulation factors (CSFs) and interleukins in cytokines stimulate?
WBC production
what are some hemopoietic growth factors?
cytokines, erythropoietin, thrombopoietin
what is recombinant EPO effective in?
treating decreased RBC production of end stage kidney disease
what is thrombopoietin (TPO) used for?
to prevent platelet depletion during chemothrapy
how long do RBCs live for?
120 days
why do RBCs only live for so long?
they were out from bending to fit through capillaries and there’s no repair possible due to all of nucleus
what are RBCs removed by and where?
removed by fixed microphages in the spleen and liver
what happens to the breakdown products of RBCs?
they are recycled
what happens to the globin portion of RBCs when they are broken down?
it is broken down into amino acids and recycled
what happens to the heme portion of RBCs when they are broken down?
split into iron (Fe3+) and biliverdin (green pigment)
what does the Iron do after being recycled from RBCs?
- transported in blood attached to transferring protein
- stored in liver, muscle, or spleen (attached to ferritin or hemosiderin protein)
- transported to bone marrow fro use in hemoglobin synthesis
how is biliverdin (green) converted to bilirubin (yellow)?
- bilirubin is secreted by the liver as a part of bile, and bile is secreted into the intestine for use in digestion
- bile breakdown products are excreted via kidneys and intestine
All WBCs have a nucleus but no what?
hemoglobin
what are granulocytes in WBCs?
neutrophils, eosinophils, and basophils
what are agranulocytes in WBCs?
monocytes and lymphocytes
what is the ratio of WBCs to RBCs?
1 WBC for every 700 RBC
what condition is a high white blood cell count?
leukocytosis
what condition is a low white blood cell count?
leukopenia
what causes leukocytosis?
microbes, strenuous exercise, anesthesia or surgery
what causes leukopenia?
radiation, shock or chemotherapy
how much of the total WBC population is circulating in the blood at any given time?
2%
If WBCs are not in circulation where are they?
lymphatic fluid, skin, lungs, lymph nodes and spleen
Where do WBCs travel?
roll along endothelium stick to it and squeeze between cells
what do selectins do?
they are adhesion molecules that help WBCs stick to endothelium
where do WBCs appear?
near the site of injury
where are integrins found and what do they do?.
found of neutrophils and assist in movement through wall
what is phagocytosis?
“cell eating” of bacteria
what is phagocytosis performed by?
monocytes
what does the process of phagocytosis involve?
chemotaxis, adherence and ingestion and destrcution
do eosinophils or monophils have weaker phagocytic activity?
eosinophils
what is chemotaxis?
attraction of phagocytic cells to the site of infection
what happens in chemotaxis?
chemicals released by the pathogen and/ or the infected cell attract the phagocytes
what is adherence?
the attachment of the phagocyte to the pathogens membrane
what is ingestion facilitated by?
enveloping pseudopodia resulting in a phagosome
when is destruction initiated?
when the phagosome fuses with a lysosome resulting in a phagolysosome
what do lysozymes do?
destroy the membrane and internal structures of the pathogen
how are residual fragments of the dead pathogen removed?
exocytosis
how does a bone marrow transplant happen?
- destroy sick bone marrow with radiation and chemothreapy
- put sample of donor marrow into patients vein for reseeding of bone marrow
- success depends of histocompatibility of donor and recipient
what are bone marrow transplants used to treat?
leukemia, sickle-cell, breast, ovarian or testicular cancer, lymphoma or aplastic anemia
