Hematology - RBC
What is the normal shape of a RBC? List 2 benefits to this. - ANS 1. Thin,
biconcave disc
2 benefits to this shape: 1. flexible through capillaries 2. better diffusion of
oxygen
What is the average lifespan of a RBC? - ANS 120 days
What happens to RBC after 120 days? - ANS They lose their elasticity. They
become trapped in small blood vessels, esp. in the spleen. Most of the iron is
recycled.
___________ makes up 95% of the mass of a RBC. - ANS Hemoglobin
What is the function of hemoglobin? What are the functional components? - ANS
To bind O2 and CO2. Heme - made of iron to transport O2. Globin - made of
protein to carry CO2.
What hormone is produced in the kidneys that stimulates bone marrow to
produce RBCs? What triggers this to happen? - ANS Erythropoietin. It is
produced by the kidneys when tissue oxygenation is decreased (hypoxic).
What performance enhancing drug is naturally produced by the body? Why is it
used? - ANS Erythropoietin. It is used to increase O2 carrying capacity. Cyclists
use this drug often.
What hormone is formed in the liver, kidneys, and in the stromal cells of bone
marrow? What does it do? - ANS Thrombopoietin. It stimulates production of
thrombocytes, aka, platelets.
What are the essential components for RBC production? - ANS 1. Iron
2. Folic Acid
3. B12
Name dietary sources of Iron. - ANS Iron dietary sources include: meat, green
leafy veggies, OJ doubles the absorption of iron from a meal.
, What increases iron absorption from a meal? - ANS OJ
Liver, green leafy veggies, legumes, beets, broccoli, cauliflower, citrus fruits,
sweet potatoes, and fortified grains are a source of what vitamin? - ANS Folic
Acid - a B-complex vitamin needed to produce RBCs. Deficiency in folic acid can
lead to certain types of anemia.
What vitamin is synthesized in the GI tract? What does it do? Where is this
vitamin also found? - ANS B12. Is an essential component for RBC production. It
is also found in meat, yeast, milk, eggs
What trace elements are needed for RBC production? Where are those elements
found? - ANS Copper, cobalt, nickel and B6.
Meats, liver, cereal grains, bananas, nuts.
What determines blood type? - ANS The antigen found on the RBC membrane.
O negative blood is the ___________ _________. - ANS Universal donor
AB positive is the ______________ ____________. - ANS Universal recipient
What is Hct? - ANS Hematocrit. It is a percentage of packed RBCs within a
volume of whole blood. Measurement depends on the number and size of RBC's.
What lab value constitutes a low Hct? Name a few conditions that result in low
Hct reading. - ANS < 37% . Anemia, bleeding, destruction of RBC's, leukemia,
malnutrition, nutritional deficiencies of iron, folate, vitamin B12, and vitamin B6,
overhydration.
What is a normal range for Hct? - ANS 37%-47% (% is usually higher for men)
What lab value constitutes a high Hct? Name a few conditions that result in high
Hct reading. - ANS Congenital heart disease, cor pulmonae, dehydration,
erythrocytosis/polycythemia (abnormal increase in number of circulating RBC's),
hypoxia, pulmonary fibrosis.
What is the "baby red blood cell" lab value? Why is it important? - ANS Retic
count - reticulocytes - immature RBC's that still have a nucleus. Should be 1-2%