Exam 2 -- Hematology #1 Flashcards
What is the function of blood?
Carries nutrients, Abs, hormones, oxygen, and waste; forms clots, regulates body temperature through vasodilation and constriction
What are the components of blood?
55% plasma (which is 90% water and 10% proteins), 44% RBCs, and 1% WBCs and platelets
What are the types of white blood cells?
Leukocytes (monocytes, basophils, eosinophils, neutrophils) and lymphocytes (B cells, T cells, and natural killer cells)
Where does hematopoiesis occur (in adults)?
Mostly in the bone marrow, though it can occur in the liver and spleen if there is a severe enough need.
Red bone marrow contains stem cells that differentiate into ________, ___________, and _____________.
RBCs, WBCs, and platelets
How long do RBCs live?
About 120 days
Erythropoietin is produced in what organ(s)?
Kidneys (90%) and liver (10%)
Starting with the pronormoblast, list the stages of development of an erythrocyte (RBC).
Pronormoblast–>Normoblast, which then expells its nucleus and is released from the bone marrow and becomes a–>Reticulocyte, which circulates for a couple of days until it is finally a mature–>Erythrocyte
What roles do vitamins B12, B9, and B6 have in terms of blood?
B6 helps with hemoglobin creation; B9 helps with RBC creation; B12 helps with both
How many hemoglobin molecules are there per RBC?
280 million
What is the basic structure of hemoglobin?
Four heme groups (with iron), two alpha globin chains and two beta globin chains
When and where does hemoglobin synthesis occur?
In mitochondria of developing RBC in the bone marrow
Hemoglobin has two formations – T and R. Which formation has low affinity for oxygen?
T formation (Taut, or Tight, oxygen can’t get in)
Hemoglobin has two formations – T and R. Which formation has high affinity for oxygen?
R formation (Relaxed)
What is the Bohr effect?
A phenomenon in which oxygen dissociates from hemoglobin wherever CO2 concentrations are high (which acidifies the blood); oxygen associates with hemoglobin wherever CO2 concentrations are lower (higher blood pH).
When it is time for a RBC to die, it is sent to the spleen. What happens to the hemoglobin?
The heme and globin portions are dissociated from each other. The iron is removed from the heme portion, and the heme portion is converted to bilirubin. Bilirubin is transported from the spleen to the liver. The liver converts bilirun to bile to be used in digestion. Eventually bilirubin is excreted by the kidneys.
Mean corpuscular volume (MCV) measures what?
The average volume of RBCs.
Anemia is defined as decrease in what?
RBCs or hemoglobin
Which gender has a higher prevalence for anemia?
Females
What are the symptoms of anemia?
Fatigue, HA, fainting, angina, claudication, palpitations
What are the signs of anemia?
Pallor, tachycardia, cardiac failure, brittle or spoon shaped nails, pica (eating things that have no nutritional value)
Types of anemia can be based on the mean cell volume and/or hemoglobin concentration (too little, normal, too much) or a shortened lifespan of RBCs. What is the MCV of microcytic anemia?
Less than 80 fL (normal is 88 fL)
What are the different types of microcytic anemias?
Iron deficiency anemia, thalassemia, and sideroblastic anemia
True or false: sideroblastic anemia is the most common cause of anemia
False; iron deficiency anemia is the most common cause of anemia
Amongst men, women, and children, which are more commonly affected with iron deficiency anemia?
Women and children –women lose more blood, children have higher need because of growth phases
How much iron is normally absorbed by the body? How much can be absorbed if iron is taken as a supplement?
10% normally absorbed; 20-30% in supplements
Where can iron be stored in the body?
Liver, spleen, bone marrow
What are some causes of iron deficiency anemia?
Blood loss, pregnancy, growth phases, poor diet, celiac disease (malabsorption), NSAIDs (GI bleeding), gastric bypass surgery
What is the CDC recommended daily intake of iron for individuals 30 years of age?
Men: 11 mg/day; women: 18 mg/day