Human Phys 7.3 Flashcards
What are vitamin B12 and folic acid essential for?
Maturation of RBC
DNA synthesis
Why do RBC become much larger than normal?
Failure to proliferate rapidly
What causes RBC to have a short life that is 1/2 to 1/3 normal?
Their fragility
What do parietal cells of the gastric glands secrete?
Glycoprotein called intrinsic factor
What is intrinsic factor required for?
Vitamin B12 uptake by binding to B12 and protecting it from digestion
What does lack of vitamin B12 cause?
Macrocytic normochromic anemia
What % of total body iron is bound to heme in RBC and muscle cells?
67%
How much iron is stored in macrophages and hepatic paranchymal cells?
30%
How much iron is lost daily in sweat, urine, bile, and minor bleeding?
3%
How much iron is required daily for erythropoiesis?
25 mg
What is the dietary recommendation of iron daily?
1-2 mg the rest is from continual recycling of RBC
Microcytic-hypochromic anemias
Red cells that are abnormally small and contain reduced amounts of hemoglobin
What is microcytic-hypochromic anemia related to?
Disorders of iron metabolism
Disorders of globin synthesis
What is the most common type of anemia worldwide?
Iron deficiency anemia
What is iron deficiency anemia caused by?
Nutritional iron loss
Blood loss