Blood Physiology Lecture 2 Flashcards
3 Essential Factors for RBC production
- Cytokines
- Dietary Factors
- Intrinsic Factors
Cytokines as essential factors in RBC production
erythropoietin (EPO) stimulates RBC production
Dietary factors as essential factor in RBC production
iron needed in Hb, folic acid, and vitamin B12
Intrinsic factors as essential factors in RBC production
made by cells in the stomach and needed for absorption of
vitamin B12
Steps of regulation of RBC production by Erythripotein
- Low oxygen delivery to kidney (hypoxia)
- Secretion of erythropoiten
- Increases production or red blood cells by the bone marrow
- Increased hemoglobin concentration
- Increased carrying capacity of oxygen in blood
- Restoration of oxygen delivery
hypoxia
low oxygen concentration in blood
3 categories contributing to hypoxia:
- Anything that affects bloods ability to carry oxygen
- Anything that affects delivery of oxygen to tissues
- Anything that affects a persons ability to take in oxygen
Factors that can affect blood ability to carry oxygen (5)
- Low blood volume
- Anemia
- Low hemoglobin
- Poor blood flow
- Pulmonary Disease
Factors that reduce oxygens delivery to the tissues (3)
- Low blood volume
- Anemia
- Low hemoglobin
Factor that affects blood’s ability to take in oxygen
Pulmonary Disease
Iron is needed for ________
production of red blood cells
Uptake and Recirculation of Iron steps ( )
- Iron is obtained from food, and is absorbed into the blood in the intestine
- In the blood iron is transported and bound to transferrin (iron transport protein)
- Iron is carried by transferrin to the bone marrow where it is used to make hemoglobin for RBC
The body maintains an iron _______
balance
How can the body loose iron (3)
- sweat
- urine
- menstrual flow
How can the body increase iron levels if you are loosing a lot? (2)
- By increasing rate of absorption of iron in intestines
- Using the ones from the bodys reserve
Body Iron reserve composition
-50% of the iron is from Hb from dying RBC
-25% of the iron is stored in other iron-containg protein
-25% is stored in liver bound to ferritin (a protein)
Where may bilirubin end up (2)
-Urine
-Fecal waste
Recycling of iron from old/damaged RBC’s steps (4)
- Old or damaged RBC is taken up by macrophages in spleen by phagocytosis
- Hemoglobin is broken down into heme and globin
- Heme is broken down into iron and biliverdin
-Iron is absorbed into the blood for erythropoiesis or stored in the spleen or liver bound to ferritin
-Biliverdin is converted to bilirubin, and then secreted into bile and enters the small intestine
- Globin is broken down into amino acids
Vitamin B12 is required for _______
normal production of RBC
Where is Vitamin B12 obtained from?
a persons diet
Absorption of Vitamin B12 steps
- Vitamin B12 will go from food into stomach
- Intrinsic factors (protein) will be secreted by cells in stomach wall
- Vitamin B12 and Intrinsic Factors will form a complex (B12/IF complex) in the small intestine
- B12 is absorbed into the blood
Pernicious anemia is due to _______
a lack of vitamin B12
Anemia is the ______
decreased oxygen-carrying capacity of the blood due to a deficiency of RBCs and/or hemoglobin contained in the RBCs
Factors leading to anemia:
- Lack of iron
- Lack of intrinsic factors or Vitamin B12 (prenicous anemia)
- Damage of bone marrow due to radiation/drugs (aplastic anemia)
- Chronic kidney disease (reduces the level of erythropoiten (EPO)
- Increaseds breakdwon due to abnormal shape of RBC or due to immune reactions during transfusion (Hemolytic Anemia)
- Hemorrhagic anemia: increased blood loss due to injury, bleeding ulcer or chronic menstruation
- abnormal structure of hemoglobin
