Term
| Name the earliest cell destined to become an RBC |
|
Definition
|
|
Term
| What is the first cell to have receptors for erythropoetin? |
|
Definition
|
|
Term
| List the erythroid developmental line |
|
Definition
Multipotent stem cell
BFU-E
CFU-E
Proerythroblasts 4 types below
- basophilic erythoroblast
- polychromatophilic
- orthochromatophilic
- reticulocytes
Red cells |
|
|
Term
|
Definition
| an obligatory growth factor for erythroid development |
|
|
Term
| Where is erythropoetin produced? |
|
Definition
| in the peritubular cells of the kidney |
|
|
Term
| What is the trigger for the synthesis of erythropoetin? |
|
Definition
| a heme containing protein within erythropoetin that senses oxygen need |
|
|
Term
| What stimulates the production of RBC's? |
|
Definition
| Erythropoetin transpoted through the blood to bone marrow where it binds to receptors on the CFU-E |
|
|
Term
| What happens to RBC production in renal failure? |
|
Definition
| it will decrease b/c the growth factor erythropoetin is made in the kidney, this is known as the anemia of kidney failure |
|
|
Term
| What happens to RBC production during hypoxia? |
|
Definition
| It will increase b/c low oxygen tension is the trigger for the synthesis of erythropoetin by the peritubular cells of the kidney |
|
|
Term
| What is the life span of an RBC? |
|
Definition
|
|
Term
| How many times will a RBC circulate through the heart in its lifetime? |
|
Definition
|
|
Term
| More than 95% of an RBCs protein is this? |
|
Definition
|
|
Term
| What is the shape of an RBC? |
|
Definition
|
|
Term
| why is an RBC's shape important? |
|
Definition
| it facilitates gas transfer |
|
|
Term
| What important property of the RBC does the cytoskeleton allow for? |
|
Definition
|
|
Term
| Abnormalities of the cytoskeleton lead to what in RBC's? |
|
Definition
| pathological shapes such as elliptocytes and spherocytes |
|
|
Term
| What is the RBC cytoskeleton composed of? |
|
Definition
- glycolipids
- phospholipids
- integral proteins
- transmembrane proteins
|
|
|
Term
| what are the 4 most well studied cytoskeleton proteins? |
|
Definition
- ankyrin
- spectrin
- band protein 4.1
- band 3 protein>
|
|
|
Term
| What happens to RBC's when the cytoskeleton is abnormal? |
|
Definition
| abnormalities within cytoskeleton proteins lead to disorders where the RBC can't deform in the capillary beds and will die |
|
|
Term
|
Definition
| a newly formed erythrocyte |
|
|
Term
| what differentiates a reticulocyte from a RBC? |
|
Definition
| reticulocytes still contain some RNA that remains for 1-2 days after the cell enters circulation, one that goes away it is a mature erythrocyte |
|
|
Term
| What is the normal reticulocyte count and how do we determine it? |
|
Definition
| 1% of erythrocytes in circulation and we stain with supravital stain to obtain the reticulocyte count |
|
|
Term
| Under what conditions would you see an increaded reticulocyte count? |
|
Definition
| anemia, where the response is to increase RBC production |
|
|
Term
| From what causes of anemia would you see a low reticulocyte count? |
|
Definition
| with bone marrow problems and iron deficiency |
|
|
Term
| What is the purpose of hemoglobin? |
|
Definition
| to reversibly bind oxygen |
|
|
Term
| How much more oxygen can hemoglobin+plasma carry vs. plasma alone? |
|
Definition
|
|
Term
|
Definition
| it is a complex of iron and protoporphyrin |
|
|
Term
| What is the structure of a hemoglobin molecule? |
|
Definition
| a tetramer consisting of 2 pairs (4 total) similar polypeptide chains and to each of the 4 chains is attached a heme (iron and protoporphyrin) |
|
|
Term
| Where is the hemoglobin alpha gene locus and what two proteins does it produce? |
|
Definition
| chromosome 16 and globins alpha and sigma(only during first 8 weeks of fetal development and will mature into alpha) |
|
|
Term
| Where is the hemoglobin beta gene locus and what protiens does it produce? |
|
Definition
| chromosome 11 and produces fetal hemoglobin and adult hemoglobin (delta & beta) |
|
|
Term
| RBC's containing which hemoglobin have the highest affinity for O2? |
|
Definition
|
|
Term
| what are the normal hemoglobin components in adults? |
|
Definition
| Hgb A1 (a2b2), A2(a2d2), and up to 2% F (a2f2) |
|
|
Term
| What happens to the hemoglobin in pediatric popultion with increasing age? |
|
Definition
| HbF can be as high as 80% in a newborn and will decrease to look more like the normal adult count |
|
|
Term
| What two types of hemoglobin should never be seen in panel? |
|
Definition
| 2 abnormals= HgS (sickle cell) and HgC (abnormal) |
|
|
Term
| What are the requirements for hemoglobin to function as an exchange medium between O2 and CO2? |
|
Definition
- capable of transporting large amounts of O2
- Highly soluble
- Take up and release O2 at appropriate pressures
- be a good buffer
|
|
|
