Blood 3 Flashcards
What is the shape of an RBC?
Biconcave disc
What is the diameter of RBCs?
7 or 8 microns
What is the lifespan of a RBC?
120 days
Why is an RBCs lifespan so short?
Because when they mature, they don’t have a nucleus or other organelles to continue living
When do RBCs lose their organelles?
Shortly before leaving the bone marrow
Why do RBCs lose their organelles?
To make more room for Hemoglobin
Where in a RBC is oxygen bound?
To hemoglobin
What is an advantage to the biconcave shape of RBCs?
It makes it more flexible
What are the 2 main parts of Hemoglobin?
Heme (non-protein) + Globin (protein)
What is the Globin of Hemoglobin made of?
A non-polypeptide of amino acids that is folded back on itself many times
How many Globins are in a single Hemoglobin molecule?
4
What is the shape of Heme of hemoglobin?
Roughly ring shaped
What is in the center of a Heme molecule?
An charged iron atom Fe2+
What are the coordination bonds of heme used for?
- 4 for used in binding ferrous iron to part of the heme ring
- 1 used to bind ferrous iron to globin
- 1 used to bind to oxygen
Name and describe the process of oxygen binding to Ferrous Iron?
The process is known as oxygenation and ferrous iron remains in the
How many Globin and how many Heme molecules are there in a single hemoglobin?
4 Heme and 4 Globin
What are the 2 types of Globin chains in Hemoglobin?
Two alpha chains and two beta chains
What is the difference between Alpha and Beta Globin chains?
They have minor changes in their amino acid composition
What is each Heme associated with?
An alpha or beta globin
What is at the center of a Heme unit?
Iron
Why is Iron important in the Heme molecule?
Its the part that actually binds to oxygen
How do RBCs get iron?
We ingest it in food and transport system take it out of the lumen of the small intestine and take it to the blood which takes it to the bone marrow which uses it to make RBCs which make hemoglobin with it
Where are RBCs destroyed at the end of their life cycle?
In the spleen
What does the spleen do with the RBCs that are released from broken down RBCs?
They release the iron back into the bloodstream to be reused
