Term
| Where does heme synthesis take place? |
|
Definition
| In reticulocytes and hepatocytes |
|
|
Term
| What molecules are needed to perform heme synthesis and what processes are these molecules coming from? |
|
Definition
Succinyl CoA- TCA
Glycine
Iron |
|
|
Term
| What is the first enzyme in the synthesis pathway of heme? |
|
Definition
| Aminolevulinic acid synthase (ALA) |
|
|
Term
| What cofactor is required for ALA synthase? |
|
Definition
|
|
Term
| What is needed and what inhibits ALA synthase in the heme synthesis pathway? |
|
Definition
| ALA synthase requires B6 as a cofactor and heme acts as an inhibitor. |
|
|
Term
| What effect does heme have on the heme synthesis pathway? |
|
Definition
Heme- has a negative feedback effect on ALA synthase.
-inhibits gene expression for alpha and beta globin chains along with ALA synthase genes. |
|
|
Term
| What effect does lead have on heme synthesis? What is the result of this? |
|
Definition
Lead inhibits two enzymes.
Can lead to
-anemia
-lower energy production due to decreased heme containing cytochromes for oxidative phorylation to occur. |
|
|
Term
| Where does most iron storage occur? |
|
Definition
|
|
Term
| What protein transports iron in the blood stream? |
|
Definition
|
|
Term
| What does TIBC mean? Does it increase or decrease during iron deficiencies? |
|
Definition
| Total Iron Binding Capacity. Increases in iron deficiencies. |
|
|
Term
| What protein is used for long term iron storage? |
|
Definition
|
|
Term
| What protein is used for absorbing iron in the gut and also for short term storage? |
|
Definition
|
|
Term
| What are the three proteins that are used for iron transport and absorption? What are their functions? |
|
Definition
-transferrin-transports iron in the blood
-ferritin-gut absorption and short term storage
-hemosiderin-long term storage of iron |
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