Flashcards in Chapter 13: Nutrients Involved in Blood Health Deck (37)
____ is needed for single carbon metabolism and methyl transfer
Why is folate needed for cell division? what happens to cell appearance if there is not enough folate?
folate is needed for cells to duplicate because they are used during cytokinesis. Without enough folate, the cells cannot divide properly and appear "blobby" called macrocytic anemia.
Why should one take folate supplement during pregancy
to reduce the chance of neural tube defects?
What is spinabifida? anncephaly?
spinabifida is a result of neural tube defects that makes the spine not close properly. anencephaly results in missing sections of brain and skull, also caused by not enough folate.
Women of child bearing ages should take a ______ supplement
What is another word for cobalamin?
Where is cobalamin produced?
in the gut, by gut bacteria.
What kinds of foods wuld you find vitamin B12 in?
food from animal origin
What three things are needed for Vitamin B12 absorption? Why?
acid, pepsin, and intrinsic factor, a glycoprotein. They are needed because vitamin b12 from food is bound to protein. acid and pepsin release the b12 from the food protein.
what organ secreted intrinsic factor?
cells in the stomach lining. helps with b12 absorption
What happens in the upper portion of the small intestine for B12 absorption? lower portion?
in the upper portion of the SI, the intrinsic factor binds to vitamin B12. inthe lower protion, the B12 intrinsic factor binds to the receptors, allowing absorption.
Can you absorb your own synthisized B12?
no, you must obtain it by eating animal products
How is folate activated? What is active folate used for?
B12 activates folate. the active folate then is used for methyl transfer, regeneration of folate etc.
Why is B12 needed for proper nerve conduction?
B12 maintains the myelin coating on nerves. it is essential for nerve transmision.
Why may an individual with pernicious anemia have affected b12 levels
pernicious anemia destroys the stomach lining that creates intrinsic factor, which is salient for the proper absorption of B12.
What is atrophic gastritic? why may this disease affected B12 absorption?
inflammation of the stomach lining which affects stomach acid secretion and reduces intrinsic factor. wihtout enough acid and digestive enzymes, the b12 cannot be torn apart from the protein complex it resides in in food. without intrinsic factor, the b12 cannot be absorbed in the small intestine.
What're the three forms of vitamin B6? what do they all convert into?
pyridOXAL, pyridOXINE, pyridOXAMINE. All types are converted into Pyridoxal phosphate, an active coenzyme.
4 Main functions of B6
1) Hb synthesis
2) myelin synthesis (along with B12)
3) amino acid and neurotransmitter synthesis
4) immune function and WBC synthesis.
What type of anemia is caused by vitamin B6 deficiency? why? what is the disease characterized by
can cause microcytic anemia, RBCs look like small pale cells. It's cause RBC's are involved in hemoglobin protein synthesis.
What is homocysteine?
an intermediate in the blood involved in methionine metabolism
if you have too much homocysteine in the blood you are at risk for ____
higher risk of CVD
What is the relationship between Folate, B12, B6 and homocysteine?
Folate, b12 and b6 are all involved in the methyl transfers used to make methionine into homocysteine. When methionine turns into homocysteine, B12 is regenerated and active folate is converted back into body folate. Homocysteine then turns into cysteine by the help of B6 and methyl transfers
Whats the difference between phylloquinines and menoquinones
phylloquinones are vitamin K species in plants, and menoquinones are vitamin K species in animals
Four main functions of vitamin K
1) is a cofactor used to make prothrombin and specific clotting factors
2) makes functional proteins
3) used in bone health and demineralization
4) keeps bood vessels elastic by preventing calcification of blood vessels.
What're the two forms of iron
1) heme iron: Fe2+, used in Hb and Mb, found in animal products
2) non heme iron: Fe3+, found in plants. needs vitamin C to convert to heme iron.
Where is Fe2+ iron absorbed
Fe absorbed into SI cells.
Why would calcium aid in the absorption of Fe?
It wouldn't. Calcium actually affects the absorption of Fe2+, increasing the likelihood of the iron supplement just being peed out
Where is iron stored? What form is it stored as?
in the liver and spleen. Stored as ferritin and hemoseridin.
What factor enhances non heme iron absorption?
the meat fish poultry MFP factor.