Flashcards in Biochem - Fat Soluble Vitamins Deck (19):
What are the differences between fat and water soluble vitamins?
Fat soluble vitamins:
-Require bile for digestion and absorption
-travel through lymphatic system
-many require transport proteins in bloodstream
-excess is stored in liver and adipose tissue
-not readily excreted (so risk of toxicity is greater)
What is the precursor for Vitamin A?
Vitamin A's role in cell differentiation, reproduction, and growth :
Normal fetal development
Growth of children - bone remodeling
3 forms of vitamin A in the body
Retinal - vision
Retinol - reproduction
Retinoic acid - growth
Vitamin A deficiency
Vitamin A toxicity
*no effect on acne
Vitamin D forms
D2 from plants (ergocalciferol)
D3 from animals (cholecalciferol)
Not an essential nutrient
Roles of Vitamin D
Protects against cognitive decline
Can enhance or suppress gene activity
Vitamin D deficiency
Production of calbindin, a protein that binds calcium in intestinal cells
-so this can create Ca deficiency
Rickets (children, bones bend)
Osteomalacia (adults, soft, brittle, flexible, deformed bones)
Vitamin D toxicity
Raises blood [Ca]
Forms stones in soft tissues
May harden blood vessels
Can cause death
Sources of vitamin D
Subgroups of Vitamin E?
Compounds of each?
Which are maintained in the body?
Each contains 4 compounds:
*only alpha tocopherol maintained in the body
Vitamin E is useful because__
-heart disease and protection of LDLs
Vitamin E deficiency
2 conditions respond to Vitamin E treatment.
Fibrocystic breast disease
Vitamin E toxicity
-liver regulates concentrations
High doses may interfere with vitamin K activity
Primary action of Vitamin K?
Metabolism of bone proteins
Vitamin K deficiency
Primary deficiency is rare
Fat absorption falters
Some drugs alter synthesis and action
Newborns have a sterile intestinal tract
They are given a single dose of vitamin K at birth