Micronutrients (Type II Receptors) Part 2 whoops Flashcards
Vitamin K is important for:
- bone formation
- blood coagulation
Is vitamin K deficiency common or rare? Why?
- Rare
- Gut bacteria makes it
Phylloquinone is a type of vitamin ____ that comes from ____ and has a(n) ____ side chain
K ; Plants ; saturated
Menaquinone is a type of vitamin ____ that comes from ____ and has a(n) ____ side chain
K ; Gut Bacteria ; unsaturated
How is vitamin K transported around the body?
in chylomicrons
What is the difference between how Menaquinones and Phylloquinones are absorbed?
- Phyloquinone absorbed via NPC1L1 transporter
- Menaquinone absorbed passively
What does Warfarin do?
- inhibit epoxide reducates in the vitamin K cycle
- prevents the regeneration of Vitamin K quinone
What is the active form of vitamin K in the vitamin K cycle? Is it the oxidized or reduced form?
Hydroquinone ; reduced
What is the inactive form of vitamin K in the vitamin K cycle? Is it oxidized or reduced?
Epoxide ; oxidized
What are the enzymes involved in the vit. K cycle in order starting from quinone?
Quinone reductase, y-glutamyl carboxylase, epoxide reductase
What do Gla residues do?
On blood clotting proteins ; bind Ca2+/ Ca2+ allows Gla-containing proteins to bind to phospholipids on membranes of blood platelets and endothelial cells
Where is most of the calcium in the body?
- bones
- teeth
Calcium absorption is mediated by ____ (carrier-mediated active transport)
calcitriol
How is Calcium transported in the body?
- bound to albumin
- complexed with sulfate, phosphate etc.
- free in ionized form
What are the functions of calcium?
- blood clotting (Gla residues)
- skeletal muscle contraction
- nerve potential
- intracellular signaling pathway
