Biochemistry: Vitamins and Minerals

  1. Fat soluble vitamins require _______ for absorption and are stored in the ______________
    bile acids, liver and adipose
  2. Vitamin A (retinol) is important for:
    • Proper vision
    • Normal growth
    • Differentiation
    • Reproduction
  3. Vitamin A (retinol) is found in:
    Liver, milk, eggs, cereals, multivitamins
  4. Vitamin A (retinol) deficiency leads to:
    • Night blindness
    • Dry eyes leading to corneal damage
    • Urinary stones
  5. What is the limit for excess vitamin A? List the signs of acute toxicity.
    • > 66,000 IU/day
    • Signs of acture tox: nausea, vomting, headache, blurred vision, muscular uncoordination- doubles risk of hip fracture
  6. List the sources of beta carotene.
    Yello/orange fruits and veggies, dark leafy greens, spinach broccoli
  7. Vitamin E (alpha-tocopherol) serves as a/n _____________. Deficiency is usually due to ____________.
    Antioxidant, malabsorption
  8. Vitamin E deficiency may lead to:
    • Necrotizing myopathy
    • Neurological problems due to poor nerve conduction
    • Anemia due to oxidative damage to RBCs
    • Retinopathy
    • Infertility
    • Atherosclerosis and cardiovascular disease (bc vitamin E may prevent oxidation of LDL or polyunsaturated fats.
  9. List sources of vitamin E
    Nut, seeds, wheat germ, rice bran, veggie oils, margarine, shortening
  10. High doses of vitamin E may cause:
    bleeding complications
  11. How is vitamin D synthesized?
    From cholesterol via UV radiation (to 7-alpha dehydro cholesterol) and then dehydroxylated to 1,25-dehydroxy vitamin D3
  12. When should you take vitamin D suppllements and how much should you take?
    If you live further north than LA/Florida between Oct-May. Take 100-400 IU (2.5-10 ug/day). The elderly have more risk factors so they should take > 400 IU.
  13. Who is at greater risk for vitamin D deficiency?
    • The elderly have more risk factors so they should take > 400 IU.
    • Women of chid-bearing age
    • Children
    • People with darker skin
    • People who are lactose intolerant
  14. What is Rickets?
    A disease of vitamin D deficiency esp common in newborn Af Am children. COntributing factors include: urban living, sun screen use, lack of health care to poor populations.

    • Rickets in children results in:
    • “Squared’ head
    • Chest deformity
    • Spine abnormality
    • Bowing of the legs

    Vitamin D deficiency in adults: Osteomalacia with weakening of bone and fracture
  15. What are some of the functions of vitamin K?
    Required in carboxylation reactions in the liver. Activate clotting factors and osteocalcin (inhibits calcification)
  16. What are some causes of vitamin K deficiencies and what happens?
    • Vitamin K deficiency can be caused by: malabsorption and/or warfarin therapy.
    • Newborns: deficiency from sterile gut or poor placental transfer.
    • Leads to: Excessive bleeding, calcification of arteries and cartilage, aberrant calcification, chondrodysplasia punctata (a diorder of bone and cartilage that leads to dwarfism)
  17. List the water soluble vitamins
    • Vitamin C
    • Riboflavin
    • Niacin
    • Bitamin B6
    • Folic acid
    • Vitamin B12
    • Biotin
    • Pantothenic acid
  18. Which of the following vitamins are invilved in energy production and which are hematopoietic?
    Vitamin C
    Bitamin B6
    Folic acid
    Vitamin B12
    Pantothenic acid
    • Energy generation:
    • Vitamin C
    • Riboflavin
    • Niacin
    • Biotin
    • Pantothenic acid

    • Henatopoietic:
    • Bitamin B6
    • Folic acid
    • Vitamin B12
  19. Number the B vitamins 1-3, 5, 6, 12
    • The Real News for Political Pundits & Cronies
    • Thiamine: B1
    • Riboflavin: B2
    • Niacin: B3
    • Pantothenic acid: B5
    • Pyridoxine: B6
    • Cobalmin: B12
  20. With what patients do we most commonly see vitamin B deficiency? What are syndromes associated with each B vitamin deficiency?
    Most commonly seen in alcoholics and with "fad" diets.

    • B1 (thiamine)—Beriberi; and Wernicke syndrome (in chronic alcoholics)
    • B2 (riboflavin)—Deficiency rare (due to grains and cereal fortified with B2)
    • B3 (niacin) –Pellagra (Tryptophan and Niacin deficiency)
    • B6 (pyridoxine)—Severe symptoms include seizures (due to
    • inability to make GABA)
    • Biotin –Deficiency rare (due to GI bacteria which make biotin)
  21. What is the responsible for copper absorption? Which other mineral also cometitively uses it?
  22. What is Menkes syndrome?
    • Cu deficiency syndrome
    • Mutations in copper transporting ATPase (ATP7A)
    • Leads to brittle/kinky hair, hereditary malabsorption, brain deterioration and is eventually fatal
  23. What is Wilson's disease?
    • A disease of copper accumulation that presents in the first or second decade of life.
    • Mutations in copper transporting ATPase (ATP7B)
    • Leads to Kaise-Fleischer ring in cornea
    • ABCD: Asterixis (tremor of the wrist); Basal ganglia degeneration (parkinsonian symptoms); Ceruloplasmin low (Cu transport); Dementia
    • Treated with chelators like penicillamine.
  24. How is zinc absorped?
    Metallothianein-dependant absorption
  25. What are the results of zinc deficiency?
    • Poor growth, sexual development
    • Poor taste acuity- gustin (needed for development of taste buds)
    • Poor wound healing
Card Set
Biochemistry: Vitamins and Minerals
Gi absorption of vitamins and minreals