4. Vitamin requirements vary from species to species and are influenced by age, sex, and physiological conditions such as pregnancy, breast-feeding, physical exercise, and nutrition.

5. :Vitamins are classified as The lipid-soluble vitamins include vitamins A, D, E, and K the water-soluble vitamin include vitamins B1(thiamin),B2 (riboflavin),folic acid (folcine), H(biotin). Color atlas of biochemistry

8. Harper’s Illustrated Biochemistry

9. In the body, biotin is covalently attached via a lysine side chain to enzyme that catalyze carboxylation reactions. Biotin-dependent carboxylases include pyruvate carboxylase and acetyl-CoA carboxylase.

10. CO2 binds, using up ATP, to one of the two N atoms of biotin. Play an important role in fat, amino acid,and carbohydrate metabolism. Color atlas of biochemistry

11. Biotin deficiency is extremely rare. Some potential causes of biotin deficiency are: intravenous feeding. eating raw egg whites on a regular basis. carboxylase deficiency. Supplementing with biotin appears helpful for the treatment of this deficiency. http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-biotin.html

12. Impaired fat and carbohydrate metabolism alopecia and a characteristic scaly, erythematous dermatitis Harper’s Illustrated Biochemistry, www.pubmed.com

14. Folacin * Folic acid, folate,vit.B9 *water-soluble vitamin

15. Source

16. Biochemical role - Essential role in Metabolism -Red blood cells, white blood cells, or cells of the intestinal mucous membrane pharmacotherapy

17. Biochemical role monoglutamate Small intestine tetrahydrofolate cobalamin-dependent reaction Folacin (polyglutamate form ) pharmacotherapy

18. tetrahydrofolate Biochemical role choline methionine pyrimidine carrier purine

19. Biochemical role - decrease the incidence of neural tube defects without masking occult vitamin B12 deficiency.

20. Deficiency of folacin Causes: Inadequate dietary intake malnutrition malabsorption increased utilization Martindale

21. Risk factors: * Pregnancy or lactation *malignancy *liver disease *alcoholism *chronic hemolytic anemia *Elevated homocysteine level in the blood http:/www.springboard4health.com

22. Symptoms: *Sore mouth *Diarrhea *Irritability and forgetfulness Handbook of nonprescription drugs

23. Diseases *Megaloblastic Anemia - -Affects cells that are dividing rapidly - they have a large requirement for thymidine for DNA synthesis. - affects the bone marrow http:/www.springboard4health.com

24. Diseases *environmental carcinogens. * promotes the breakage of chromosomes at fragile sties. *prohibit normal differentiation and replication