B: Nutrients

Question 1

Macro Nutrients

Answer 1

• Needed in relatively large amounts ( >0.005% of body mass)
• proteins, carbohydrates, fats
• minerals: Na, Mg, K, Ca, P, S, Cl

Question 2

Micro Nutrients

Answer 2

• Needed in less than <0.005% of body mass
  
  • measured in mg (10^-3) or Mg (10^-6)
• Vitamins
• Trace minerals –> enzyme function
  
  • Fe, Cu, F, Zn, I, Se, Mn, Co, B

Question 3

Vitamin A (retinol)

Answer 3

• Conjugation –> electron delocalization –> colored
• large nonpolar section –> fat soluble

Question 4

Vitamin C (ascorbic acid)

Answer 4

• soluble in water –> number of hydroxyl groups which will hydrogen bond to water molecules
• not conjugated –> not colored

Question 5

Vitamin D (D3)

Answer 5

• not colored
• fat soluble

Question 6

Vitamins

Answer 6

• Vitamin C: water soluble –> excreted from the body, needs to be replenished on a regular basis
• Vitamin A and D: dissolved in fat tissue –> can build up to dangerous levets, intake has to be controlled

Question 7

Food

Answer 7

• Vitamin supplements (tablets) / injections
• fortified fruit and vegetables
• genetically modified food

Question 8

Effect of Heat on vitamins

Answer 8

• most vitamins are sensitive to heat
• eg Vitamin C does not get denature –> undergoes an oxidation reaction to form initially dehydroascorbic acid