bio lab biomolecules

Question 1

Carbohydrates

Answer 1

Carbon hydrogen oxygen in ratio of 1:2:1

Question 2

Lipids

Answer 2

Hydrophobic bc nonpolar, lack oxygens have carbons and hydrogen

Question 3

Proteins

Answer 3

Pattern of C-C-N backbone

Question 4

Benedict’s test

Answer 4

Carbohydrates testing: Color teal blue, if negative doesn’t change color, needs heat to open up monosaccharide rings of sugar, works on some disaccharides not all and doesn’t work on polysaccharides like starch

Question 5

Lugols iodine test

Answer 5

Carbohydrates testing: color yellow-brown, changes to blue, violet, black in presence of starch, testing for polysaccharides (large carbohydrates), no heat needed, added to sample and mixed, to read if too dark look at sides during vortexing

Question 6

Sudan IV Test

Answer 6

Lipid testing: color pink, add reagent and water, no color change if negative, pink if lipids are present, lipids will stain red/pink and rise to top

Question 7

Biuret reagent

Answer 7

Protein testing: indigo blue color, negative will stay blue, positive will change to violet, is a skin irritant wash if in contact for 15 minutes