chapter 3- biological molecules

Question 1

what are carbohydrates?

Answer 1

nutrients

Question 2

what are the disaccharides of carbohydrates?

Answer 2

maltose, sucrose, lactose

Question 3

what are the smallest unit of carbohydrates? (simple sugars- monosaccharides)

Answer 3

glucose, fructose, galactose

Question 4

what is the test for reducing sugars? state its original colour and colour change when reducing sugar is present.

Answer 4

Benedict test. blue. it changes from blue to green when there are little reducing sugars are present. blue to yellow when there is moderate amount of reducing sugars present and brick-red when there is a high amount of reducing sugars.

Question 4

what are the polysaccharides of carbohydrates?

Answer 4

glycogen, starch, cellulose

Question 5

what is the test for fats? state its original colour and colour change when fats is present.

Answer 5

Ethanol emulsion test. its original colour is colourless and will have a white emulsion when fats are present.

Question 6

what is proteins made up of? (in terms of chem also)

Answer 6

carbon, hydrogen, oxygen and nitrogen

Question 6

what are fats made up of? (in chem terms also)

Answer 6

carbon. hydrogen and oxygen; made up of glycerol and 3 fatty acids

Question 7

what is the test for starch? state its original colour and colour change when starch is present.

Answer 7

iodine. brown to blue-black when starch is present.

Question 8

what is the function of fats?

Answer 8

store large amounts of energy, prevent loss of body heat and is a cushion for vital organs.

Question 9

what is the smallest unit of protein?

Answer 9

amino acids

Question 10

what is the formation of protein?

Answer 10

amino acids to peptide to proteins

Question 11

what is the test for proteins? state its original colour and colour change when protein is present.

Answer 11

biuret test. the colour changes from blue to violet when protein is present