Biological molecules Details

Question 1

Chemical elements that make up carbohydrates

Answer 1

-Carbon(C)
-Hydrogen(H)
-Oxygen(O)

Question 2

Ratio of elements(carbon to hydrogen to oxygen) in carbohydrates

Answer 2

1:2:1

Question 3

Chemical elements that make up fats

Answer 3

-Carbon(C)
-Hydrogen(H)
-Oxygen(O)

Question 4

Chemical elements that make up proteins

Answer 4

-Carbon(C)
-Hydrogen(H)
-Oxygen(O)
-Nitrogen(N)

Question 5

Polymers of glucose

Answer 5

-Starch
-Glycogen
-Cellulose

Question 6

Monomers of protein

Answer 6

Amino acids

Question 7

Monomers of fats/oils

Answer 7

-Glycerol
-Fatty acids

Question 8

Structure of a DNA molecule

Answer 8

-Two strands coiled together to form a double helix
-Each strand contains chemicals called bases
-Bonds between pairs of bases hold the strands together
-The bases always pair up in the same way(A with T, C with G)

Question 9

Colour change in Iodine solution

Answer 9

Orange-brown to blue-black

Question 10

Colour change in Benedict’s solution

Answer 10

Blue to brick-red

Question 11

Colour change in Biuret test

Answer 11

Blue to purple

Question 12

Colour change in Ethanol Emulsion test

Answer 12

Transparent to white(cloudy)

Question 13

Colour change in DCPIP

Answer 13

Blue to colourless

Question 14

Substance for Iodine solution

Answer 14

Starch

Question 15

Substance for Benedict’s solution

Answer 15

Reducing sugars(eg. glucose, fructose, lactose, maltose)

Question 16

Substance for Biuret test

Answer 16

Protein

Question 17

Substance for Ethanol Emulsion test

Answer 17

Fats and oils

Question 18

Substance for DCPIP test

Answer 18

Vitamin C

Question 19

Procedure for Iodine solution test

Answer 19

-Add iodine solution to substance
-Observe colour

Question 20

Procedure for Benedict’s solution test

Answer 20

-Add benedict’s solution to a substance(food)
-Heat substance
-Observe colour

Question 21

Procedure for Biuret test

Answer 21

-Add drops of biuret solution to food sample
-Observe colour

Question 22

Procedure for Ethanol Emulsion test

Answer 22

-Chop up food
-Shake it up with ethanol
-Pour ethanol(that was with food) into water(same volume as ethanol)
-Observe colour

Question 23

Procedure for DCPIP test

Answer 23

-Grind measured amount of fruit
-Add a measured amount of water
-Add DCPIP
-Shake well
-Observe colour