carbohydrates, lipids and proteins

Question 1

what elements do carbohydrate molecules contain

Answer 1

carbon, hydrogen, oxygen

Question 2

starch and glycogen…

Answer 2

are large complex carbohydrates which are made up of many smaller units joined together in a long chain

Question 3

what elements do proteins contain

Answer 3

CARBON, HYDROGEN, OXYGEN ATOMS

Question 3

what are lipids built from

Answer 3

fatty acids and glycerol

Question 4

what are proteins made of

Answer 4

long chains of amino acids

Question 5

what elements do lipids contain

Answer 5

carbon, hydrogen, oxygen

Question 5

benedicts test for testing…

Answer 5

glucose

Question 6

iodine solution test for testing…

Answer 6

starch

Question 7

biuret test for testing for

Answer 7

proteins

Question 7

sudan III test for testing for

Answer 7

lipids

Question 7

benedics solution:

Answer 7

prepare food sample and transfer 5 cm 3 to test tube
prepare a water bath so that its set to 75 degrees.
add 10 drops of benedics solution to test tube using a pipette
place the test tube in the water bath using a test tube holder and leave it in there for 5 mins
if the food sample contains glucose, the solution will change to blue. it will become green or yellow in low concentrations of glucose, or brick red in high concentrations

Question 8

iodine solution:

Answer 8

make a food sample and transfer 5cm 3 of your sample to a test tube
add few drops of iodine solution and gently shake the tube to mix
if sample contains starch the colour change from browny orange to black or bluey black

Question 9

biuret test:

Answer 9

prepare sample of food and transfer 2cm 3 of your sample to a test tube.
add 2 cm 3 of biuret solution to the sample and mix contents of test tube by gently shaking it
if food sample contains protein. solution will change from blue to pink or purple