Chapter 4: Biological Molecules

Which simple molecules are the basic units of protein?

• amino acids

• fatty acids

• glucose

• vitamins

Tags

NGSS.HS-LS1-6

Small molecules are used as the basic units in the synthesis of large food molecules.

Which statement is correct?

• Amino acids are basic units of carbohydrates.

• Fatty acids are basic units of glycogen.

• Glycerol is a basic unit of oils.

• Simple sugar is a basic unit of protein.

Tags

NGSS.HS-LS1-6

Which nutrient produces a purple colour when mixed with Biuret solution?

• fat

• protein

• reducing sugar

• starch

The diagram shows two food tests carried out on solution X.

Which nutrients are present in solution X?

• protein and starch

• protein and sugar

• starch and fat

• starch and sugar

Tags

NGSS.HS-PS1-2

A student set up a test-tube containing starch, water and amylase.

How could the student test whether the amylase had digested all the starch?

• Add Biuret solution.

• Add dilute hydrochloric acid.

• Add iodine solution.

• Weigh the test-tubes and contents before and after the experiment.

When solution X is tested with iodine solution, a blue-black colour is observed.

A different solution, Y, is added to a new sample of solution X and the mixture is shaken and left for 30 minutes at 40°C.

When tested with iodine solution again, an orange-brown colour is observed. What are solutions X and Y?

• X=maltose, Y=amylase

• X=maltose, Y=lipase

• X=starch, Y=amylase

• X=starch, Y=lipase

Tags

NGSS.HS-PS1-2

Water is a good solvent.

What does this mean?

• It dissolves well in many other substances.

• It flows easily through vessels.

• It is permeable to gases.

• Many substances dissolve well in it.

Tags

NGSS.MS-ESS2-4

Which elements do carbohydrates contain?

• carbon, hydrogen and oxygen

• carbon, hydrogen and sulphur

• carbon, nitrogen and oxygen

• carbon, nitrogen and sulphur

Tags

NGSS.HS-LS1-6

Which of the following is NOT a reducing sugar?

• lactose

• sucrose

• maltose

• glucose

Which of the following the example of monosaccharides?

• starch

• sucrose

• glucose

• cellulose