Biology Unit 2 Review

Which describes a substance that is made up of only one kind of atom and cannot be broken down by chemical reactions?

• element

• electron

• carbohydrate

• molecule

Which substance is an example of a carbohydrate?

• DNA

• wax

• enzyme

• sugar

RNA is an example of a(n)

• lipid.

• nucleic acid.

• carbohydrate.

• protein.

What organic molecule stores the greatest amount of energy? 

• carbohydrate.

• nucleic acid.

• lipid.

• protein.

Which formula is an example of an organic compound?

• NO₂

• C₆H₁₂O₆

• O₂

• H₂O

Tags

NGSS.MS-PS1-1

Proteins are long molecules that are built from various combinations of 

• nucleotides.

• lipids.

• amino acids.

• carbohydrates

Tags

NGSS.MS-LS3-1

An animal's stomach contains enzymes that break down food into smaller molecules that the animal's cells can use.  Enzymes perform this function by

• increasing the temperature.

• changing the ionic concentration.

• lowering the pH.

• lowering the activation energy.

Tags

NGSS.MS-LS1-7

A spider is able to walk on water without sinking due to water's 

• surface tension.

• specific heat

• ionic concentration.

• solvency.

A substance with a pH of 6 is called

• a base.

• an acid.

• both an acid and a base.

• neither an acid nor a base.

Isotopes are atoms of the same element with the same number of protons and

• the same number of neutrons.

• a different number of neutrons.

• a different number of molecules.

• a different number of electrons.