Biology Chapter 2 Pretest

The three particles that make up an atom are:

• protons, neutrons and isotopes

• neutrons, isotopes and electrons

• positives, negatives and electrons

• protons, neutrons and electrons

Which of the following terms describes a substance formed by the combination of two or more elements in definite proportions?

• compound

• nucleus

• isotope

• enzyme

A covalent bond is formed as a result of:

• transferring electrons

• sharing electrons

• transferring protons

• sharing protons

A substance that speeds up the rate of a chemical reaction is called a (an):

• catalyst

• molecule

• lipid

• element

A chemical bond formed by the transfer of electrons is a (an) __________ bond.

• covalent

• van der Waahl

• ionic

• hydrogen

Which one of the following is not one of the four groups of organic compounds that make up organisms?

• carbohydrates

• amino acids

• lipids

• proteins

DNA and RNA are examples of:

• proteins

• amino acids

• nucleic acids

• peptides

A substance with a pH of 9 is:

• an acid

• a base

• a solvent

• neutral

Carbohydrates are used by plants and animals for:

• homeostasis

• storage

• enzymes

• energy

Which one of the following groups represents the four most important elements in organisms?

• CHOP

• CHON

• CaHON

• NOPS