Chapter 2 Review Assignment

The essential elements that make up the key molecules in living organisms are carbon, hydrogen, nitrogen, oxygen, sulfur, and ________.

• phosphorus

• calcium

• magnesium

• potassium

Which of the following is NOT one of the macromolecules found in living organisms?

• Carbohydrates

• Nucleic acids

• Proteins

• Vitamins

Biological macromolecules are built from smaller organic units called ________.

• monomers

• polymers

• ions

• atoms

The four key types of molecules in living organisms mentioned are carbohydrates, nucleic acids, proteins, and ________.

• lipids

• minerals

• vitamins

• salts

What is matter? Matter occupies ______ and has ______.

• space; mass

• energy; weight

• air; volume

• light; density

All matter is composed of ______, substances that cannot be broken down or transformed chemically into other substances.

• elements

• compounds

• mixtures

• molecules

Elements are ______ that consist of only one type of atom.

• pure substances

• mixtures

• compounds

• solutions

Which of the following statements is TRUE about elements? Select the correct option.

• Elements can be broken down into simpler substances by chemical means.

• Elements are composed of only one type of atom.

• Elements are mixtures of different atoms.

• Elements are always found as compounds. atmosphere isn't made of only one kind of element, and it is not always found as compounds in its elemental (non-compounded) form, either

Refer to the diagram showing atoms, molecules, compounds, and mixtures. Which box represents a mixture of elements and a compound?

• First box

• Second box

• Third box

• Fourth box

What are the three main subatomic particles that make up an atom?

• Protons, neutrons, and electrons

• Protons, photons, and electrons

• Neutrons, electrons, and positrons

• Protons, neutrons, and photons