Show:
Atoms & Basic Chemistry
Types of Chemical Bonds
The Properties of Water
Carbon Macromolecules
Enzymes & Reactions
100

Atoms are composed of...

protons, neutrons, and electrons

100

Ionic bonds form between molecules that have

opposite charges.

100

A molecule, like water, that has a partial positive charge on one side....

polar molecule

100

Which of the following is NOT an organic macromolecule? a. carbohydrate b. ice c. lipid d. nucleic acid

ice

100

An enzyme a. is not used up when catalyzing a reaction. b. lowers the activation energy of a reaction. c. bonds with a substrate molecule at the enzyme's active site. d. all of the above.

all of the above

200

The electrons of an atom a. are found in the nucleus along with the protons. b. occupy the space surrounding the nucleus. c. have a positive charge. d. are attached to the positive charge of neutrons.

occupy the space surrounding the nucleus.

200

The bond formed when two atoms share a pair of electrons is called a(n)

covalent bond

200

When placed in the same container, oil and water do not mix because....

water is polar and oil is nonpolar

200

All organic compounds contain the element....

carbon

200

Enzymes a. are able to heat up molecules so that they can react. b. always provide carbon dioxide for chemical reactions. c. are biological catalysts. d. absorb excess heat so that reactions occur at low temperatures.

are biological catalysts

300

The smallest particle of matter that can retain the chemical properties of carbon is a(n)....

carbon atom.

300

Weak attractions between polar molecules are ______________ bonds.

hydrogen

300

Acidic solutions have a pH that is what on the pH scale...

less than 7

300

Which of the following organic molecules are classified as carbohydrates?

sugars

300

The starting materials for chemical reactions are called _________________, while the new substances that are formed are called _______________.

reactants; products

400

A substance that is composed of only one type of atom is called a(n)

element.

400
The attraction that causes water to bond together to form drops is __________________.
cohesion
400

Due to the polarity of water, compounds that dissolve test in water contain...

both ionic bonds and polar bonds

400
Long chains of nucleotides are called _____________ ______.
nucleic acids
400

The energy needed to start a chemical reaction is called ______________ ___________.

activation energy

500

A(n) _______________ is a group of atoms held together by covalent bonds.

molecule

500
The portion of an enzyme molecule into which a specific substrate bonds is called the __________ _______.
active site
500
Water heats and cools more ____________ than other liquids.
slowly
500
Lipids are _______________ molecules because they have no negative and positive poles.
nonpolar
500

The molecule on which an enzyme acts is called the ________________.

substrate