Chapters 2,3, and 4

When two atoms are equally electronegative, they will interact to form

nonpolar covalent bonds.

Which of the following is primarily responsible for the unique chemical properties of each element?

Each element has a unique number of neutrons

In what way are elements in the same column of the periodic table the same?

They have the same number of electrons in their valence shell.

What results from an unequal sharing of electrons between atoms?

A non polar covalent bond

In an aqueous solution, water molecules associate with one another through

Hydrogen bond

The chemical behavior of an atom depends primarily upon which of the following?

the number of electrons in the valence shell

A covalent chemical bond is one in which

outer-shell electrons of two atoms are shared so as to occupy the outer electron shells of both atoms.

What is the difference between covalent bonds and ionic bonds?

Covalent bonds involve the sharing of pairs of electrons between atoms; ionic bonds involve the sharing of single electrons between atoms.

How many electron pairs does carbon share in order to complete its valence shell?

4

Which of the following effects is produced by the high surface tension of water?

A water strider can walk across the surface of a small pond.

Which of the following will dissolve in water?

organic molecules with hydroxyl groups

Hydrophobic substances such as vegetable oil are

nonpolar substances that repel water molecules.

Which of the following statements about buffer solutions is true?

They maintain a relatively constant pH when either acids or bases are added to them.

Which of the following chemical equations describes a hydrolysis reaction?

disaccharide + H20 monosaccharide + monosaccharide

Testosterone and estradiol are male and female sex hormones, respectively, in many

Testosterone and estradiol are structural isomers but have the same molecular formula.

Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified?

as a disaccharide

There are 20 different amino acids. What makes one amino acid different from another?

different side chains (R groups) attached to an a carbon

One advantage of light microscopy over transmission electron microscopy is that

light microscopy allows one to view dynamic processes in living cells.

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?

Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers.

Biologists commonly use cell fractionation to

isolate organelles to examine their biological functions.

Which of the following may be found in eukaryotic cells, but not in bacteria?

Endoplasmic reticulum

Which of the following will be found in nearly all eukaryotic cells?

Mitochondria

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?

Proteins

Some key innovations in the evolution of eukaryotes from a prokaryotic ancestor are membrane-bound organelles. Which of the following organelles or features is likely to be a common component shared by both eukaryotic cells and their prokaryotic ancestors?

Ribosomes