Chapter 2

Question 1

neutrons

Answer 1

no charge

Question 2

protons

Answer 2

positive charge

Question 3

electrons

Answer 3

negative charge

Question 4

covalent bonds

Answer 4

valence electrons are shared, low electronegativity difference

Question 5

molecule

Answer 5

2 or more atoms held together by covalent bonds

Question 6

electronegativity

Answer 6

attraction for electrons

Question 7

nonpolar covalent bond

Answer 7

electrons are shared equally

Question 8

polar covalent bond

Answer 8

one atom is more electronegative, and atoms do not share electrons equally, creating partial charges

Question 9

ionic bonds

Answer 9

electrons are transferred, forms cation (positive) and anion (negative)

Question 10

hydrogen bonds

Answer 10

weak bonds created by hydrogen’s charge attraction to oxygen in separate water molecules

Question 11

acidic solutions

Answer 11

pH less than 7

Question 12

basic solutions

Answer 12

pH greater than 7

Question 13

carbon

Answer 13

forms large, complex, and varied molecules, and organic compounds

Question 14

dehydration reaction

Answer 14

two monomers bond together through the loss of a water molecule

Question 15

hydrolysis

Answer 15

polymers are disassembled by the addition of a water molecule

Question 16

enzymes

Answer 16

speed up chemical reactions

Question 17

monosaccharides

Answer 17

molecular formulas that are multiples of CH2O

Question 18

lipids

Answer 18

hydrophobic because consist mostly of hydrocarbons (which form nonpolar covalent bonds) and thus do not form true polymers

Question 19

saturated fats

Answer 19

single bonds, saturated by hydrogens, solid at room temperature; most animal fats

Question 20

unsaturated fats

Answer 20

contains double bonds, can’t pack as closely together, fewer hydrogens, liquid at room temperature; usually plant and fish fats

Question 21

phospholipid

Answer 21

major constituents of cell membranes; two fatty acids (hydrophobic) and a phosphate group (hydrophilic) attached to glycerol

Question 22

proteins

Answer 22

more than 50% of dry mass of most cells, made of amino acids, functions include defense, storage, transport, cellular communication, movement, and structural support

Question 23

primary structure

Answer 23

linear chain of amino acids

Question 24

secondary structure

Answer 24

regions stabilized by hydrogen bonds between atoms of the polypeptide backbone

Question 25

tertiary structure

Answer 25

3d shape stabilized by interactions between side chains

Question 26

quaternary structure

Answer 26

some proteins only, association of 2 or more polypeptides

Question 27

gene

Answer 27

made of DNA, programs amino acid sequence of a polypeptide

Question 28

DNA

Answer 28

nucleic acid made of nucleotides, sugar is deoxyribose

Question 29

RNA

Answer 29

sugar is ribose

Question 30

double helix

Answer 30

two polynucleotides spiraling around an imaginary axis, antiparallel in DNA

Question 31

complementary base pairing

Answer 31

nitrogenous bases in DNA pair up and form hydrogen bonds: adenine (A) always with thymine (T) and guanine (G) always with cytosine (C)