Biochem 1: Intro

Question 1

atomic structure

• electrons
• protons
• neutrons

Answer 1

electrons: negligible mass, negative charge
protons: have mass, positive charge
neutrons: have mass, no charge

Question 2

all matter is composed of

Answer 2

atoms

Question 3

covalent bonds

Answer 3

when two atoms share one or more pairs of electrons

Question 4

chemical bonds are

Answer 4

an attractive force that links two atoms together in a molecule

Question 5

electronegativity

Answer 5

sharing of electrons in a covalent

Question 6

electronegativity depends on:

Answer 6

the number of protons and the distance between the nucleus and electrons

Question 7

nonpolar covalent bonds

Answer 7

electrons are shared equally (atoms have similar electronegativity)

Question 8

polar covalent bonds

Answer 8

electrons are drawn to one nucleus more than the other because that atom has greater electronegativity

Question 9

ionic bonds

Answer 9

when one atom is much more electronegative than the other, a complete transfer of electrons may occur
(this results in two ions with full outer shells)

Question 10

ions in a solid

Answer 10

ions are close together and the ionic attractions are strong

Question 11

ions in water

Answer 11

the ions are far apart and the attraction is much weaker

Question 12

ionic attractions in living cells are much _____ than covalent bonds

Answer 12

weaker

Question 13

hydrogen bonds form

Answer 13

within or between molecules with polar covalent bonds

Question 14

what are hydrogen bonds

Answer 14

weak electrical attractions between a partially negatively charged atom and a partially positively charged atom

Question 15

hydrogen bonds are weaker than

Answer 15

weaker than most ionic bonds and much weaker than covalent bonds

Question 16

influences of hydrogen bonds

Answer 16

have considerable strength and greatly influence the structure and properties of substances

Question 17

what are ions? and what are cations and anions

Answer 17

ions are electrically charged particles formed when atoms lose or gain electrons

• cations are positive
• anions are negative

Question 18

ionic attraction bonds are formed by

Answer 18

electrical attraction of positive and negative ions

Question 19

monomer of protein

Answer 19

amino acid

Question 20

monomer of nucleic acids

Answer 20

nucleotides

Question 21

monomer of polyaccharides

Answer 21

monosaccharides

Question 22

monomers of lipids

Answer 22

glycerol and 3 fatty acids

Question 23

what are functional groups

Answer 23

bond to carbon skeletons and are responsible for most of the chemical properties of a particular organic compound