chapter 2

Question 1

DNA

Answer 1

is described like a double helix, organized into 46 chromosomes, attached by hydrogen bonds

Question 2

elements found in the body

Answer 2

nitrogen, hydrogen, carbon, oxygen

Question 3

isotopes

Answer 3

forms of the same element that have an equal number of protons but a different number of neutrons, unstable, emit radioactive waves, isotopes DONATE

Question 4

PET scan

Answer 4

uses isotopes, highlights areas in the body that are high in glucose to show cancer,

Question 5

electron shells

Answer 5

must fill the outermost shell to be considered stable, all elements make an effort to reach stability

Question 6

types of chemical bonding

Answer 6

ionic, covalent, hydrogen

Question 7

ionic bonds

Answer 7

when an element donates an electron to fill the outer shell of another element, attraction of many sodium and chloride ions result in the formation of a large group called a crystal

Question 8

covalent bonding

Answer 8

sharing of pairs of electrons between atoms, goal is for the outer shell to be filled so they reach stability

Question 9

covalent bonds in water

Answer 9

water forms a covalent bond with the hydrogen and oxygen atoms, the oxygen atom “wants” the electrons more than the hydrogen atoms do

Question 10

hydrogen bonds

Answer 10

hydrogen bonds are weak, they are indicated with a dotted line rather than solid, between a weak negative and positive charge

Question 11

enzymes

Answer 11

substrate -> enzyme-substrate complex-> products, reduce activation energy so increasing the rate of reaction

Question 12

how enzymes help

Answer 12

less energy is needed for a reaction to begin

Question 13

monomers

Answer 13

the basic units for building larger molecules, form polymers

Question 14

polymers

Answer 14

two or more chemically bonded monomers

Question 15

dehydration synthesis

Answer 15

two monomers are covalently bonded in a reaction in which one gives up a hydroxyl group and the other a hydrogen atom. a molecule of water is released as a byproduct

Question 16

hydrolysis

Answer 16

the covalent bond between two monomers is split by the addition of a hydrogen atom to one and a hydroxyl group to the other, this requires the gaining of one molecule of water

Question 17

dissociation of sodium chloride in water

Answer 17

the crystals of sodium chloride dissociate NOT into molecules of NaCl, but into Na+ cations and Cl- anions, each completely surrounded by water molecules

Question 18

acids

Answer 18

dissociates into hydrogen ions and anions. nearly every molecule of a strong acid dissociates producing a high concentration of H+

Question 19

bases

Answer 19

dissociates into hydroxyl ions and cations, nearly every molecule of a strong base dissociates producing a high concentration of OH-

Question 20

types of macromolecules

Answer 20

carbohydrates, lipids, proteins, nucleic acids

Question 20

types of monosaccharides

Answer 20

glucose, fructose, galactose, deoxyribose, ribose

Question 20

how disaccharides form

Answer 20

dehydration synthesis to form glycosidic bonds

Question 20

types of polysaccharides

Answer 20

starch, glycogen, cellulose

Question 21

types of disaccharides

Answer 21

sucrose, lactose, maltose

Question 22

what are triglycerides

Answer 22

three fatty acid chains are bound to glycerol by dehydration synthesis

Question 23

what are triglycerides composed of

Answer 23

glycerol attached to three fatty acids via dehydration synthesis, glycerol gives up a hydrogen atom, and the carboxyl groups on the fatty acids each give up a hydroxyl group

Question 24

what do saturated fatty acid chains look like

Answer 24

straight

Question 25

what do unsaturated fatty acid chains look like

Answer 25

kinked

Question 26

phospholipids

Answer 26

composed of two fatty acids, glycerol, and a phosphate group

Question 27

sterols

Answer 27

ring- shaped lipids

Question 28

prostaglandins

Answer 28

derived from unsaturated fatty acids. PGE2 includes hydroxyl and carboxyl groups

Question 29

amino acids

Answer 29

central carbon atom bonded to hydrogen atoms, amide group, carboxyl group, R- group (20 naturally occurring)

Question 30

peptide bonds

Answer 30

different amino acids join together to form peptides, polypeptides, or proteins via dehydration synthesis. The bonds between amino acids are peptide bonds

Question 31

protein primary structure

Answer 31

the sequence of amino acids that make up a polypeptide chain

Question 32

protein secondary structure

Answer 32

can take form of an alpha- helix or beta- pleated sheet, is maintained by hydrogen bonds between amino acids in different regions of the original polypeptide strand

Question 33

protein tertiary structure

Answer 33

occurs as a result of further folding and bonding of the secondary structure

Question 34

protein quaternary structure

Answer 34

occurs as a result of interactions between two or more tertiary subunits

Question 35

nucleotides building blocks

Answer 35

one or more phosphate groups, a pentose sugar, and a nitrogen containing base

Question 36

ATP

Answer 36

a derivative of the nucleotide adenine, the energy currency of all cells

Question 37

mass number

Answer 37

the weight of neutrons and protons

Question 38

protons and electrons are ______ in number

Answer 38

equal

Question 39

polar

Answer 39

charged

Question 40

non-polar

Answer 40

no charge