Chapter 4: Carbon and the Molecular Diversity of Life

Question 1

organic chemistry

Answer 1

the study of carbon compounds (organic compounds)

Question 2

Stanley Miller

Answer 2

• classic experiment demonstrated the abiotic synthesis of organic compounds
• experiments support the idea that abiotic synthesis of organic compounds, perhaps near volcanoes, could have been a stage in the origin of life

Question 3

electron configuration

Answer 3

• the key to an atom’s chemical characteristics
• determines the kinds and number of bonds an atom will form with other atoms

Question 4

carbon

Answer 4

can form four covalent bonds with a variety of atoms due to its four valence electrons

Question 5

valence

Answer 5

• the bonding capacity of a given atom
• the number of covalent bonds that an atom can form, which usually equals the number of unpaired electrons in its outermost (valence) shell

Question 6

hydrogen, oxygen, nitrogen

Answer 6

the most frequent bonding partners of carbon

Question 7

carbon chains

Answer 7

• form the skeletons of most organic molecules
• vary in length and shape

Question 8

hydrocarbon

Answer 8

an organic molecule consisting only of carbon and hydrogen

Question 9

isomer

Answer 9

one of two or more compounds that have the same numbers of atoms of the same elements but different structures and hence different properties

Question 10

structural isomer

Answer 10

one of two or more compounds that have the same molecular formula but differ in the covalent arrangements of their atoms

Question 11

cis-trans isomer

Answer 11

• one of several compounds that have the same molecular formula and covalent bonds between atoms but differ in the spatial arrangements of their atoms owing to the inflexibility of double bonds
• formerly called a geometric isomer

Question 12

enantiomer

Answer 12

one of two compounds that are mirror images of each other and that differ in shape due to the presence of an asymmetric carbon

Question 13

functional group

Answer 13

a specific configuration of atoms commonly attached to the carbon skeletons of organic molecules and involved in chemical reactions

Question 14

seven functional groups

Answer 14

• Hydroxyl group
• Carbonyl group
• Carboxyl group
• Amino group
• Sulfhydryl group
• Phosphate group
• Methyl group

Question 15

Hydroxyl group

Answer 15

• a chemical group consisting of an oxygen atom joined to a hydrogen atom
• molecules possessing this group are soluble in water and are called alcohols
• -OH

Question 16

Carbonyl group

Answer 16

a chemical group present in aldehydes and ketones and consisting of a carbon atom double-bonded to an oxygen atom

Question 17

Carboxyl group

Answer 17

a chemical group present in organic acids and consisting of a single carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group

Question 18

Amino group

Answer 18

• a chemical group consisting of a nitrogen atom bonded to two hydrogen atoms
• can act as a base in solution, accepting a hydrogen ion and acquiring a charge of 1+

Question 19

Sulfhydryl group

Answer 19

a chemical group consisting of a sulfur atom bonded to a hydrogen atom
- -SH

Question 20

Phosphate group

Answer 20

• a chemical group consisting of a phosphorus atom bonded to four oxygen atoms
• important in energy transfer

Question 21

Methyl group

Answer 21

• a chemical group consisting of a carbon bonded to three hydrogen atoms
• may be attached to a carbon or to a different atom
• only hydrophobic group

Question 22

adenosine triphosphate (atp)

Answer 22

• an adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed
• this energy is used to drive endergonic reactions in cells