Chapter 3

Question 1

Organic molecules

Answer 1

Carbon-containing molecules that are found in all forms of life

Question 2

4 major classes of organic molecules

Answer 2

• Lipids
• Carbohydrates
• Proteins
• Nucleic acids

Question 3

Of the 4 major classes of organic molecules, which of the three are macromolecules?

Answer 3

Carbohydrates, proteins, and nucleic acids

Question 4

Organic Chemistry

Answer 4

The science of carbon-containing molecules

Question 5

Condensation reaction

Answer 5

A chemical reaction that involves two or more molecules combining into a larger molecule by covalent bonding, with the loss of a small molecule

Question 6

Dehydration reaction

Answer 6

A type of condensation reaction, where a water molecule is lost in the linkage process

Question 7

Hydrolysis reaction

Answer 7

The process of breaking down a polymer, in which a water molecule is added back each time a monomer is released

Question 8

How many shells of electrons does carbon have?

Answer 8

Two

Question 9

Stereoisomers

Answer 9

Isomers that have identical bonding relationships but a different spatial arrangement of atoms

Question 10

Carbohydrates such as ____, ____ and ____ are polymers of glucose.

Answer 10

cellulose; glycogen; starch

Question 11

What are the functions of fats in living organisms?

Answer 11

• Support cushion for organs
• Energy storage
• Insulation

Question 12

____ is a type of lipid that consists of a glycerol molecule attached to one ____ group and two ____ ____.

Answer 12

Phospholipid; phosphate; fatty acids

Question 13

The polar hydrophilic region of a phospholipid molecule is composed of…

Answer 13

Glycerol backbone, phosphate group, and the charged nitrogen-containing region

Question 14

The molecular structure of wax

Answer 14

A long hydrocarbon chain resembling a fatty acid attached by its carbonyl group to another long hydrocarbon chain

Question 15

The tertiary structure of a polypeptide is predominantly determined by its ____ structure

Answer 15

Primary

Question 16

For polypeptide chains, hydrogen bonds can form ____ a polypeptide and ____ different polypeptide chains

Answer 16

Within; between

Question 17

Disulfide bridges are covalent bonds between ____ groups of cysteine side chains

Answer 17

Sulfhydryl (-SH)

Question 18

Like hydrogen bonding in polypeptides, disulfide bonds can form between two cysteines located ____ the polypeptide chain or in ____ chains

Answer 18

Between; different

Question 19

When a protein is denatured, ____, ____ and ____ bonds are broken, but the ____ bonds still remain intact for linking adjacent amino acids

Answer 19

Disulfide; Hydrogen; Ionic; peptide

Question 20

Structural isomers

Answer 20

Isomers with the same atoms but with different bonding relationships

Question 21

Cis-trans isomers

Answer 21

Isomers have identical bonding relationships but hydrogen atoms are positioned differently around a double bond

Question 22

Enantiomers

Answer 22

Isomers have identical bonding relationships but the atoms are positioned differently, resulting in mirror images

Question 23

What are isomers?

Answer 23

Molecules that have identical molecular formulas but different structures

Question 24

What are isotopes?

Answer 24

Forms of the same atom that differ in the number of neutrons they contain

Question 25

Triglycerides (fats) are composed of…

Answer 25

Glycerol covalently bound to three fatty acids

Question 26

The composition of a phospholipid molecule

Answer 26

A head that is polar and hydrophilic, and two tails that are non-polar and hydrophobic

Question 27

3 major structural components of an amino acid

Answer 27

- Amino group (single nitrogen atom bonded to 2 hydrogen atoms) - Nitrogenous base (adenine, cytosine, guanine, thymine and uracil) - Carboxyl group (combination of 2 functional groups attached to a single carbon atom, namely, hydroxyl (single-bonded OH) and carbonyl (double bonded O) groups)

Question 28

What are the bonds and interactions that contributes directly to a protein’s tertiary structure?

Answer 28

- Ionic bonds - Van der Waals forces - Disulfide bonds - Hydrogen bonds - Hydrophobic effect

Question 29

The chemical structure of a typical amino acid found in a protein

Answer 29

A central carbon atom bounded to an amino group, carboxyl group, a side chain, and a hydrogen atom

Question 30

Proteins are made by ____ reactions

Answer 30

Dehydration

Question 31

During a dehydration reaction, ____ bond forms between two sugars, while ____ bond forms between amino acids

Answer 31

Glycosidic; peptide

Question 32

In a peptide bond, which parts of the two amino acids are joined together?

Answer 32

The amino group of one and the carboxyl group of the other

Question 33

Primary structure of a protein

Answer 33

The sequence of amino acids in a polypeptide

Question 34

Secondary structure of a protein

Answer 34

The repeating pattern of folding between regions

Question 35

Tertiary structure of a protein

Answer 35

The three-dimensional shape of a single polypeptide chain

Question 36

Quaternary structure of a protein

Answer 36

The interactions between two or more polypeptide chains

Question 37

Ribozymes

Answer 37

RNA enzyme that catalyzes a chemical reaction “Catalytic RNAs that cut things, make things, and do odd and useful jobs”