Ch 3 Part 1

Question 1

Alpha Helix

Answer 1

The spiral shape resulting from the coiling of a polypeptide in a protein’s secondary structure.

Question 2

Amino acid

Answer 2

An organic molecule containing a carboxyl group and an amino group; serves as the monomer of proteins.

Question 3

Amino group

Answer 3

In an organic molecule, a functional group consisting of a nitrogen atom bonded to two hydrogen atoms.

Question 4

Anabolic steroid

Answer 4

A synthetic variant of the male hormone testosterone that mimics some of its effects

Question 5

Carbohydrate

Answer 5

Member of the class of biological molecules consisting of simple single-monomer sugars (monosaccharides), two-monomer sugars (disaccharides), and other multiunit sugars (polysaccharides)

Question 6

Carbon skeleton

Answer 6

The chain of carbon atoms that forms the structural backbone of an organic molecule.

Question 7

Carbonyl group

Answer 7

In an organic molecule, a functional group consisting of a carbon atom linked by a double bond to an oxygen atom.

Question 8

Carboxyl group

Answer 8

In an organic molecule, a functional group consisting of an oxygen atom double-bonded to a carbon atom that is also bonded to a hydroxyl group.

Question 9

Cellulose

Answer 9

A large polysaccharide composed of many glucose monomers linked into cable-like fibrils that provide structural support in plant cell walls.

Question 10

Chitin

Answer 10

A structural polysaccharide found in many fungal cell walls and in the exoskeletons of arthropods

Question 11

Cholesterol

Answer 11

A steroid that is an important component of animal cell membranes and that acts as a precursor molecule for the synthesis of other steroids such as hormones.

Question 12

Dehydration reaction

Answer 12

A chemical process in which two molecules become covalently bonded to each other with the removal of a water molecule. Also called condensation.

Question 13

Denaturation

Answer 13

A process in which a protein unravels, losing its specific structure and hence function; can be caused by changes in pH or salt concentration or by high temperature. Also refers to the separation of the two strands of the DNA double helix, caused by similar factors.

Question 14

Deoxyribonucleic acid

Answer 14

A double-stranded helical nucleic acid molecule consisting of nucleotide monomers with deoxyribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and thymine (T). Capable of replicating, is an organism’s genetic material

Question 15

Disaccharide

Answer 15

A sugar molecule consisting of two monosaccharides linked by a dehydration reaction.

Question 16

Double helix

Answer 16

The form of native DNA, referring to its two adjacent polynucleotide strands wound into a spiral shape.

Question 17

Enzyme

Answer 17

A protein that serves as a biological catalyst, changing the rate of a chemical reaction without itself being changed into a different molecule in the process.

Question 18

Fat

Answer 18

A large lipid molecule made from an alcohol called glycerol and three fatty acids; a triglyceride. Most fats function as energy-storage molecules.

Question 19

Functional group

Answer 19

An assemblage of atoms commonly attached to the carbon skeletons of organic molecules and usually involved in chemical reactions.

Question 20

Gene

Answer 20

A discrete unit of hereditary information consisting of a specific nucleotide sequence. Most of the genes of a eukaryote are located in its chromosomal DNA; a few are carried by the DNA of mitochondria and chloroplasts

Question 21

Glycogen

Answer 21

An extensively branched polysaccharide of many glucose monomers; serves as an energy-storage molecule in liver and skeletal muscle cells; the animal equivalent of starch.

Question 22

Hydrocarbon

Answer 22

A chemical compound composed only of the elements carbon and hydrogen

Question 23

Hydrolysis

Answer 23

A chemical process in which polymers are broken down and degraded by the chemical addition of water molecules to the bonds linking their monomers.

Question 24

Hydrophilic

Answer 24

“Water-loving”; pertaining to polar, or charged, molecules (or parts of molecules) that are soluble in water.

Question 25

Hydrophobic

Answer 25

“Water-fearing”; pertaining to nonpolar molecules (or parts of molecules) that do not dissolve in water (insoluble).