Proteins and Nucleic Acids

Question 1

Describe protein denaturation and the conditions that bring it about

Answer 1

When the pH, salinity, temperature or other aspects of a protein’s environment are altered, the weak chemical bonds and interactions within a protein may be destroyed, causing the protein to unravel and lose its native shape, rendering it biologically inactive

Question 2

What are the three components of a nucleotide?

Answer 2

Nitrogenous base, a pentose sugar, and a phosphate

Question 3

What are the structural differences between ribonucleotides and deoxyribonucleotides?

Answer 3

Ribonucleotides have a ribose sugar (hydroxyl group at the second carbon) and uracil as a possible nitrogenous base; deoxyribonucleotides have a deoxyribose sugar (hydrogen atom at the second carbon) and thymine as a possible nitrogenous base

Question 4

Sketch and label the parts of a helical DNA

Answer 4

[Sugar-phosphate backbone, nitrogenous base pairs, hydrogen bonds]

Question 5

Describe the relationship between DNA, RNA, and protein

Answer 5

DNA contains protein-encoding information, RNA uses that information to enable to the cell to synthesize a protein

Question 6

Central Dogma

Answer 6

DNA replicates itself and is used to create RNA, RNA is used to create proteins

Question 7

Sketch a model of ATP

Answer 7

[Triphosphate group, ribose, and adenine]

Question 8

Enzymes

Answer 8

Specialized macromolecules (usually proteins) that speed up chemical reactions

Question 9

Hydrolysis

Answer 9

Process that reverses a dehydration reaction by disassembling polymers into monomers

Question 10

Dehydration Reaction

Answer 10

Condensation reaction (connects a monomer to another monomer or a polymer) that involves a water molecule being lost

Question 11

Receptor Proteins

Answer 11

Allow cell to respond to chemical stimuli

Question 12

Structural Proteins

Answer 12

Support the cell

Question 13

Contractile and Motor Proteins

Answer 13

Allow for movement within cells

Question 14

Transcription Factors

Answer 14

Proteins that control the rate of transcription of genetic information from DNA to mRNA by binding to a specific DNA sequence

Question 15

Protein Structure

Answer 15

Three-dimensional architecture of proteins

Question 16

Primary Protein Structure

Answer 16

A protein’s sequence of amino acids

Question 17

Secondary Protein Structure

Answer 17

Coils and folds in polypeptide chain that are the result of hydrogen bonds between the repeating constituents of the polypeptide backbone

Question 18

Tertiary Protein Structure

Answer 18

The overall shape of a polypeptide resulting from interactions between the side chains of the various amino acids

Question 19

Quaternary Protein Structure

Answer 19

The overall protein structure that results from the aggregation of two or more polypeptide chains

Question 20

Gene

Answer 20

Discrete unit of inheritance consisting of DNA

Question 21

Nucleic Acids

Answer 21

Polymers made of monomers called nucleotides

Question 22

Deoxyribonucleic Acid

Answer 22

Type of nucleic acid that provides directions for its own replication and also directs RNA synthesis

Question 23

Ribonucleic Acid

Answer 23

Type of nucleic acid that controls protein synthesis

Question 24

Nucleotides

Answer 24

Composed of a five-carbon sugar (pentose), a nitrogen containing (nitrogenous) base, and one to three phosphate groups

Question 25

Pyrimidine

Answer 25

Family of nitrogenous bases containing a six-membered ring of carbon and nitrogen atoms (cytosine, thymine, and uracil)

Question 26

Purine

Answer 26

Family of nitrogenous bases containing a six membered ring fused to a five-member ring (adenine and guanine)

Question 27

Double Helix

Answer 27

The form taken by the two polynucleotides (strands) that wind around an imaginary axis to form a DNA molecule

Question 28

Antiparallel

Answer 28

The arrangement of the two sugar-phosphate backbones which run in opposite 5’ → 3’ directions from each other