Chapter 10 DNA: The Molecule of Heredity

Question 1

Adenine (A)

Answer 1

A nitrogenous base found in both DNA and RNA

Question 2

Base

Answer 2

(1) a substance capable of combining with and neutralizing H+ ions in a solution; a solution with a pH of more than 7; (2) in molecule genetrics, one of the nitrogen-containing, single or double ringed structures that distinguishes one nucleotide from another. In DNA, the bases are adenine, guanine, cytosine, and thymine.

Question 3

Complementary Base Pair

Answer 3

In nucleic acids, bases that pair by hydrogen bonding. In DNA, adenine is complementary to thymine and gaunine is complementary to cytosine; in RNA, adenine is complementary to uracil, and guanine to cytosine.

Question 4

Cytosine (C)

Answer 4

A nitrogenous base found in both DNA and RNA

Question 5

Deoxyribonucleic Acid (DNA)

Answer 5

A molecule composed of deoxyribose nucleotides; contains the genetic information of all cells.

Question 6

DNA Helicase

Answer 6

An enzyme that helps unwind the DNA double helix during DNA replication.

Question 7

DNA Ligase

Answer 7

An enzyme that joins the sugars and phosphates in a DNA strand to create a continous sugar-phosphate backbone.

Question 8

DNA Polymerase

Answer 8

An enzyme that bonds DNA nucleotides together into a continuous strand, using a preexisting strand as a template.

Question 9

DNA Replication

Answer 9

The copying of the double-stranded DNA molecule, producing two identical DNA double helices.

Question 10

Double Helix

Answer 10

The shape of the two-stranded DNA moleculel like a bladder twisted lengthwise into a corkscrew shape.

Question 11

Guanine (G)

Answer 11

A nitrogenous base found in both DNA and RNA

Question 12

Mutation

Answer 12

A change in the base sequence of DNA in a gene; normally refers to a genetic change significant enough to alter the appearance or function of the organism.

Question 13

Nucleotide

Answer 13

A subunit of which nucleic acids are composed; a phosphate group bonded to a sugar (deoxyribose in DNA), which is in turn bonded to a nitrogen-containing base (adenine, gaunine, cytosine, or thymine in DNA). Nucleotides are linked together, forming a strand of nucleic acid, as follows: Bonds between the phosphate of one nucleotide lnink to the sugar of the next nucleotide.

Question 14

Semiconservative Replication

Answer 14

The process of replication of the DNA double helix; the two DNA strands seperate, and each is used as a template for the synthesis of a compementary DNA strand.

Question 15

Strand

Answer 15

Single polymer of nucleotides; DNA is composed of two strands.

Question 16

Sugar-Phosphate Backbone

Answer 16

A major feature of DNA structure, formed by attaching the sugar of one nucleotide to the phosphate from the adjacent nucleotide in a DNA strand.

Question 17

Thymine (T)

Answer 17

A nitrogenous base found only in DNA