Biology Chapter 12 Vocabulary

Question 1

Twisted-ladder shape of DNA, formed by two nucleotide strands twisted around each other

Answer 1

Double Helix

Question 2

Repeating subunit of chromatin fibers, consisting of DNA coiled around histones

Answer 2

Nucleosome

Question 3

Method of DNA replication in which parental strands separate, act as templates, and produce molecules of DNA with one parental DNA strand and one new DNA strand

Answer 3

Semiconservative replication

Question 4

Enzyme that catalyzes synthesis of new DNA molecules

Answer 4

DNA polymerase

Question 5

Short segment of DNA synthesized discontinuously in small segments in the 3’ to 5’ direction by DNA polymerase

Answer 5

Okazaki fragment

Question 6

Ribonucleic acid; guides protein synthesis

Answer 6

RNA

Question 7

Type of RNA that carries genetic information from DNA in the nucleus to direct protein synthesis in the cytoplasm

Answer 7

Messenger RNA

Question 8

Type of RNA that associates with proteins to form ribosomes

Answer 8

Ribosomal RNA

Question 9

Type of RNA that transports amino acids to the ribosomes

Answer 9

Transfer RNA

Question 10

Process in which mRNA is synthesized from the template DNA

Answer 10

Transcription

Question 11

Enzyme that regulates RNA synthesis

Answer 11

RNA polymerase

Question 12

In RNA processing, the intervening coding sequence missing from the final mRNA

Answer 12

Intron

Question 13

In RNA processing, the coding sequence that remains in the final mRNA

Answer 13

Exon

Question 14

Three-base code in DNA or RNA

Answer 14

Codon

Question 15

Process in which mRNA attaches to the ribosomes and a protein is assembled

Answer 15

Translation

Question 16

Ability of an organism to control which genes are transcribed in response to the environment

Answer 16

Gene regulation

Question 17

Section of DNA containing genes for proteins required for a specific metabolic pathway - consists of an operator, promoter, regulatory gene, and genes coding for proteins

Answer 17

Operon

Question 18

Permanent change in a cell’s DNA, ranging from changes in a single pair to deletions of large selections of chromosomes

Answer 18

Mutation

Question 19

Substance, such as a chemical, that causes mutations

Answer 19

Mutagen