chapter 8 terminology

Question 1

genetics

Answer 1

the science of heredity, includes the study of what genes are, how they carry information, how they are replicated and passed to subsequent organisms, and how the expression of their information within an organism determines the particular characteristics of that organism

Question 2

genome

Answer 2

the genetic information in a cell

Question 3

chromosomes

Answer 3

structures containing DNA that physically carry hereditary information, contain the genes

Question 4

genes

Answer 4

segments of DNA that code for functional products

Question 5

genetic code

Answer 5

the set of rules that determines how a nucleotide sequence is converted into the amino acid sequence of a protein

Question 6

genotype

Answer 6

the genetic makeup of an organism, the information that codes for all the particular characteristics of the organism

Question 7

phenotype

Answer 7

the expressed properties, manifestation of the genotype

Question 8

genomics

Answer 8

the sequencing and molecular characterization of genomes

Question 9

DNA Polymerase

Answer 9

an enzyme that synthesizes DNA; proofreads and repairs DNA

Question 10

replication

Answer 10

one “parental” double-stranded DNA molecule is converted into 2 “daughter” molecules

Question 11

replica plating

Answer 11

microbiological technique in which one or more secondary Petri plates containing different solid selective growth media (lacking nutrients or containing chemical growth inhibitors such as antibiotics) are inoculated with the same colonies of microorganisms from a primary plate

Question 12

transcription

Answer 12

the synthesis of a complementary strand of RNA from a DNA template

Question 13

messenger RNA

Answer 13

carries the coded information for making specific proteins from DNA to ribosomes

Question 14

promoter

Answer 14

the starting site on a DNA strand for transcription of RNA by RNA Polymerase

Question 15

terminator

Answer 15

the site on a DNA strand at which transcription ends

Question 16

translation

Answer 16

the use of mRNA as a template in the synthesis of protein

Question 17

codons

Answer 17

a sequence of 3 nucleotides in mRNA that specifies the insertion of an amino acid into a polypeptide

Question 18

sense codons

Answer 18

a codon that codes for an amino acid

Question 19

nonsense codons

Answer 19

a codon that does not encode any amino acid

Question 20

transfer RNA

Answer 20

the type of RNA molecule that brings amino acids to the ribosomal site where they are incorporated into proteins

Question 21

anticodon

Answer 21

the 3 nucleotides by which a tRNA recognized an mRNA codon

Question 22

introns

Answer 22

a region in a eukaryotic gene that does not code for a protein of mRNA

Question 23

exons

Answer 23

a region of eukaryotic chromosome that encodes a protein

Question 24

gene expression

Answer 24

genetic information is used within a cell to produce the proteins needed for the cell to function

Question 25

gene repression

Answer 25

blocks the attachment of RNA polymerase to the promoter, thus preventing transcription of the genes into messenger RNA. An RNA-binding repressor binds to the mRNA and prevents translation of the mRNA into protein

Question 26

gene induction

Answer 26

an increase in gene expression due to the presence of an inducer.

Question 27

operon

Answer 27

the operator and promoter sites and structural genes they control

Question 28

inducer

Answer 28

a chemical or environmental stimulus that causes transcription of specific genes

Question 29

positive regulation

Answer 29

a transcription factor is required to bind at the promoter in order to enable RNA polymerase to initiate transcription.

Question 30

mutation

Answer 30

any change in the nitrogenous base sequence of DNA

Question 31

positive selection

Answer 31

a procedure for picking out mutant cells by growing them

Question 32

negative selection

Answer 32

the process of identifying mutations by selecting cells that do not grow using replica plating