Chpt 5

Front 1

nucleic acid

Back 1

macromolecule that stores information

Front 2

nucleotides

Back 2

individual units that consist of three components: a molecule of sugar, a phosphate group, and a base

Front 3

genome

Back 3

an organisms complete set of DNA

Front 4

chromosome

Back 4

one or more unique pieces of DNA that together make up the organisms genome

Front 5

gene

Back 5

a specific sequence of DNA that contains the necessary to produce all or part of a protein molecule

Front 6

alleles

Back 6

different versions of a gene that code for the same trait

Front 7

trait

Back 7

any single characteristic or feature of an organism

Front 8

intron

Back 8

non-coding regions that occur within the gene

Front 9

genotype

Back 9

the genes that an organism carries for a particular trait

Front 10

phenotype

Back 10

the physical manifestation of the instruction

Front 11

transcription

Back 11

the genes sequence is copied from DNA to a middleman molecule called mRNA

Front 12

translation

Back 12

the genes sequence is now encoded in mRNA, which directs the production of a protein

Front 13

recognize and bind (transcription)

Back 13

once RNA polymerase recognizes a promoter site, it binds to one strand of the DNA and begins reading the genes message

Front 14

promoter site

Back 14

a part of the DNA molecule that indicates the start of the gene

Front 15

transcribe (transcription)

Back 15

as the DNA strand is processed through the RNA polymerase, the RNA polymerase builds a single-stranded RNA copy of the gene, called the mRNA transcript

Front 16

terminate (transcription )

Back 16

when the RNA polymerase encounters a code signaling the end of the gene, it stops transcription and releases the mRNA transcript

Front 17

cap and process (transcription )

Back 17

in eukaryotes, mRNAs receive extra processing before they can be translated into a protein. A cap and tail are often added for protection and to promote recognition, and non-coding sections are removed

Front 18

ribosomal subunits

Back 18

the protein-production factories where amino acids are linked together in the proper order to produce the protein

Front 19

transfer RNA (tRNA)

Back 19

interpret the mRNA code, translating the language of DNA into the language of proteins, coded in the linear sequences of amino acids

Front 20

codon

Back 20

three-base sequence in mRNA

Front 21

recognize and initiate protein building (translation )

Back 21

the "start sequence" of the mRNA transcript is recognized by a corresponding tRNA molecule and the two ribosomal subunits. The attachment site of the tRNA molecule binds to the mRNA as the ribosomal subunits assemble around them

Front 22

elongate (translation )

Back 22

as the ribosome moves along the strand of mRNA, each new amino-acid-carrying tRNA molecule binds to the next three bases on the mRNA transcript. After the ribosome attaches the growing protein chain to the new amino acid, the tRNA molecule detaches from the mRNA and floats away

Front 23

terminate (translation )

Back 23

once the ribosome encounters the three-base "stop-sequence", protein assembly is complete. Translation ends and both the protein and the mRNA molecule are released from the ribosome

Front 24

protein synthesis

Back 24

the process of progressively linking together the amino acids specified by the mRNA strand

Front 25

gene expression

Back 25

the production of the protein that the gene's sequence codes for

Front 26

gene regulation

Back 26

whether the gene is turned on or off

Front 27

operon

Back 27

a group of several genes and the elements that control their expression as a unit, all within one unit of a cell's DNA

Front 28

mutation

Back 28

an alteration in the sequence of bases in an organism's DNA

Front 29

point mutations

Back 29

when one base pair is substituted for another, or when a base pair is inserted or deleted

Front 30

chromosomal aberrations

Back 30

changes to the overall organization of the genes on a chromosome

Front 31

biotechnology

Back 31

in which organisms, cells, and their molecules are modified to acheive practical benefits

Front 32

genetic engineering

Back 32

the manipulation of organisms' genetic material by adding, deleting, or transplanting genes fromone organism to another

Front 33

restriction enzymes

Back 33

when they encounter DNA, they cut into small pieces

Front 34

polymerase chsin reaction (PCR)

Back 34

a laboratory technique that allows a tiny piece of DNA to be duplicated repeatedly

Front 35

DNA probe

Back 35

this DNA contains part of the sequence of the gene of interest and has also been modified so that it is radioactive

Front 36

genetic engineering

Back 36

the manipulation of a species' genome in ways that do not normally occur in nature

Front 37

recombinant DNA technology

Back 37

the combination of DNA from two or more sources into a product

Front 38

gene therapies

Back 38

designed to treat or cure a variety of diseases by inserting a functional gene into an individual's cells to replace a defective version of the gene

Front 39

stem cells

Back 39

cells that have the ability to develop into any type of cell in the body

Front 40

short tandem repeats (STRs)

Back 40

characterized by having a short sequence that repeats over and over a dozen or more times

Front 41

inducible

Back 41

normally off, turned on by stimulus

Front 42

repressible

Back 42

normally on, turned off by stimulus