DNA...Chapters 13 & 14!!

1.adenine:A purine; a nitrogen-containing base in certain nucleotides. Base pairs with thymine in DNA.
2.cytosine:Pyrimidine; one of the nitrogen-containing bases in nucleotides.
3.guanine:Nitrogen-containing base in one of four nucleotide monomers of DNA or RNA.
4.thymine:A nitrogen-containing base; one of the nucleotides in DNA.




5.bacteriophage:Category of viruses that infect bacterial cells.
6.cloning:Making a genetically identical copy of DNA or of an organism.
7.deoxyribonucleic acid:Of cells and many viruses, the molecule of inheritance. H bonds join its two helically twisted nucleotide strands, one of which has instructions for synthesizing all of the enzymes and other proteins required to build and maintain cells.

8.DNA ligase:Enzyme that seals new base-pairings during DNA replication.
9.DNA polymerase:Enzyme of replication and repair that assembles a new strand of DNA on a parent DNA template.
10.DNA repair:Enzyme-mediated process that fixes small-scale alterations in a DNA strand by restoring the original base sequence.
11.DNA replication:Any process by which a cell duplicates its DNA molecules before dividing.
12.nucleotide:Small organic compound with deoxyribose, a nitrogenous base, and a phosphate group. Monomer for adenosine phosphates, nucleotide coenzymes, and nucleic acids.
13.x-ray diffraction image:Pattern that forms on film exposed to x-rays that have been directed at a molecule; reveals positions of atoms, not the molecular structure.
14.anticodon:Series of three nucleotide bases in tRNA; can base-pair with an mRNA codon.
15.base sequence:Sequential order of bases in a DNA or RNA strand.
16.base-pair substitution:One amino acid has replaced another during protein synthesis.
17.carcinogen:Any substance or agent that can trigger cancer.
18.codon:One of 64 possible base triplets in an mRNA strand. A code word for an amino acid in a polypeptide chain; a few codons also act as START or STOP signals for translation.
19.deletion:At cytological level, loss of a segment from a chromosome. At molecular level, loss of one to a few base pairs from a DNA molecule.
20.exon:One of the base sequences of an mRNA transcript that will become translated.
21.gene mutation: A small-scale change in the nucleotide sequence of a DNA molecule.
22.genetic code:The correspondence between nucleotide triplets in DNA and specific sequences of amino acids in a polypeptide chain; the basic language of protein synthesis in cells.
23.insertion:Insertion of one to a few bases into a DNA strand. Also, a movable attachment of muscle to bone.
24.intron:A noncoding portion of a pre-mRNA transcript; excised before translation.
25.ionizing radiation:High-energy wavelengths.
26.RNA:A single strand of ribonucleotides transcribed from DNA, then translated into a polypeptide chain. The only RNA encoding protein-building instructions.
27.mutation rate:Of a gene locus, the probability that a spontaneous mutation will occur during or between DNA replication cycles