Chapter 10 Flashcards
Acquired immunodeficiency syndrome; the late stages of
HIV infection, characterized by a reduced number of T cells and the appearance of characteristic opportunistic infections.
AIDS
A double-ring nitrogenous base found in DNA and RNA.
Adenine
On a tRNA molecule, a specific sequence of three nucleotides that is complementary to a codon triplet on mRNA.
Anticodon
A virus that infects bacteria; also called a phage.
Bacteriophage
The protein shell that encloses a viral genome. It may be rod-shaped, polyhedral, or more complex in shape.
Capsid
A three-nucleotide sequence in mRNA that specifies a particular amino acid or polypeptide termination signal; the basic unit of the genetic code.
Codon
The union (mating) of two bacterial cells or protist cells and the transfer of DNA between the two cells.
Conjugation
A single-ring nitrogenous base found in DNA and RNA.
Cytosine
An enzyme, essential for DNA replication, that catalyzes the covalent bonding of adjacent DNA strands; used in genetic engineering to paste a specific piece of DNA containing a gene of interest into a bacterial plasmid or other vector.
DNA Ligase
An enzyme that assembles DNA nucleotides into polynucleotides using a preexisting strand of DNA as a template.
DNA polymerase
The form of native DNA, referring to its two adjacent polynucleotide strands wound into a spiral shape.
Double Helix
A virus that has appeared suddenly or has recently come to the attention of medical scientists.
Emerging Virus
A piece of DNA that can exist as a bacterial plasmid. The F factor carries genes for making sex pili and other structures needed for conjugation, as well as a site where DNA replication can start. F stands for fertility.
F-Factor
The set of rules that dictates the correspondence between RNA codons in an mRNA molecule and amino acids in protein.
Genetic Code
A double-ring nitrogenous base found in DNA and RNA.
Guanine
Human immunodeficiency virus, the retrovirus that attacks the
human immune system and causes AIDS.
HIV
A type of bacteriophage replication cycle in which the viral genome is incorporated into the bacterial host chromosome as a prophage. New phages are not produced, and the host cell is not killed or lysed unless the viral genome leaves the host chromosome.
Lysogenic Cycle
A type of viral replication cycle resulting in the release of new viruses by lysis (breaking open) of the host cell.
Lytic Cycle
The study of the molecular basis of genes and gene expression; molecular genetics.
Molecular Biology
A chemical or physical agent that interacts with DNA and causes a mutation.
Mutagen
The creation of a mutation.
Mutagenesis
A change in the nucleotide sequence of an organism’s DNA; mutation also can occur in the DNA or RNA of a virus; the ultimate source of genetic diversity.
Mutation
An organic monomer consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group. Nucleotides are the building blocks of nucleic acids.
Nucleotide
One of two of a ribosome’s binding sites for tRNA during translation. The P site holds the tRNA carrying the growing polypeptide chain. (P stands for peptidyl tRNA.)
P-Site
A small ring of independently replicating DNA separate from the main chromosome(s). Plasmids are found in prokaryotes and yeast.
Plasmid
