Chapter 10 Flashcards
Adenine (A)
A double ring nitrogenous base found in DNA and RNA
Genetic Code
The set of rules giving the correspondence between codons and amino acids.
phages
a virus that infects bacteria, also called bacteriophage
AIDS
Acquired immunodeficiency syndrome;
Lysogenic Cycle
A bacteriophage reproductive cycle in which the viral genome in incorporated into the bacterial host chromosome as a prophage; and the host cell is not killed or lysed until the viral genome leaves the host chromosome.
Bacteriophages
A virus that infects a bacteria called a phage
Cap
Extra nucleotides added to the beginning of an RNA transcript in the nucleus of a eukaryotic cell
Molecular Biology
The study of molecular basis of heredity; molecular genetics.
Cytosine (C)
A single ring nitrogenous base found in DNA and RNA
DNA
The genetic material that organisms inherit from their parents; a double stranded helical macromolecule consisting of nucleotide monomers with deoxyribose sugar, a phosphate group, and the nitrogenous base adenine, cytosine, guanine, and thymine
DNA Polymerase
The enzyme that assembles DNA nucleotides into polynucleotides using a preexisting strand of DNA as a template.
Double Helix
The twisted ladder shape of DNA
Emerging Viruses
A recently occurred virus, or one that has come to the attention of medical scientists
Exons
In eukaryotes, a coding portion of the gene
Start Codon
On mRNA the specific three nucleotide sequence (AUG) to which an initiator tRNA molecule binds starting translation of genetic information
Stop Codon
In mRNA, one of three triplets (UAG, UAA, UGA) that signal gene translation to stop
Sugar Phosphate Backbone
The alternating chain of sugar and phosphate to which DNA and RNA nitrogenous bases are attached
polynucleotide
a polymer made up of many nucleotides covalently bonded together.
Guanine
A double-ring nitrogenous base found in DNA and RNA.
HIV
Human immunodeficiency virus; the retrovirus that attacks the human immune system and causes AIDS.
Introns
In eukaryotes, a non expressed portion of a gene that is excised from the RNA transcript.
Lysogenic Cycle
A bacteriophage reproductive cycle in which the viral genome in incorporated into the bacterial host chromosome as a prophage; and the host cell is not killed or lysed until the viral genome leaves the host chromosome.
prion
an infectious form of protein that may multiply by converting related proteins to more prions. Prions cause many related diseases in different animals,including scrapie in sheep, mad cow disease, and Creutzfeldt-Jakob disease in humans.
Lytic Cycle
A viral reproductive cycle resulting in the release of new viruses by result of lysis of the host cell.
Messenger RNA
The type of ribonucleic acid that encodes genetic information from DNA and conveys it to ribosomes where the information is translated into amino acid sequences.
Molecular Biology
The study of molecular basis of heredity; molecular genetics.
Mutagen
A chemical or physical agent that interacts with DNA and causes a mutation.
Mutation
A change in the nucleotide sequence of DNA
Nucleotide
AN organic monomer consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group. The building blocks of a nucleic acid.
Tail
Extra nucleotides added to the end of an RNA transcript in the nucleus of a eukaryotic cell.
Terminator
A special sequence of nucleotides in DNA that marks the end of a gene. It signals RNA polymerase to release the newly made RNA molecule, which then departs from the gene.
Thymine
A single-ring nitrogenous base found in DNA.
Transcription
The synthesis of RNA on a DNA template.
promoter
a specific nucleotide sequence in DNA, located at the start of the gene, that is the binding site for RNA polymerase and the place where transcription begins
prophage
Phage DNA that has inserted into the DNA of a prokaryotic chromosome
provirus
Viral DNA that inserts into a host genome
retrovirus
A RNA virus that reproduces by means of a DNA molecule. It reverse-transcribes its RNA into DNA, inserts the DNA into a cellular chromosome, and then transcribes more copies of the RNA from the viral DNA. HIV and a number of cancer-causing viruses are retroviruses.
reverse transcriptase
an enzyme that catalyzes the synthesis of DNA on a RNA template
ribosomal RNA
the type of ribonucleic acid that, together with proteins, makes up ribosomes: the most abundant type of RNA
RNA polymerase
an enzyme that links together the growing chain of RNA nucleotides during transcription, using a DNA strand as a template
RNA splicing
the removal of introns and joining of exons in eukaryotic RNA, forming an mRNA molecule with a continuous coding sequence: occurs before mRNA leaves the nucleus.
Transfer RNA
a type of ribonucleic acid that functions as an interpreter in translation. Each tRNA molecule has a specific anticodon, picks up a specific amino acid, and conveys the amino acid to the appropriate codon on mRNA
Translation
the synthesis of a polypeptide using the genetic information encoded in an mRNA molecule. There is a change of “language” from nucleotides to amino acids.
uracil
a single ring nitrogenous base found in RNA
virus
a microscopic particle capable of infecting cells of living organisms and inserting its genetic material. Viruses have a very simple structure and are generally not considered to be alive because they do not display all of the characteristics associated with life.
