Retrovirus an rna virus that reproduces by means of a

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Unformatted text preview: cule, which then departs from the gene. Cap- extra molecule added to the beginning of an RNA transcript in the nucleus of a eukaryoDc cell. Tail- extra molecule added at the end of an RNA transcript in the nucleus of eukaryoDc cell. Introns- in eukaryotes, a nonexpressed (noncoding) porDon of a gene that is excised from the RNA transcript. Exons- in eukaryotes, a coding porDon of a gene. RNA splicing- the removal of introns and joining of exons in eukaryoDc RNA, forming an mRNA molecule with a conDnuous coding sequence; occurs before mRNA leaves the nucleus. Transfer RNA- a type of ribonucleic acid that funcDons as an interpreter in translaDon. Each tRNA molecule has a specific anDcodon, picks up a specific amino acid, and conveys the amino acid to the appropriate codon on mRNA. AnDcodon- on a tRNA molecule, a specific sequence of three nucleoDdes that us complementary to a codon triplet on mRNA. rRNA- the type of ribonucleic acid that, together with proteins, makes up ribosomes; the most abundant type of RNA. Start codon- on mRNA, the specific three nucleoDde sequence (AUG) to which an iniDator tRNA molecule binds, starDng translaDon of geneDc informaDon. Stop codon- in mRNA, one of three triplets (UAG, UAA, UGA) that signal gene translaDon to stop. MutaDon- a change in the nucleoDde sequence of DNA; a major source of geneDc diversity. Mutagen- a chemical or physical agent that interacts with DNA and causes a mutaDon. Virus- a microscopic parDcle capable of infecDng cells of living organisms and inserDng its geneDc material. Viruses have a very simple structure and are generally not considered to be alive because they do not display all of the characterisDcs associated with life. Bacteriophages- a virus that infects bacteria; also called a phage. Provirus- Viral DNA that inserts into a host genome. Prions- an infecDous form of protein that may mulDply by converDng related proteins to more prions. Prions cause several different animals, including scrapie in sheep, mad cow disease, and Creutzfeldt- Jakob disease in humans. Retrovirus- an RNA virus that reproduces by means of a DNA molecule. Reverse transcriptase- catalyze reverse transcripDon, the synthesis of DNA on an RNA template. Biology notes from readings Chapter 24 ! 3 cooperaDve lines of defense that protect us...
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This document was uploaded on 03/02/2014 for the course BIO 101 at University of Tennessee.

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