Chapter 17 From Gene to Protein Flashcards

688639757	one gene-one polypeptide hypothesis	The premise that a gene is a segment of DNA that codes for one polypeptide.	0
688639758	transcription	Synthesis of an RNA molecule from a DNA template.	1
688639759	messenger RNA (mRNA)	Carries genetic message from the DNA to he protein-synthesizing machinery of the cell.	2
688639760	translation	The synthesis of a polypeptide, which occurs under the direction of mRNA.	3
688639761	RNA processing	The modification of mRNA before it leaves the nucleus that is unique to eukaryotes.	4
688639762	primary transcript	The initial mRNA transcript that is transcribed from a protein coding gene. Also called pre-mRNA.	5
688639763	triplet code	Three-nucleotide long set that specifies a specific amino acid for a polypeptide chain.	6
688639764	template strand	The DNA strand that provides the template for ordering the sequence of nucleotides in an mRNA transcript.	7
688639765	codons	mRNA base triplets.	8
688639766	reading frame	Reading mRNA nucleotides in the correct groupings.	9
688639768	RNA polymerase	Enzyme that links together the growing chain of ribonucleotides during transcription.	10
688639769	promoter	A specific nucleotide sequence in DNA that binds RNA polymerase and indicates where to start transcribing mRNA.	11
688639770	terminator	In prokaryotes, a special sequence of nucleotides in DNA that marks the end of a gene.	12
688639771	transcription unit	stretch of DNA that's transcribed to RNA	13
688639772	transcription factors	collection of proteins that mediate the binding of RNA polymerase and the initiation of transcription	14
688639773	transcription initiation complex	the assembly of transcription factors and RNA polymerase	15
688639774	TATA box	crucial promoter DNA sequence	16
688639775	5' cap	The 5' end of a pre-mRNA molecule modified by the addition of a cap of guanine nucleotide.	17
688639776	poly-A tail	Modified end of the 3' end of an mRNA molecule consisting of the addition of some 50 to 250 adenine nucleotides.	18
688639777	RNA splicing	Process by which the introns are removed from RNA transcripts and the remaining exons are joined together.	19
688639778	introns	Noncoding segments of nucleic acid that lie between coding sequences.	20
688639779	exons	Coding segments of eukaryotic DNA.	21
688639780	splicosome	Different particles that recognize splice sites are compiled in a large assembly., A complex of RNA and protein subunits. Removes introns from a transcribed pre-RNA segments.	22
688639781	ribozymes	RNA molecules that function as enzymes.	23
688639782	alternative RNA splicing	Genes giving rise to two or more different polypeptides depending upon which segments are treated as exons.	24
688639783	domains	Discrete structural and functional regions of proteins.	25
688639784	transfer RNA (tRNA)	Interpreter of a series of codons along a mRNA molecule.	26
688639785	anticodon	Specialized base triplet at one end of a tRNA molecule that recognizes a particular complementary codon on an mRNA molecule.	27
688639786	wobble	Flexibility in the base-pairing rules in which the nucleotide at the 5' end of a tRNA anticodon can form hydrogen bonds with more than one kind of base in the third position of a codon.	28
688639788	ribosomal RNA (rRNA)	RNA molecules that construct ribosomal subunits.	29
688639789	ribosomal P site	Site that holds tRNA carrying the growing polypeptide chain.	30
688639790	ribosomal A site	Site that holds the tRNA carrying the next amino acid to be added to the chain.	31
688639791	ribosomal E site	Site where discharged tRNAs leave the ribosome.	32
688639792	polyribosomes	Strings of ribosomes that work together to translate a RNA message.	33
688639793	signal peptide	A stretch of amino acids on a polypeptide that targets the protein to a specific destination in a eukaryotic cell.	34
688639794	signal-recognition particle	A protein-RNA complex that recognizes a signal peptide as it emerges from the ribosome.	35
688639795	mutations	Random errors in gene replication that lead to a change in the sequence of nucleotides. The source of all genetic diversity.	36
688639796	point mutations	Changes in a DNA sequence caused by substitution of one nucleotide for another.	37
688639798	missense mutations	Most common type of mutation, a base pair mutation in which the new codon makes sense in that it still codes for an amino acid.	38
688639799	nonsense mutations	A mutation that changes an amino acid codon to one of three stop codons, resulting in a shorter and usually nonfunctional protein.	39
688639801	frameshift mutation	Mutation occurring when the number of nucleotides inserted or deleted is not a multiple of three, resulting in improper grouping of nucleotides into codons.	40
688639802	mutagens	physical and chemical agents that interact with DNA to cause mutations	41