Chapter 19- Eukaryotic Genomes Flashcards

338702741	activator	A transcription factor that binds to an enhancer and stimulates transcription of a gene
338702742	alternative RNA splicing	A type of regulation at the RNA-processing level in which different mRNA molecules are produced from the same primary transcript depending on which RNA segments are treated as exons and which as introns.
338702743	cell differentiation	The structural and functional divergence of cells as they become specialized during a multicellular organism's development; dependent on the control of gene expression.
338702744	chromatin	The complex of DNA and proteins that makes up a eukaryotic chromosome. When the cell is not dividing, chromatin exists as a mass of very long, thin fibers that are not visible with a light microscope.
338702745	control element	A segment of noncoding DNA that helps regulate transcription of a gene by binding proteins called transcription factors.
338702746	differential gene expression	The expression of different sets of genes by cells with the same genome.
338702747	enhancer	A DNA segment containing multiple control elements that may be located far away from the gene it regulates.
338702748	epigenetic inheritance	Inheritance of traits transmitted by mechanisms not directly involving the nucleotide sequence.
338702749	euchromatin	The more open, unraveled form of eukaryotic chromatin that is available for transcription.
338702750	genomic imprinting	Phenomenon in which expression of an allele in offspring depends on whether the allele is inherited from the male or female parent.
338702751	heterochromatin	Nontranscribed eukaryotic chromatin that is so highly compacted that it is visible with a light microscope during interphase.
338702752	histone	A small protein with a high proportion of positively charged amino acids that binds to the negatively charged DNA and plays a key role in its chromatin structure.
338702753	histone acetylation	the attachment of acetyl groups to certain amino acids of histone proteins
338702754	microRNA (miRNA)	small single-stranded RNa molecules that can bind to complementary sequences in mRNA molecules to block expression of specific mRNA molecules
338702755	multigene family	A collection of genes with similar or identical sequences, presumably of common origin.
338702756	nucleosome	The basic, beadlike unit of DNA packaging in eukaryotes, consisting of a segment of DNA wound around a protein core composed of two copies of each of four types of histone.
338702757	oncogene	A gene found in viruses or as part of the normal genome that is involved in triggering cancerous characteristics
338702758	p53 gene	The "guardian angel of the genome," p53 is expressed when a cell's DNA is damaged. Its product, p53 protein, functions as a transcription factor for several genes.
338702759	proteasome	A giant protein complex that recognizes and destroys proteins tagged for elimination by the small protein ubiquitin.
338702760	proto-oncogene	a gene that regulates normal cell division but that can become a cancer-causing oncogene as a result of mutation or recombination
338702761	pseudogene	A DNA segment very similar to a real gene but which does not yield a functional product; a gene that has become inactivated in a particular species because of mutation.
338702762	ras gene	This gene codes for Ras protein, a G protein that relays a growth signal from a growth-factor receptor on the plasma membrane to a cascade of protein kinases that ultimately results in the stimulation of the cell cycle. Many ras oncogenes have a point mutation that leads to a hyperactive version of the Ras protein that can lead to excessive cell division.
338702763	repetitive DNA	Nucleotide sequences, usually noncoding, that are present in many copies in a eukaryotic genome. The repeated units may be short and arranged tandemly (in series) or long and dispersed in the genome.
338702764	repressor	A protein that suppresses the transcription of a gene.
338702765	retrotransposon	A transposable element that moves within a genome by means of an RNA intermediate, a transcript of the retrotransposon DNA.
338702766	RNA interference RNA (RNAi)	A technique to silence the expression of selected genes in nonmammalian organisms. The method uses synthetic double-stranded RNA molecules matching the sequence of a particular gene to trigger the breakdown of the gene's messenger RNA.
338702767	small interfering RNA (siRNA)	RNAs of similar size and function as miRNAs, responsible for RNA interference
338702768	transcription factor	A regulatory protein that binds to DNA and stimulates transcription of specific genes.
338702769	transposon	A transposable genetic element that moves within a genome by means of a DNA intermediate.
338702770	tumor-suppressor gene	a gene whose protein products inhibit cell division, thereby preventing uncontrolled cell growth (cancer)