Ap Biology Chapter 18 Flashcards

6152390327	Operator	The regulatory "switch" that is a segment of DNA usually positioned within the promoter	0
6152408601	Operon	The entire stretch of DNA that includes the operator, the promoter, and the genes that they control	1
6152419883	Repressor	The way operons can be switched off	2
6152431360	Regulatory gene	The gene that produces the repressor	3
6152516452	Corepressor	A molecule that cooperates with a repressor protein to switch an operon off	4
6152525349	Repressible operon	An operon that is usually on; binding of a repressor to the operator shuts off transcription	5
6152533016	Inducible operon	An operon that is usually off; a molecule called an inducer inactivates the repressor and turns on transcription	6
6152540501	Lac operon	An inducible operon that also contains genes that code for enzymes used in the hydrolysis and metabolism of lactose	7
6152566561	Inducer	A molecule that inactivates the repressor to turn the lac operon on	8
6152595195	Negative feedback loops	The type of feedback loop that trp and lac operons have	9
6152603468	Catabolite activator protein (CAP)	An activator that binds with cyclic AMP when there is a scarcity of glucose	10
6152610694	Differential gene expression	The expression of different genes by cells with the same genome	11
6152614131	Histone accetylation	When acetyl groups are attached to positively charged lysines in histone tails causing it to unravel	12
6152655647	Histone methylation	When methyl groups attach to histones causing the chromatin to condense	13
6152674857	Genomic imprinting	When methylation regulates expression of either the maternal or paternal alleles of certain genes at the start of development	14
6152686490	Epigenetic inheritance	The inheritance of traits transmitted by the mechanisms not directly involving the nucleotide sequence	15
6152747833	Control elements	Segments of noncoding DNA that help regulate transcription by binding certain proteins	16
6152807223	Alternative gene splicing	Different mRNA molecules are produced from the same primary transcript, depending on which RNA segments are treated as exons and which as introns	17
6152819275	Proteasomes	Giant protein complexes that bind protein molecules and degrade them	18
6152828003	MicroRNAs (miRNAs)	Small single-stranded RNA molecules that can bind to mRNA	19
6153059506	RNA interference (RNAi)	The phenomenon of inhibition of gene expression by RNA molecules	20
6153070029	Small interfering RNAs (siRNAs)	The molecule that causes RNAi	21
6153104375	Cell differentiation	The process by which cells become specialized in structure and function	22
6153117157	Cytoplasmic determinants	Maternal substances in the egg that influence early development	23
6153136643	Morphogenesis	The physical processes that give an organism its shape	24
6153236420	Determination	Committing a cell to its final fate	25
6153242916	Pattern formation	The development of a spatial organization of tissues and organs	26
6153279589	Embryonic lethals	Embryos with lethal mutations	27
6153298898	Maternal effect genes	Genes that encode for cytoplasmic determinants that initially establish the axes of the body of Drosophila	28
6153309471	Bicoid	A maternal gene that affects the front half of the body	29
6153315656	Oncogenes	Cancer-causing genes	30
6153333358	Proto-oncogenes	The corresponding normal cellular genes that are responsible for normal cell growth and division	31
6153343167	Tumor-suppressor genes	Genes that help prevent uncontrolled cell growth	32
6153348514	Ras gene	A gene that when it mutates, can cause a hyperactive Ras protein and increase cell division	33
6153361238	P53	Mutations of this gene will prevent suppression of the cell cycle	34