Chapter 15: Genes and How They Work Flashcards

3128979572	How many chromosomes do humans have?	-46 total -23 pairs -get 23 from mom and 23 from dad	0
3128981795	What determines your traits?	DNA in the nucleus of cells	1
3128982747	What determines protein sequence?	DNA sequence	2
3128984119	How man genes in the human genome?	About 20,000	3
3128984651	DNA holds info for _______	proteins produced	4
3128985419	What does the central dogma state?	DNA is transcribed to make RNA which is translated to make protein	5
3131521335	How are genes expressed?	Genes are transcribed into RNA sequence, RNA is translated into protein	6
3131535475	What did Francis Crick and Sydney Brenner do?	-They determined how the order of nucleotides in DNA encoded amino acid order	7
3131541125	___________ bases code for _________ amino acid	Three bases code for one amino acid	8
3131545919	Codon	3 nucleotides that codon for an amino acid	9
3131550476	Who discovered that a nucleotide sequence is read 3 bases at a time?	Francis Crick and Sydney Brenner	10
3131555594	Who identified the codons that specify each amino acid?	Marshall Nirenberg	11
3131560814	Genetic code is ____________	degenerate	12
3131561504	Degenerate	some amino acids are specified by more than one codon	13
3131563450	Genetic code is practically ______________	universal	14
3131568586	What is the strongest evidence that all living things share common ancestry?	The universality of the genetic code	15
3131573402	What is a chromosome?	tightly wound structure of DNA and protein	16
3131575119	What percentage of the human genome codes for proteins?	5%	17
3131576876	What is a chromatin?	DNA wrapped around protein	18
3131577637	Tightly wound _________ makes a __________	chromatin; chromosome	19
3131579950	What is a gene?	sections of DNA that hold information for building a protein (amino acid sequence)	20
3131583953	What is a promoter?	sign post that says "START HERE!	21
3131588070	What must be removed from a gene before protein synthesis?	introns	22
3131588985	What must be spliced together before protein synthesis?	exons	23
3131591879	Central dogma	DNA is transcribed into RNA which is translated into protein	24
3131594016	What is RNA polymerase?	enzyme that transcribes gene	25
3131596254	What three things are required for prokaryotic transcription?	-promoter -start site -termination site	26
3131597556	What is a transcription unit?	-promoter -start site -termination site	27
3131598808	What is a termination site?	a signal to end transcription	28
3131603926	What is the site where unzipping/unwinding of DNA begins?	TATA box	29
3131606401	Transcription heads _____ until it hits the __________	downstream; termination site	30
3131607460	upstream	-1, -2, -3, etc...	31
3131608449	downstream	+1, +2 +3, etc...	32
3131614313	What does the promoter do?	Forms a recognition and binding site for the RNA polymerase	33
3131615001	Where is the promoter found?	upstream of the start site (to the left, negative numbers)	34
3131616634	Is the promoter transcribed?	no	35
3131621680	initiation		36
3131621681	elongation		37
3131624356	termination	-sequence that signals "stop" to polymerase -RNA polymerase released the DNA -DNA rewinds	38
3133398158	What comes in physical contact with the promoter during initiation to stabilize the enzyme?	sigma (a polypeptide)	39
3133398547	What does sigma do during initiation?	Sits down (physical contact with) -10 and -35, and physically unwinds the double helix then falls off	40
3133402216	What happens once sigma leaves?	the rest of the enzyme (core enzyme) catalyzes transcription	41
3133405478	What is the production of the RNA molecule called?	transcription	42
3133420172	What happens during elongation?	DNA unwinds downstream and rewinds upstream	43
3133423388	What is the region containing the RNA polymerase , DNA template, and growing DNA strand	transcription bubble	44
3133427078	In what phase is the RNA molecule made based on the DNA template?	Elongation	45
3133428427	The transcription bubble moves ______ the enzyme	with	46
3133429349	The transcription bubble will move down the entire gene until it hits the ______________	termination sequence	47
3133431722	What is the first nucleotide added called?	+1	48
3133432704	What happens during termination	-a sequence signals stop to polymerase -RNA polymerase releases the DNA -DNA rewinds	49
3133444683	What causes RNA polymerase to pause	mRNA hairpin	50
3133450113	mRNA hairpin	-very stable structure because of lots of hydrogen bonds -causes structure to stall at weak base pair which wobbles and falls apart	51
3133453052	What is another name for gene expression?	Protein production	52
3133457794	How many RNA polymerases are in eukaryotic transcription?	Three: -RNA polymerase I -RNA polymerase II -RNA polymerase III	53
3133460057	Each RNA polymerase recognizes its own ____________	promoter	54
3133461612	Why does each RNA polymerase recognize its own promoter?	it needs to know where to land	55
3133487726	What must happen to the primary transcript before it can become mature mRNA?	it must be modified	56
3133491153	Which modifications must take place?	-addition of a 5' cap -addition of a 3' poly-A tail -removal of non-coding sequences	57
3133492154	What are non-coding sequences?	introns	58
3133493239	UTR	-untranslated region -regulatory sequences	59
3133495687	What is the purpose of the 5' cap and 3' poly-A tail?	protection	60
3133496505	When are the 5' cap and 3'poly-A tail added?	After the transcript is made, before it leaves the nucleus	61
3133501331	Before translation ________ must be removed and ________ must be spliced together	introns; exons	62
3133504570	What must happen before translation (into a protein)	-5' cap added -3' poly-A tail added -introns removed	63
3133505729	Spiceosome	-removes introns -splices exons together	64
3133506970	What is the spliceosome made of?	RNA and proteins	65
3133512711	What is alternative splicing?	When a single primary transcript can be spliced into different mRNAs by the inclusion of different sets of exons	66
3133514948	What gives the organism opportunity to make different proteins from a single gene?	Alternative splicing	67
3133517397	Each gene can code for _______ protein(s)	many different	68
3133519571	_______ molecules carry amino acids to the ribosome for incorporation into a polypeptide	tRNA (transfer RNA)	69
3133522445	What is the "interpreter" that interprets a nucleotide sequence into an amino acid sequence (from nucleotides to proteins)?	tRNA	70
3133523498	The anti-codon is ________ with the codon	complementary	71
3133524855	Acceptor end	accepts amino acids	72
3133526987	Anticodon	binds to the codons within RNA and brings with it a particular amino acid	73
3133529760	What is the enzyme that adds the amino acid?	tRNA	74
3133530955	For every codon there is _____________	an anti codon	75
3133534190	If there are 64 codons there must be _____ tRNA molecules with specific amino acids	64	76
3133540328	Each aminoacyl-tRNA synthetase recognizes ______amino acid(s) and _______ tRNAs	only one amino acid but several tRNAs	77
3133541625	What does aminoacyl-tRNA synthetase do?	It is an enzyme that grabs tRNA and adds appropriate amino acids	78
3133613140	tRNA charging reaction		79
3133615628	In the tRNA charging reaction, the _______ specifies which ________ will be placed	anticodon; amino acid	80
3133617728	In the tRNA charging reaction, what specifies which amino acid will be placed?	anticodon	81
3133625274	What are the two important sites on the aminoacyl-tRNA synthetase?	-amino acid site (at the top) -tRNA site (on the side)	82
3133632155	The ribosome has ________ tRNA binding site(s)	multiple	83
3133633467	What are the binding sites on the ribosome for tRNA?	-P site -A site -E site	84
3133634660	P site	binds the tRNA attached to the growing peptide chain	85
3133636379	A site	binds the tRNA carrying the next amino acid	86
3133638204	E site	-binds the tRNA that carried the last amino acid -EXIT site for tRNA that has given up its amino acid	87
3133641458	What is a ribosome made of?	rRNA and protein	88
3133642193	What is the workbench for translation?	the ribosome	89
3133644301	Where is mRNA translated into protein?	the ribosome	90
3133646060	What is the bond between amino acids?	peptide bond	91
3133647916	What is the structure of a ribosome?	-large subunit -small subunit -mRNA strand in between	92
3133671715	What happens during initiation of translation?	-mRNA comes in contact with small subunit -first tRNA carrying amino acid	93
3133679808	What happens during termination of translation?	a release factor releases the polypeptide chain, jams everything up, making everything fall apart	94
3133685394	What does the stop codon code for?	nothing	95
3133691736	What is protein targeting?	-First 3 amino acids is a signal to drag translating machine to the RER -SRP binds to peptide, it is dragged and docked at RER -finished polypeptide is inside RER, and goes via vesicle to the golgi apparatus	96
3133707283	What happens to the polypeptide when it is finished?	It is inside the RER, and goes via vesicle to the golgi apparatus	97
3133708201	Where does protein targeting happen?	in the cytoplasm	98
3133709098	What is an SRP	signal recognition particle, bind to signal polypeptide	99
3133713573	What do genes determine?	What proteins are produced	100
3133716582	What is a point mutation?	When one nucleotide is changed (change of one base to another)	101
3133717888	What are the types of point mutations?	-silent -missense -nonsense	102
3133719620	Silent mutation	-doesn't matter, still has the codon for the same protein	103
3133722934	Missense mutation	-when a base is changed so that codon codes for a different amino acid -protein has been changed -may or may not matter	104
3133736452	Nonsense mutation	-no sense can be made of the codon because it is now a stop codon -protein cannot be produced -typically very detrimental	105
3133743000	Example of missense mutation	sickle cell anemia	106
3133750699	Frameshift mutation	-addition or deletion of a single base (nucleotide) -more profound consequences -alters reading frame downstream	107
3133755195	If a frameshift mutation deletes or adds 3 nucleotides, will there be a shift in the reading frame?	no	108
3133758257	What are the two big structural changes in chromosomes?	deletion, duplication, inversion, translocation	109
3133759356	Deletion (in chromosomes)	loss of a portion of a chromosome	110
3133759977	Duplication (in chromosomes)	a region of a chromosome is duplicated	111
3133767794	Too much of a protein (duplication) can cause ___________	cancer	112
3133800741	Inversion	genes change position	113
3134581961	When in inversion detrimental?	When it happens within a gene	114
3134603232	Reciprocal translocation	-pieces of a chromosome break off and attach to another chromosome -all the same genes are present, just located on a different chromosome	115
3134619222	What is the starting point for evolution?	mutations	116
3134624890	There must be a _________ between the amount of new variation and health of the species.	balance	117