Genes Flashcards
Beadle and Tatum (1941) studied _______ mold. They used _______ to damage DNA. They looked for _______ mutations
bread, X-rays, nutritional
In Arginine, each step is catalyzed by an _______. Beadle and Tatum isolated strains that couldn’t grow unless fed arginine
enzyme
Beadle and Tatum’s findings led to the one-_______/one-_______ hypothesis.
gene, enzyme
The central _______ describes information flow. Information only flows from _______ -> _______ -> _______.
dogma, DNA, RNA, Protein
_______ is the flow from DNA to RNA (which are both _______ _______)
Transcription, nucleic acids
_______ is the flow from RNA to Protein (from _______ _______ to protein)
Translation, nucleic acid
_______ violate the order of information flow using reverse transcriptase to convert _______ into _______
Retroviruses, RNA, DNA
Transcription is DNA-directed _______ of RNA.
synthesis
Only one strand of DNA is copied as RNA, called the _______ strand. The strand of DNA not used as a template is called the _______ strand.
template, coding
In RNA, T (thymine) is replaced by _______
U (uracil)
_______ is used to direct the synthesis of polypeptides
mRNA
_______ is the RNA which is the intermediate form of information from nucleus to cytoplasm for processing
mRNA
_______ is the class of RNA found in ribosomes, and is essential for their function in protein production
rRNA
_______ is the intermediary adapter molecule between mRNA and amino acids during protein synthesis
tRNA
_______ is the RNA which is part of machinery involved in the processing of “pre-mRNA” in splicing
snRNA
_______ _______ is the mediator for proteins synthesized on the rough endoplasmic reticulum
SRP RNA
_______ and _______ are RNA’s involved in the control of gene expression
miRNA, siRNA
_______ and _______ determined how the order of nucleotides in DNA encoded amino acid order
Crick, Brenner
A _______ is a block of three DNA nucleotides corresponding to an amino acid
codon
A _______ mutation is a single nucleotide (nt) insertion/deletion
frameshift
When Crick and Brenner introduced frameshift mutations, the addition or deletion of __ or __ nts shifted the genetic message, but the addition/deletion of __ nts resulted in a normal protein aside from the addition/deletion
1, 2, 3
Crick and Brenner determined that the _______ _______ is read in increments of 3 nts, read continuously.
genetic code
The three stop codons which are used to terminate translation are _______, _______, and _______.
UAA, UGA, UAG
The start codon used to signify the start of translation is _______
AUG
Code is _______, meaning that some amino acids are specified by more than one codon
degenerate
Prokaryotes have a single RNA _______
polymerase
There are two forms of RNA polymerase in prokaryotes: _______ _______ and _______
core polymerase, holoenzyme
The RNA polymerase Holoenzyme is needed to accurately initiate _______, and is formed by the addition of a _______ subunit to the Core Polymerase
synthesis, sigma
Transcription requires a _______ region, which forms recognition and binding site for RNA _______
promoter, polymerase
Transcription requires a _______ site, the site where RNA synthesis begins
start
In transcription, the _______ is the signal to end transcription
terminator
The region from the promotor to the terminator is called the _______ _______
transcription unit
The promoter is found _______ of the start site, and is not _______.
upstream, transcribed
During elongation, RNA Polymerases read the _______ strand in the ___ to ___ direction, and then synthesizes RNA in the ___ to ___ direction as _______ are added
template, 3’, 5’, 5’, 3’, ribonucleotides
During elongation, RNA Polymerase DOES IT ALL! It opens up _______, _______ single strands (like SSB proteins), _______ DNA (like helicase) and then synthesizes RNA.
DNA, stabilizes, unwinds
After the _______ bubble passes during elongation, the now-transcribed DNA is _______ as it leaves the bubble
transcription, rewound
Termination occurs at specific sites. The _______-_______ hybrid within the transcription bubble dissociates. Then _______ _______ releases the DNA, and the DNA _______
RNA-DNA, RNA polymerase, rewinds
The simplest terminator of transcription is a series of ___-___ base-pairs followed by a series of ___-___ base-pairs. This can form a _______, which causes RNA polymerase to pause at _______.
G-C, A-T, hairpin, uracil
___-___ bonds are the weakest bonds, resulting in dissociation of _______ from _______ in the transcription bubble
U-A, RNA, DNA
Prokaryotic transcription is _______ to translation, meaning that mRNA begins to be translated before transcription is finished
coupled
Eukaryotes have 3 RNA polymerases: RNA Pol I transcribes _______, RNA pol II transcribes _______ and some _______, and RNA pol III transcribes _______ and some other _______ RNA’s.
rRNA, mRNA, snRNA, tRNA, small
Each of the three Eukaryotic RNA polymerases recognizes its own _______
promoter
RNA pol I promoters are _______ specific
species
RNA pol II promoters consist of a _______ promoter that can be composed of a number of elements, including the _______ box (which is _______ of the start site)
core, TATA, upstream
RNA pol III promoters are found within the _______ itself
gene
Initiation of transcription at RNA Pol II promoters requires a series of _______ factors. These are necessary to get the RNA pol II enzyme to a _______ and to initiate gene _______. They interact with RNA pol to form the _______ complex at the promoter
transcription, promoter, expression, intiation
In the Eukaryotic initiation complex, a transcription factor recognizes and binds to the _______ _______ sequence, which is part of the _______ promoter. Other transcription factors are recruited, and the initiation _______ begins to build. Ultimately, RNA Pol II associates with the transcription factors and the DNA, forming the initiation _______, and _______ begins.
TATA box, core, complex, complex, transcription
In eukaryotes, the primary transcript must be _______ to become mature mRNA.
modified
One mRNA modification in Eukaryotes is the addition of a 5’ ___. Essentially, _______ is added to the 5’ end, with GTP modified by the addition of a _______ group, called the _______-__ _______ .
cap, GTP, methyl, methyl-G cap
One mRNA modification in eukaryotes is the addition of a 3’ _______-___ _______. This is created by _______-___ polymerase.
poly-A tail, poly-A
_______ are non-coding sequences in eukaryotic genes
Introns
_______ are sequences that will be translated in Eukaryotic genes
Exons
Eukaryotes deal with introns by cutting and putting back together the primary transcript to produce mature _______, called _______-_______ splicing.
mRNA, pre-mRNA splicing
_______s recognize the intron-exon boundaries and combine with other proteins to form _______s, which are responsible for removing introns via _______.
snRNP, spliceosome, splicing
The number of introns per gene and size of introns and exons _______ greatly.
vary
The _______ is all the RNA’s produced from a genome
Transcriptome
_______ is all the proteins produced from a genome
Proteome
_______ splicing is the process of a single primary transcript being spliced into different _______s by including different sets of _______.
Alternative, mRNA, exons
Alternative splicing greatly increase the number and variety of _______s encoded in the cell nucleus without increasing the size of the _______
proteins, genome
It is estimated that ___% of human genes produce multiple splice products (alternative splicing)
95
_______ are the key macromolecular machine involved in translation, and requires the interaction with _______ and _______ to synthesize proteins.
Ribosomes, mRNA, tRNA
tRNA molecules can interact with _______ and _______ _______, and carry the latter to the ribosome for incorporation into a _______
mRNA, amino acids, polypeptide
_______-_______ _______ add amino acids to the acceptor stem of tRNA
Aminoacyl-tRNA synthetases
The _______ _______ in tRNA contains three nucleotides complementary to mRNA codons
Anticodon loop
Each aminoacyl-tRNA synthetase recognizes only one _______ _______ but several _______
amino acid, tRNAs
_______ tRNA has an amino acid added via a _______ reaction using the energy from ATP. This is an activated intermediate molecule that can undergo _______ bond formation spontaneously. The _______ stem is joined to carboxyl terminus, which means that new peptide bonds are formed between the _______ group and _______ group of linked amino acids.
Charged, charging, peptide, acceptor, amino, carboxyl
Ribosomes do not _______ amino acid attached to tRNA
verify
Ribosomes have two subunits: _______ and _______
large, small
The ribosome has multiple tRNA-binding sites: A (_______) site - binds the tRNA carrying the next _______ _______; P (_______) site - binds the tRNA attached to the growing _______ chain; and E (_______) site - binds the tRNA that carried the _______ amino acid added
Aminoacyl, amino acid, Peptidyl, peptide, Exit, previous
The two primary functions of ribosomes is to _______ the mRNA (primarily the _______ subunit) and to form _______ bonds.
decode, small, peptide
_______ _______ is the enzymatic component of the ribosome, and is part of the large subunit. It forms peptide bonds between _______ _______
Peptidyl transferase, amino acids
The activity of ribosomes is thought to be mostly carried out by _______ vs. the protein component
rRNA
In prokaryotic translation, the initiation complex includes: The charged _______ tRNA , the _______ ribosomal subunit, and an _______ strand
Initiator, small, mRNA
The _______ _______ sequence of mRNA positions the small subunit correctly.
Ribosome binding
Initiator tRNA is bound to ___ site with ___ site empty
P, A
Eukaryotic translation initiation is similar to prokaryotic, except the initiating amino acid is _______, it is more complicated, and lacks an RBS (_______ _______ _______) - the small subunit binds to the _______ _______ of mRNA
methionine, Ribosomal binding site, 5’ cap
Translation elongation adds _______ _______. The 2nd charged tRNA can bind to the empty ___ site.
amino acids, A
Translation elongation requires an _______ factor called EF-Tu to bind to _______ and _______. Then the _______ bond can form. The addition of successive amino acids occurs as a cycle, where the tRNA _______ is matched with the mRNA _______, the peptide bond is _______, and the _______ is translocated
elongation, tRNA, GTP, peptide, anticodon, codon, formed, ribosome
Wobble pairing allows less stringent pairing between the 3’ base of the _______ and the 5’ base of the _______. There are fewer _______ than codons, so this allows the lower number of them to accommodate all codons.
codon, anticodon, tRNAs
Elongation continues until the ribosome encounters a _______ _______, which doesn’t bind to tRNA. They are recognized as release factors which release the _______ from the ribosome
stop codon, polypeptide
In eukaryotes, translation may occur in the _______ or the _______ _______ _______ (RER).
Cytoplasm, Rough endoplasmic reticulum
_______ sequences at the beginning of the polypeptide sequence bind to the _______ _______ _______ (SRP) in the cytoplasm. This sequence and the SRP complex are recognized by _______ receptor proteins. _______ holds the ribosome to these receptor proteins.
Signal, Signal recognition particle, RER , docking
_______ are heritable change in the genetic material.
Mutations
A _______ _______ leads to single-nucleotide variation (SNV) in populations
point mutation
A _______ _______ is the substitution of one base for another. There are two categories: _______ if the mutation is purine-purine or pyrimidine-pyrimidine, or _______ if the mutation is purine-pyrimidine.
base substitution, transition, transversion
A _______ _______ is a type of point mutation where the same amino acid is inserted, so there is no net effect
silent mutation
A _______ _______ is a point mutation that changes the amino acid inserted
missense mutation
A _______ _______ is a point mutation that creates a stop codon
nonsense mutation
The gain or loss of 1-50 base pairs is called an _______
indel (insertion/deletion)
A _______ _______ is a mutation where a base is added or deleted, which has profound consequences
Frameshift mutation
Mutations are the starting point for _______
evolution
Frameshift mutations alter the reading frame _______
downstream
