Chapter 15 Flashcards
How DNA makes a functional protein. This is a portion of DNA that will be made into a protein.
Piece or segment of DNA that makes proteins or different amounts of proteins. A unit of heredity, a segment of DNA that encodes RNA and/or a protein.
Genes
How we take a gene and make a protein from it.
Gene Expression
Gene Expression in Prokaryotes:
DNA –(transcription- make RNA)–> mRNA–(translation-make protein)–> Protein
Gene Expression in Eukaryotes:
DNA–(transcription)–> pre mRNA–(RNA processing-take DNA to make mRNA)–> mature mRNA–(translation)–> Protein
Make an RNA copy of DNA. The process of making mRNA from DNA.
Transcription
Where transcription begins on DNA. The signal on the strand of DNA that begins transcription. Site of RNA polymerase binding.
Promoter
Where transcription ends. The signal on strand of DNA that ends transcription.
Terminator
mRNA cannot be made until what is activated?
The promoter
Site for the binding of regulatory proteins. The role of the regulatory proteins is to influence the rate of transcription. These can be found in a variety of locations.
Regulatory sequences
Contains the information that specifies an amino acid sequence.
Transcribed region
Steps of Transcription:
1.) Initiation
2.) Elongation-RNA polymerase
3.) Termination
This term describes the strand of DNA that the mRNA copy will be made from. Only 1 strand of DNA is used to make RNA which is known as this. RNA synthesized from this, a non-coding strand. Strand varies between genes
template or template strand
Direction of transcription. Direction RNA synthesized is….
5’ to 3’
makes RNA, that’s transcription. This enzyme makes RNA.
RNA polymerase
Reads DNA and uses it to make RNA.
Elongation RNA polymerase.
DNA double helix is not a template strand, it is the what? Goes in what direction?
The coding strand DNA. 5’ to 3’
The template DNA or complementary DNA sequence goes in what direction?
3’ to 5’
Order of Transcription and Translation:
1.) coding strand: starting point–5’ to 3’
2.) template strand: opposite of starting point– 3’ to 5’
3.) Start Transcription:
- mRNA: use AUGC – 5’ to 3’
4.) Start Translation:
- tRNA: AUCG opposing from previous one (anti-codons)
- polypeptide: translate tRNA (amino acids)
In eukaryotes, this is the process of making a mature mRNA from pre-mRNA. Pre-mRNA to mature mRNA.
RNA processing
RNA processing in Eukaryotes include:
1.) Splicing
-exons, introns
2.) 5’ cap and 3’ poly A tail
Cut some sequencing out and leave some mRNA in. The process of removing introns from RNA and linking together exons.
Splicing
Stay expressed
exons
removed
introns
Allow mRNA to be recognized and exit nucleus.
5’ cap
Stabilize mRNA. This addition during RNA processing stabilizes mRNA.
3’ poly A tail
This molecule carries DNA’s message out of the nucleus.
mRNA
When mRNA is translated into a polypeptide. Take mRNA to make a protein. The process of making proteins from mRNA.
Translation
3 mRNA nucleotides which specify an amino acid. Sequence of 3 mRNA’s that are read together.
codon
START making protein. AUG (methionine)
start codon
STOP making protein. Include UAA, UAG, UGA.
Stop/Termination/Nonsense Codons
Needs it to make amino acids
Codon table
More than one codon can specify the same amino acid.
Degenerate
Last part of translation involves this. This part of translation allows binding of this to mRNA codon. Transfer RNA. DNA sequence of gene transcribed into mRNA.
tRNA
3 RNA nucleotide part of tRNA molecule. The set of 3 tRNA’s that are read together and are complimentary to mRNA.
anticodon
What brings amino acid to ribosome? This form of RNA has an amino acid attached.
tRNA
Cloverleaf pattern. Recognizes mRNA codon and has amino acid attached.
tRNA
charging tRNA, adding amino acid to acceptor stem. Adding amino acid to tRNA “charging.”
Aminoacylation
Where does translation take place?
Ribosome
Translation that happens in the ribosome is located in…
cytosol
Composed of rRNA and proteins
Ribosome
Ribosome shape is determined by what?
rRNA
make proteins. found in cytoplasm/rough ER. Location of translation.
Ribosome
Discrete sites for tRNA binding and polypeptide synthesis.
Ribosome
peptidyl site
P site
aminoacyl site
A site
exit site
E site
Steps of Translation:
1.) Initiation
2.) Elongation
3.) Termination
mRNA is translated at the ribosome into a polypeptide.
Translation
mRNA, tRNA, and the ribosomal subunits form a complex.
Translation-Initiation
The ribosome travels in the 5- to 3’ direction and synthesizes a polypeptide.
Translation-Elongation
The ribosome reaches a stop codon and all of the components disassemble, releasing a completed polypeptide.
Translation-Termination
In eukaryotes, 5’ cap recognized. Initiator tRNA binds to start codon (mRNA).
Translation-Initiation
Aminoacyl tRNA brings a new amino acid to the A site. Binding occurs due to codon/anticodon recognition.
Translation-Elongation
When a stop codon is found in the A site, translation ends. 3 stop codons (UAA, UAG, UGA). Recognized by release factors.
Translation-Termination
___________is directly produced from the transcription of a eukaryotic gene.
A.) rRNA
B.) pre-mRNA
C.) mRNA
D.) DNA
E.) Protein
B.) pre-mRNA
Which of the following statements about RNA polymerase in bacteria is INCORRECT?
A.) It binds the promoter region of a gene.
B.) It is bound to a sigma factor during initiation of transcription.
C.) It synthesizes RNA.
D. It catalyzes the addition of nucleotides to the 5’ end of a growing RNA strand.
E.) It dissociates from the DNA at the terminator.
D. It catalyzes the addition of nucleotides to the 5’ end of a growing RNA strand.
Which of the following would occur if a cell’s spliceosomes were mutated so they no longer functioned normally?
A.) Introns would remain in the mature mRNA.
B.) Exons would be missing in the mature mRNA.
C.) Transcription would cease.
D.) A functional protein would still be produced.
E.) RNA processing would remain intact.
A.) Introns would remain in the mature mRNA.
The relationship between the coding and template DNA strands is complimentary or the same?
complimentary
The relationship between the template DNA strand and the mRNA sequence is complementary or the same?
complimentary
The relationship between the coding DNA strand and the mRNA sequence is complementary or same (with U replacing T)?
same (with U replacing T)
The relationship between mRNA and tRNA is complimentary or the same?
complimentary
The polypeptide sequence is determined from the codon or anti-codon?
codon
