MCB 181 Exam 2 UofA

T/F the primary structure of a protein determines its function

true

T/F the amino acid leucine would likely be buried within the core of a folded protein in water

true

T/F a single point mutation in a gene is not sufficient to change the structure and function of the protein that gene codes for

false

T/F some types of RNA behave similarly to proteins - for example, by catalyzing reactions of transporting molecules within the cell

true

T/F the process of transcription, translation and splicing all involve RNA

true

T/F during transcription, incoming RNA nucleotides are added to the 5' end of the growing RNA strand

false

T/F The specificity of codon-anticodon interaction during translation depends on complementary base pairing between nucleotides

true

T/F during transcription, RNA is transcribed from the coding DNA strand

false

T/F A synonymous mutation in the DNA will likely be able to produce a functional protein

true

T/F In the Cell Cycle, DNA replication takes place during interphase

true

T/F DNA polymerase can initiate the synthesis of a new DNA strand on its own

false

T/F due to its antiparallel nature, DNA must be synthesized in the 5' to 3' direction on the leading strand and the 3' to 5' on the the lagoon strand

false

T/F an uncorrected error that occurs once during translation will likely affect and organism more than an uncorrected error that occurs once during DNA replication

false

the secondary structure of a protein is mainly stabilizes by which of the following?

hydrogen bonds

amino acids are held together by which type of bond?

peptide bond

which amino acid would be found inside a protein channel

serine

which amino acid would be found inside of the cell in the nucleus

glutamine

which interactions help to stabilize the double helix structure of DNA?

phosphodiester and hydrogen bons

DNA sample contains 20% cytosine, what percent of the DNA is made up of adenine?

30%

Why does a gene in the DNA need to be transcribed into RNA in order to make a protein?

RNA can be edited and can travel out of nucleus to translation site

during transcription, RNA polymerase does which of the following

unwind DNA double helix, stabilize DNA and RNA during transcription, form bond for RNA nucleotides, rewind DNA double helix

what mutations stops genes encoding actin from being transcribed?

mutation is promoter of actin gene, or mutation is transcription factor for actin gene

which process allows one gene to code for multiple different proteins?

alternative splicing

elongation of translation

antibiotics block A site on bacterial ribosomes

single nucleotide substitution in DNA leading to nonsense mutation would result in what?

a shortened protein

which of the strands use a template for DNA replication

both leading and lagging

which function does DNA polymerase perform?

synthesizing DNA, proofreading DNA nucleotides

T/F each amino acid has only a single codon that codes for it

false

what is believed to have come first in evolution of life

RNA, able to encode info and protein like function

why is lagging strand necessary in DNA synthesis

DNA is antiparallel and DNA polymerase can only synthesize DNA in 5' to 3' direction

polymer definition

many monomers bonded together through polymerization

protein _ determine protein _

shape, function

amino acid composed of;

carbon atom, amino group, carboxyl group, R group, hydrogen

peptide bond

covalent bond between amino acids

polypeptide

immature protein; many amino acids linked

primary structure definition

sequence of amino acids that make up polypeptide strand

secondary structure function

stabilize with H-bonds on polypeptide backbone

secondary structure components

alpha helix and beta sheets

alpha helix

carboxyl group of amino acid, forms h-bond with amide group

beta sheets

polypeptide bends, parallel strands, hydrogen bonds form with carbonyl and amide

what is secondary structure result of?

hydrogen bonding along backbone, forms alpha helices or beta sheets

tertiary structure components

several secondary structures

what is tertiary structure resulted from?

interactions between R groups, water or polypeptide

quaternary structure

interactions of 2 or more ternary polypeptides; mature protein

what determines proteins function

tertiary structure; folding

what is goal of central dogma

create protein

DNA main functions

store genetic info, copying itself

DNA

master copy of protein blueprints

RNA

editable copy of protein blueprints

Protein

new language from genetic code to amino acids; by ribosomes

DNA to RNA

transcription

RNA to protein

translation

nucleic acids

DNA and RNA

pyrimidines

single ringed; cytosine, thymine, uracil

purines

double ringed; guanine, adenine

how are nucleotide monomers bonded

phosphodiester bonds

nucleic acid polymer

hydroxyl group attached to 3' carbon of phosphate group attached to 5' carbon

transcription function

gene code transcribed into mRNA

DNA used as template for...

complementary strand of RNA

gene of interest

DNA is unwound

antiparallel to gene of interest is...

template for RNA transcript

DNA with gene of interest is...

nontemplate

RNA transcript

RNA nucleotides polymerized by RNA polymerase

RNA reads in

5' to 3'

RNA built in

5' to 3'

where does transcription take place

nucleus of eukaryote or cytoplasm of prokaryote

initiation of transcription

RNA polymerase and transcription factors bind

promoter

contains TATA sequence, RNA polymerase recognizes and binds

mediator complex

forms when; transcriptional activator proteins bind to the enhancer sequences

mediator complex binding sites

RNA polymerase, enhancer transcription factors, promoter transcription factors

elongation

in prokaryotes; RNA polymerase

RNA polymerase function in elongation

unwinding of DNA, stabilize DNA-RNA pairing, channel in free nucleotide bases, catalyze phosphodiester bonds, restore double helix

termination

after initiation & elongation; poly A single sequence recognized by RNA polymerase

DNA read...

3' to 5'

RNA transcribed...

5' to 3'

what processes happen simultaneously in prokaryotes

translation and transcription

what must happen in eukaryotes before translation

mRNA must be processed and transported to cytoplasm

RNA process steps

1) nucleotide cap added to 5' end 2) polyA tail added to 3' end 3) introns spliced out

5' cap function

gives mRNA stability, recognition site for ribosomes to bind

3' polyA tail function

gives mRNA stability, recognition site for exporter proteins to bind

exon function

primary RNA coding region

intron function

primary RNA non-coding regions

splicing

introns removed from RNA transcript and exons join together

spliceosome

protein that splices out introns

alternative splicing

single gene is edited to make different proteins

what info does mature mRNA carry

info for protein within its nucleotide sequence

to make a protein, nucleotide sequence is translated to what?

amino acid sequence

genetic code

read 3 nucleotides at once (codon)

codon

3 nucleotides that are translated to specific amino acid

stop codon

AUG

start codon

UAA, UGA, UAG

transfer RNA form

single stranded, non-coding, base pairs with self

transfer RNA function

carries amino acids to ribosome

anticodon loop

reads codons in mRNA through complementary base pairing

how do codons and anti-codons interact?

the anticodon of tRNA base pairs with complementary codon on mRNA

aminoacyl tRNA synthetase

enzyme that translates genetic code to amino acid

aminoacyl tRNA synthetase function

binds to specific amino acid, formation of bond between amino acid & tRNA

ribosome function

mRNA moves through center of ribosome and ribosome reads mRNA 5' to 3' in codons

A site

aminoacyl tRNA site in ribosome

P site

peptide bond form between amino acids in ribosome