Biology - gene expression

In a frameshift mutation, nucleotides are added or deleted in any number other than a multiple of -----

three

What role does DNA play in the cell

store genetic information

A(n) ----- mutation is caused by the replacement of one nucleotide with another

substitution

Which of the following best describes translation

the "reading" of an mRNA to produce a protein

In the synthesis of RNA from DNA, the enzyme RNA polymerase adds ----- to the --- end of the growing RNA molecule

Nucleotides 3' prime

True or false: a mutation that occurred in a brain cell due to radiation exposure would be passed to the next generation.

false

Select all of the following agents or processes that can cause mutations

Xrays, radioactivity, UV light, chemicals, or nicotine DNA spontaneously mutate during replication

On one half of a DNA double helix, a single strand of nucleotides has

a 3' end on one side, and a 5' end at the opposite end

on a tRNA molecule, the ----- is a three-base sequence that is complementary to and binds to an mRNA codon during translation

anticodon

A substitution mutation that changes an amino acid into a "stop" codon is called a(n) ---- mutation and shortens the protein product.

nonsense

The ----- is a sequence of DNA that signals the the start of a gene and is the site where RNA polymerase binds to begin transcription

promoter

A change in the amino acid sequence of a protein can cause the protein to be nonfunctional because ----- is affected by the amino acid sequence.

protein folding

IN eukaryotes, what regulatory proteins are required for RNA polymerase to bind to the promoter and initiate transcription?

transcription factors

During the elongation phase of translation, a ---- bond is formed between the incoming ---- acid and the growing polypeptide chain, and empty tRNAs are released from the ribosome to be reused.

- covalent -amino

Wilkins and Franklin performed x-ray diffraction that revealed details about

-Determine the three-dimensional shape of the molecule DNA molecules discovered that DNA was double helix in shape and repeated

Select all of the following that occur during the elongation stage of translation

-Proteins call elongation factors assist in translation elongation -anticodons bind to their complementary codons -amino acids are transferred from tRNAs to a polypeptide chain -Bonds between amino acids are formed

Put in order that they occur during transcription initiation in eukaryotes, beginning with the first step at the top

-The first transcription factor to bind is attracted to a part of the promoter called the TATA box -The TATA binding protein attracts other transcription factors, including proteins bound to an enhancer. -Finally, RNA polymerase joins the complex, binding just in front of the start of the gene sequence.

Select all of the following that are true about Hershey and Chase's experimental design in 1950.

-They used radioactive labels to mark proteins in one set of viruses and to make DNA in another set of viruses -used bacteriophages to infect bacteria in order to determine whether DNA or protein was the genetic information -after infection of the bacteria, they agitated the mixture to separate the viral coats from the bacterial cells

Select all of the following that are true about frameshift mutations

-addition or deletion of nucleotides -often render the resulting protein nonfunctional -THE CAT ATE THE RAT = THE ATA TET HER AT

Select all of the following that are true about frameshift mutations

-can be caused by the deletion of two nucleotides -can be caused by the addition of one nucleotide -likely to change the amino acid sequence -disrupts the codon reading frame

In eukaryotic cells, the mRNA is altered before it leaves the nucleus. A short sequence of modified nucleotides, know as a ---- is added to the 5' end and a string of adenines called a ---- is added to the 3' end.

-cap -poly-A tail

Using synthetic mRNA molecules in test tubes with all the translation machinery, researcher in the 1960s deciphered the ----, which determines what amino acid is specified by each three-nucleotide ---

-genetic code -mRNA codon

Select all the reason a cell regulates gene expression

-helps orchestrate organism development, -to have a specialized function, -to respond to changing conditions

Select all of the following that are true about prokaryotic versus eukaryotic gene expression

-in eukaryotes, the nuclear membrane separate transcription from translation -in eukaryotes, mRNA is altered before it leaves the nucleus

Select all of the following that are present in bacterial operon.

-operator -promoter -group of genes

select ways that cells increase the speed of protein synthesis

-produce multiple copies of each mRNA -multiple ribosomes simultaneously translate an mRNA

Select all of the following that are true about E. coli bacteria in an environment lacking lactose

-repressor binds to the operator, preventing expression of lactose-digesting enzymes -The three genes of the lac operon are not transcribed

Select all of the following that are utilized in the process of translation

-ribosomes -mRNA -rRNA -tRNA -Amino acids

AN anticodon is a sequence found on a(n) ----- molecule, whereas a codon is a sequence found on a(n) ----- molecule

-tRNA -mRNA

Transciption

1 - initiation: enzymes unzip DNA, and RNA polymerase binds to the promoter 2 - elongation: moving from 3' to 5' along the template strand, RNA polymerase adds complementary nucleotides to a growing RNA strand 3 - Termination: RNA polymerase reaches the terminator sequence and detaches from DNA and from the RNA molecule

Match mutation types with description missense nonsense frameshift silent

1 - mutation that results in the change of a codon for one amino acid into a codon for another amino acid 2- a base triplet specifying an amino acid changes into one that encodes a "stop" codon 3- adds or deletes nucleotides in any number other than a multiple of three 4- the mutated gene encodes the same protein as the original gene version

Frederick Griffith Oswald Avery, Colin MacLeod, and Maclyn McCarty Hershey and Chase Archibald Garrod

1 -contributed the first step in identifying DNA as the genetic material; discovered that one strain of bacteria could "transform" another by inducing it to display new traits. 2- finally learned the identity of the "transforming principle." The researchers treated heat-killed type S bacteria with a protein-destroying enzyme and mixed them with live type R bacteria 3-demonstrated that radioactively-labeled DNA, not protein, entered bacterial cells and riected them to produce viruses 4-Discovered that people with "inborn errors of metabolism" lacked certain enzymes

What represents Chargaff's discovery about the amounts of the nitrogenous bases A, G, C, and T in the DNA molecule?

Amount of A = T Amount of C = G

During transcription, RNA nucleotide bases bind with the exposed complementary bases on the template strand of

DNA

The information that each cell needs to produce proteins is stored in a molecule called

DNA

Match eukaryotic regulatory mechanism with where it would act within the "central dogma" DNA availability mRNA processing, mRNA exit from the nucleus protein degradation transcription factors

DNA availability- Occurs before transcription. mRNA processing, mRNA exit from the nucleus- Occurs after transcription but before translation. Protein degradation- Occurs after translation. Transcription factors- Occurs at initiation of transcription.

Select all of the types of protein modification that can occur after translation to produce a functional protein

Enzymes cut proinsulin to form insulin. A different type of modification occurs when polypeptides join to form larger protein molecules.

Modification to DNA, such as methylation, that do not change the nucleotide sequence but do affect gene expression are called ----- modifications

Epigenetics

True or false: in the 1940s, Avery, McCarty, and MacLeod figured out that the "transformation principle" from Griffith's experiments was actually protein.

FALSE: DNA from type S cells altered the type R bacteria, enabling them to manufacture the smooth coat necessary to cause infection.

True or false: Since the nineteenth century, scientists have known that DNA is the molecule of heredity.

False: was not until 20th

Select all for the correct statements regarding the results of Frederick Griffith's 1928 experiment involving Streptococcus pneumoniae.

Griffith found that heat-killed type S bacteria did not cause pneumonia in mice. However, when he injected mice with a mixture of live type R bacteria plus heat-killed type S bacteria, neither of which could cause pneumonia alone, the mice died. Moreover, their bodies contained live type S bacteria encased in polysaccharide. Something in the heat-killed type S bacteria transformed the normally harmless type R strain into a killer. Type R bacteria, named for their "rough" colonies, do not cause pneumonia when injected into mice. Type S ("smooth") bacteria, on the other hand, cause pneumonia.

What is one major difference between eukaryotes and prokaryotes with respect to translation?

In prokaryotes, translation can take place even before transcription is complete

Place the following events in order from occurring first to occurring last in the production of albumin, a milk protein

Inside the nucleus, an enzyme first transcribes the albumin gene's DNA sequence to a complementary sequence of RNA. RNA moves into the cytoplasm AMino acids area assembled into a protein

----- in DNA may arise spontaneously as errors in replication, or they can be induced by external agents, like chemicals and radiation

Mutation

A(n) _____ is a change in a cell's DNA sequence.

Mutation

Select all the reasons why the polypeptide product of translation may be nonfunctional

Proteins can fold incorrectly if the underlying DNA sequence is altered, because the encoded protein may have the wrong sequence of amino acids

Gene expression is the production of a functional ----- or a ----.

RNA molecule protein

During transcription, what reads the template strand within a gene and adds complementary bases?

RNA polymerase

In transcription, a(n)----- molecule is produced from the information that is encoded in a(n) ------ molecule

RNA, DNA

Statements about nucleotides that are accurate

Three parts: phosphate, a 5-carbon sugar, and a nitrogen containing base. Building block of nucleic acids DNA

What scientists worked out the double helical structure of DNA using a ball-and-stick model.

Watson and Crick used data on the structure of DNA to build the first DNA model. Model showed a double helix of two strands of nucleotides, each with sugar-phosphate backbones and a nitrogenous base Complementary base pairing holds the two strands together.

nucleotides

are the building blocks of nucleic acids

Roles that microRNAs play in regulating gene expression

cause mRNA to be degraded bind to mRNA and prevent translation

In an RNA molecule, a(n) --- is a genetic "code word" that corresponds to one amino acid

codon

Withing the DNA double helix, the so-called backbone is composed of ----- sugars alternating with phosphate groups

deoxyribose

In eukaryotes, transcription factors can bind at near or distant regulatory DNA sequences called

enhancers

---- are portions of mRNA that get spliced together to form mature mRNA prior to translation

exons

Hershey and Chase experiment, radioactively-labeled sulfur was found in the ______ within one test tube, while radioactively-labeled phosphorus was found in the ______ within the other test tube, indicating that _______ was the genetic material

fluid; bacteria cells, DNA

All of the genetic material that is within a cell is called its

genome

A(n) ----- mutation is one that occurs in the cells that give rise to sperm or egg

germline

A(n) ------ is a portion of RNA that averages about 1,000 nucleotides long and that is removed before translation

intron

Transcription of the three genes in the lac operon occurs when

lactose is present in the environment and binds to the repressor.

During production of a protein, the information encoded in a DNA base sequence is transcribed to produce a molecule of ----, which is then processed and translated to produce the sequence of ----- acids in a protein.

mRNA amino

Match each type of RNA with its correct description

mRNA - carries the information that specifies a protein tRNA - connector molecule that binds to an mRNA codon and to an amino acid rRNA - ribosomal RNA: structural component of the ribosome

During the elongation stage of translation, the ribosome exposes codons on the ----- one at a time; each codon determines what ----- will bring its attached amino acid to the ribosome to be added to the polypeptide chain.

mRNA; tRNA

In bacterial operons, a DNA sequence that exists between the promoter and the protein coding region is called the ---- and is where a repressor protein can bind

opterator

During the Hershey-Chase experiment, radioactive ---- was used to label the DNA, and radioactive ---- was used to label the protein.

phosphorus; sulfur

Enzymes and chaperone proteins assist in ---- that takes place after translation is complete

polypeptide folding

During translation, a(n) ----- is produced from the information that is encoded in a(n) ----

protein; RNA molecule

IN the Hershey and Chase experiment, ----- was found inside the infected bacteria indicating that the labeled viral ----- had entered the bacterial cells to direct new virus production

radioactive phorsphorus; DNA

A complex of rRNA and proteins called a(n) --- is the physical location of protein synthesis

ribosome

Select all of the following that are genes

sequence of DNA nucleotides that codes for a specific protein sequence of DNA nucleotides that codes for a specific RNA molecule

A mutation that causes an mRNA nucleotide to change from GGC to GGA is a --- mutation

silent

In the "central dogma" describing the flow of genetic information from DNA to protein, DNA is copied to RNA in a process called -----, and the information in RNA is used to direct the synthesis of a protein in a process called ---

transcription, translation

In eukaryotic cells, proteins called ----- factors bind at specific DNA sequences, which allows RNA polymer

transcriptions