Bio Chapter 7

Order of translation initiation and elongation events

1. The 5' end of the mRNA molecule binds with the small ribosomal subunit. 2.tge first tRNA binds to the start codon on the mRNA molecule 3. The large ribosomal subunit brings to the small ribosomal subunit 4.the second tRNA molecule brings to the second codon on the mRNA molecule 5.a covalent bond is formed between two amino acids 6. The ribosome releases an empty tRNA

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

1.the theee genes of the lac operon are not transcribed 2. The repressor binds to the operator of the lac operon

The term genome refers to

All the genetic material in an organisms cell

What 3-vase site of tRNA molecule is complementary to an mRNA codon ?

Anticodon

These are True about genetic code

Aug encodes methionine and start There are three codons that act as a stop codons The same genetic code is used by nearly all species

tRNA role in translation

Contains an anticodon on one end that determines what amino acid binds to the other end

mRNA role in translation

Contains codons specifying the order of amino acids

eukaryotic and prokaryotic

Controlling access to a promoter Proteins that bind to regulatory sequences with DNA

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

DNA

Hershey and chase

Discovered that DNA contains genetic information rather than protein

Griffith's experiment

Discovered that DNA is transmitted between toxic and harmless bacteria

DNA has a ___ helical structure consisting of two intertwining strands of __

Double; nucleotides

RNA ploymerase moves down the template strand, adding nucleotides and producing a complementary RNA molecule

Elongation

Eukaryotic cells

Enhancers Adding methyl groups to silence genes Blocking mRNA exit from the nucleus

Heritable modifications to DNA such as methylation that do not change the nucleotide sequence but do affect gene expression are called ___ modifications

Epigenetic

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

Exons

Adds or deletes nucleotides in any number other than a multiple of three

Frameshift

RNA polymerase binds to the genes promoter

Initiation

In eukaryotes and arches, a part of an mRNA molecule that is removed before translation is called an

Intron

rRNA role in translation

Major component that makes up the structure of a ribosome

Mutation that results in the change of a codon for one amino acid into a codon for another

Missense

Mutation that results in the creation of a stop codon

Nonsense

At the beginning of transcription which of the following does RNA polymerase bind to ?

Promoter

In transcription an ____ molecule is produced from the information that is encoded in an __ molecule

RNA . DNA

the enzyme that builds the RNA chain during transcription

RNA polymerase

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 phosphorus; DNA

A complex of RNA and proteins called a ____ is the physical location of protein synthesis

Ribosome

Mutation that encodes the same protein as the original gene version

Silent

These can cause mutations

Some forms of radiation Chemical mutagens Errors in DNA replication

These are true about codons

TRNAS have specific complementary sequences that bind to them They are composed of three mRNA bases.

RNA polymerase separates from the DNA and the newly synthesized RNA is released

Termination

What best describes translation?

The "reading" of an mRNA to produce a protein

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

Three

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

Transcription factors

In the Hershey and chase experiment, radioactively labeled sulfur was found in the _ within one test tube, while radioactively phosphorous was found in _ within the other test tube, indicating that _ was the genetic material

fluid; bacterial cells; DNA