Bio Final

Which of the following processes only occurs in eukaryotic gene expression?

A poly-A tail is added to the 3' end of an mRNA, and a cap is added to the 5' end.

____________ are changes in the DNA and often lead to faulty proteins that can be life threatening.

Mutations

RNA viruses tend to have unusually high rates of mutation because Replication of their genomes does not involve ______in genome replication.

correcting errors

A particular triplet of bases in the template strand of DNA is 5'-AGT-3'. The corresponding codon for the mRNA transcribed is

3'-UCA-5'.

DNA and RNA are synthesized in a ________ direction.

5' to 3'

In which direction does RNA polymerase move along the DNA?

5' to 3' end along the template strand

The genetic code is essentially the same for all organisms. Based on this information, one can logically assume which of the following statements to be correct?

A gene from an organism can theoretically be expressed by any other organism.

The nitrogenous base adenine is found in all members of which of the following groups of molecules?

ATP, RNA, and DNA

A part of the promoter, called the TATA box, is said to be highly conserved in many different organisms through evolution. Which of the following correctly describes why this is the case?

Any mutation in the sequence is selected against.

A gene is a ________________ sequence that is expressed to form a functional product, either _________ or _________________

DNA; RNA or polypeptide

Modifications to the mRNA such as a poly-A tail added to the 3' end of an mRNA, and a cap added to the 5' end are only found in :

Eukaryotes

___________________ is the process by which DNA directs the synthesis of proteins.

Gene expression

What is the function of reverse transcriptase in retroviruses?

It uses viral RNA as a template for DNA synthesis.

____________________ is sequencing DNA from a group of species from the same ecosystem

Metagenomics

____________ are credited for doing the major work of the cell while DNA (genes) is the instructions describing how to make them.

Proteins

In eukaryotes there are several different types of RNA polymerase. Which type is involved in transcription of mRNA known as pre-mRNA?

RNA polymerase II

Alternative _____________________ allows the production of different protein products from a single mRNA.

RNA splicing

_______________ initiate the splicing of the pre-mRNA used in the process of cutting out introns.

Spliceosomes

The ________ box is the recognition site for a specific transcription factor.

TATA

What characteristic of short tandem repeat DNA makes it useful for DNA fingerprinting?

The number of repeats varies widely from person to person or animal to animal.

Three steps for the order of events in a generalized viral replicative cycle?

The virus enters the cell, host enzymes replicate the viral genome, enzymes transcribe the viral genome into mRNA.

When the genome of a particular species is said to include 20,000 protein-coding regions, what does this imply?

There are also additional genes for RNAs other than mRNA.

How do antiviral drugs help to treat viral infections?

They interfere with viral replication.

Fragments of DNA have been extracted from the remnants of extinct woolly mammoths, amplified, and sequenced. How might these fragments be used now?

They may help us to understand the evolutionary relationships among members of related organisms.

__________ in eukaryotes requires several transcription factors in addition to RNA polymerase.

Transcription

A particular triplet of bases in the coding sequence of DNA is AAA. The anticodon on the tRNA that binds the mRNA codon is

UUU

In the 1920s, Hermann Muller discovered that X-rays caused genetic changes in the fruit fly Drosophila. In a related series of experiments in the 1940s, other scientists discovered that other types of chemicals have a similar effect. A new chemical food additive is developed by a cereal manufacturer. Why is it necessary to test for its ability to cause mutation?

We want to prevent any chance that it might cause mutations.

The most commonly occurring mutation in people with cystic fibrosis is a deletion of a single codon. What is the most likely result of this mutation in the protein product?

a polypeptide missing an amino acid

____________ is the application of computational methods to the storage and analysis of biological data

bioinformatics

How do small RNAs in the spliceosome initiate the splicing of the pre-mRNA?

by binding to the 3'end of the pre-mRNA and removing the poly-A tail

Garrod developed the "one _____, one _____" concept. He hypothesized that genes coded for ________, and if the gene is bad, the ________ will be bad.

gene, enzyme ; enzymes, enzyme

Garrod hypothesized that inherited diseases such as alkaptonuria, the inability to metabolize the chemical alkapton, occur because

genes dictate the production of specific enzymes, and affected individuals have genetic defects that cause them to lack certain enzymes.

If the TATA box is mutated then transcription and translation would be:

greatly reduced or eliminated

Viruses cannot replicate without a ____

host cell

_____________ or ______________ of a base (a mutation) could result in a frameshift mutation.

insertion or a deletion of a base

Noncoding sequences are called _______

introns

The effect of a _______________ substitution introduces a premature stop codon into the mRNA and results in a __________ mutation

nucleotide-pair ; nonsense

Bacteria have _______ (#) type(s) of RNA polymerase, whereas eukaryotes have at least ______.

one, three

In the lysogenic cycle of lambda (λ) phage the _________________ replicates along with the ___________

phage genome ; host genome.

In mRNA the ____________, protects the mRNA from degradation by hydrolytic enzymes.

poly-A tail

Genetic variation among humans is relatively small when compared to other species. It occurs most in single nucleotide _______________

polymorphisms

RNA polymerase II is involved in transcription of a type of mRNA known as :

pre-mRNA.

The process of translation in both prokaryotes and eukaryotes requires tRNAs, amino acids, and ribosomal subunits. Which of the following components must also be present for translation to proceed?

protein factors and GTP

_________ is the study of the full protein set encoded by a genome

proteomics

In viruses, RNA is used to build DNA using an enzyme known as ______

reverse transcriptase.

One of the first events in translation is a small subunit of the ____________ recognizing and attaching to the ________ end of mRNA

ribosome ; 5' end

A ___________ is an RNA with enzymatic activity.

ribozyme

In order for protein synthesis to occur, ___________ must be charged with the correct amino acids.

tRNA

One of the primary reasons viruses are considered non-living is because :

viruses cannot reproduce outside of a living cell.