Mastering Biology CH 17

Given a DNA molecule with the sequence of bases 5'-ATTGCA-3', what would be the sequence of the complementary strand? (It will be helpful to draw the DNA molecule when answering the question.)

3'-TAACGT-5'

Which one of the following statements is true of tRNAs?

Each tRNA binds a particular amino acid.

What enzyme catalyzes the attachment of an amino acid to tRNA?

aminoacyl-tRNA synthetase

What is a ribozyme?

biological catalysts that are RNA molecules

Which of the following terms best describes the relationship between the newly synthesized RNA molecule and the DNA template strand?

complementary

The anticodon of a particular tRNAtRNA molecule is

complementary to the corresponding mRNA codon

What happens to RNA polymerase II after it has completed transcription of a gene?

The enzyme is free to transcribe other genes in the cell.

How is translation initiated?

The small ribosomal subunit binds to the mRNA.The tRNA bearing methionine binds to the start codon.The large ribosomal subunit binds to the small one.The start codon signals the start of translation.

DNA does not store the information to synthesize which of the following?

organelles

Transcription begins at a promoter. What is a promoter?

site in DNA that recruits the RNA Polymerase

Where does RNA polymerase begin transcribing a gene into mRNA?

nucleotide sequence called a promoter

Which of the following statements best describes the promoter of a protein-coding gene?

the promoter is a nontranscribed region of a gene

In eukaryotic cells, transcription cannot begin until

the two DNA strands have completely separated and exposed the promoter.

A codon consists of __________ bases and specifies which __________ will be inserted into the polypeptide chain.

three, amino acid

What is the process called that converts the genetic information stored in DNA to an RNA copy?

transcription

Which of the following clues would tell you if a cell is prokaryotic or eukaryotic?

whether or not a cell is partitioned by internal membrane will be one of the major characteristics to differentiate between prokaryote and eukaryote

What determines which base is to be added to an RNA strand during transcription?

Base pairing between the DNA template strand and the RNA nucleotides

After an RNA molecule is transcribed from a eukaryotic gene, what are removed, and what are spliced together, to produce an mRNA molecule with a continuous coding sequence?

Introns, intervening sequences, are removed and the exons, expressed sequences, are spliced together.

Your body contains tens of thousands of different proteins, each with a specific structure and function. The unique three-dimensional shape of each of these diverse proteins is based on several superimposed levels of structure. Which of the following is an accurate statement about proteins?

The primary structure of a protein is the order of amino acids in a polypeptide, as coded for in the DNA of a gene.The order of DNA nucleotides in a gene provides the code for the specific order of amino acids in the primary structure of a protein