bio test 3 chapter 12

A fourth type of RNA, called _____, is used in the silencing of some genes.

siRNA

After RNA polymerase builds the mRNA strand, transcription is terminated when RNA polymerase encounters a ____ signal at the end of a gene.

stop

The molecule that carries each amino acid to its correct position along mRNA in the cytoplasm is:

tRNA

_____ brings amino acids to the ribosome complex for protein synthesis.

tRNA

When mRNA leaves the cell's nucleus, it next becomes associated with:

a ribosome

Operons are found in eukaryotes but not in prokaryotes.

false

Processing of eukaryotic mRNA occurs in the cytoplasm prior to translation.

false

The codon of tRNA is complementary to the anticodon of mRNA.

false

The first amino acid enters through the A site.

false

The synthesis of messenger RNA is called translation.

false

The three nucleotide sequence on mRNA is called an anticodon.

false

When RNA polymerase reaches a specific sequence of nucleotides on the DNA called the transcription terminator, a hairpin loop structure forms on the DNA strand causing the RNA polymerase and mRNA to dissociate from the DNA.

false

A group of DNA nucleotides that contains the information to produce a single protein is a:

gene

The use of DNA information to direct the production of particular proteins is called:

gene expression

This is followed by the removal of_____ from the primary mRNA transcript, which results in the joining of the _____

introns exons.

The RNA copy of DNA that leaves the nucleus and travels to the cytoplasm to make proteins is:

mRNA

_______ is a transcript of a DNA template and is responsible for carrying genetic information encoded by DNA to the ribosomes for protein synthesis to occur.

mRNA

Both DNA and RNA are _____ comprised of nucleotides.

nucleic acids

DNA is localized to the ____, while RNA can also be found in the cytoplasm.

nucleus

In eukaryotes, transcription takes place in the _________ and translation takes place in the ________.

nucleus, cytoplasm

1. DNA in nucleus serves as a template for mRNA 2. mRNA is processed before leaving the nucleus 3. mRNA moves into cytoplasm and becomes associated with ribosomes 4. tRNAs with anicodons carry amino acids to mRNA 5. anticodon-codon complementary base pairing occurs 6. polypeptide synthesis takes place one amino acid at a time

order to represent the process involved in eukaryotic protein synthesis

On the other hand, DNA contains a sugar lacking an atom of _____.

oxygen

Finally, both molecules contain a backbone made of bonded sugar and ______ molecules.

phosphate

Amino acids are joined to build a ________ until a stop signal on the mRNA terminates translation.

polypeptide

The site where RNA polymerase attaches to the DNA molecule to start the formation of mRNA is called a(n):

promoter

The segment of the DNA molecule where messenger RNA synthesis begins is called the

promoter region

For a gene to be transcribed, the RNA polymerase has to bind to a(n) _____ sequence of nucleotides on the DNA.

promotor

Which of the following cannot be a product of transcription?

protein

Translation is the synthesis of

proteins from mRNA

Several segments of _____ join with proteins to form ribosomes, organelles used in the synthesis of proteins.

rRNA

Translation of the mRNA begins when the _______ recognizes a _____sequence on the mRNA.

ribosome start

Splicing joins together

2 exons

There are _____ major types of RNA, each with a specific function in this process

4

Translation is terminated when a stop codon is presented at the ________ site.

A

All of the following occur in both prokaryotes and eukaryotes except: A. there is DNA transcription B. there is alternative splicing of genes C. in RNA, uracil replaces thymine D. translation occurs on a ribosome E. tRNA carries the amino acid to the mRNA to make polypeptides

B.

Which of the following statements about eukaryotic mRNA is TRUE? A. a cap is added to their 5' end B.a poly-A tail is added to their 3' end C. each usually specifies only a single protein. D. A and B E. A, B, and C

E

How is it possible for a single gene to encode more than one polypeptide?

Exons in mRNA can be spliced together in different combinations.

RNA is important to biological cells because it allows protein synthesis to occur according to the genetic instructions encoded in ____

DNA

Which of the following best describes transcription?

DNA -> RNA

The complementary messenger RNA strand that would be synthesized from the DNA base sequence of CTGAC would be

GACUG.

Which of the following best describes translation?

RNA -> Protein

Transcription is initiated when an enzyme called _____ binds to a special nucleotide sequence on the DNA called a _______

RNA polymerase promoter

Which of the following occurs as the ribosome shifts down the mRNA by a distance of three nucleotides?

The tRNA that was in the P site moves into the E site.

Due to _________, the 25,000 genes of the human genome seem to encode as many as 120,000 different expressed mRNAs.

alternative splicing

In some cases, however, cells do not use all exons present to form a mature mRNA transcript, and instead use a process called ________ to increase the number of unique proteins made from a single gene.

alternative splicing

Which of these events occur as a prokaryotic mRNA is being transcribed?

binding of ribosomes

Nucleotides are the building blocks of

both DNA and RNA.

The first step in this process is the addition of a 5'_____ and a 3' ______l, which is comprised of a series of adenine nucleotides.

cap poly-A tai

In_______ cells, mRNA is transcribed from DNA in the nucleus. Before entering the ______, however, the _____ mRNA transcript must undergo processing to become a mature mRNA transcript.

eukaryotic cytoplasm primary

The nucleotide sequences on DNA that actually have information encoding a sequence of amino acids are:

exons

In _____, mRNA is synthesized from DNA.

transcription

In _____, a polypeptide is synthesized using instructions in the mRNA.

translation

The process of bringing in the appropriate amino acid into position along the mRNA in the cytoplasm is:

translation

A structural gene encodes the information for a specific protein.

true

Synthesis of a new strand of messenger RNA is in the 5' to 3' direction.

true

The amino acid sequence of a protein determines its shape and specific function.

true

The bases of RNA are the same as those of DNA with the exception that RNA contains:

uracil instead of thymine

RNA contains a unique nitrogenous base called _____

uracil.