Principle of Biology, Ch.13

The four nucleic acid bases combine in three-letter sequences that define different amino acids.

How is the four-letter language of nucleic acids converted into the 20-word language of amino acids?

translated into the human XYZ protein

If an mRNA transcript of the human XYZ gene was introduced into a yeast cell, the transcript would be:

protects mRNA from degradation

A "5′ cap":

3

In the accompanying figure, the portion of the molecule containing the anticodon is indicated by the label:

3′-GAU-5′

One of the mRNA codons specifying the amino acid leucine is 5′-CUA-3′. Its corresponding anticodon is:

64

The total number of different three-base combinations of the four nucleic acid bases is:

attach to the mRNA molecule and travel along its length to produce a polypeptide

During protein synthesis, ribosomes:

allow the ribosomes to be properly positioned for translation of mRNA molecules.

Leader sequences contain signals that:

the structure of hemoglobin was altered by a mutation of a single gene.

Linus Pauling demonstrated that:

single stranded; uracil

RNA is ____ and contains the nitrogenous base ____, which is absent in DNA.

RNA polymerase

Refer to the accompanying figure. The component labeled as B is:

the attached amino acid.

Refer to the accompanying figure. The portion of the molecule labeled as 5 is:

E

Refer to the accompanying figure. Which label indicates the location of the promoter region?

an extra hydroxyl group

Ribose differs from deoxyribose by having:

tRNA.

The molecule that connects a growing polypeptide chain and mRNA is called:

transcription

The process illustrated in the accompanying figure is:

certain tRNA anticodons can pair with more than one codon sequence

The wobble hypothesis states that:

The first nucleotide retains its triphosphate group, while the others do not.

How does the first nucleotide at the 5′ end of a new mRNA chain differ from the other nucleotides in the chain?

a promoter sequence

Initiation of transcription requires:

transcription.

RNA synthesis is also known as:

adding 100−250 adenine nucleotides

The 3′ end of eukaryotic pre-mRNAs is changed by:

adenine; adenine

Uracil forms a complementary pair with ____ in RNA and ____ in DNA.

It has the ability to bond with adenine.

Which of the following is a characteristic of uracil?

mRNA, tRNA, and rRNA

Which of the following is made from DNA?

Because transcribing both DNA strands would produce different amino acid sequences

Why is only one strand of DNA transcribed into mRNA?