Bio CH 17

Look at the table: Which of the following sequences of nucleotides are possible in the template strand of DNA that would code for the polypeptide sequence: Phe-Leu--IIe-Val?

3'-AAA-GAA-TAA-CAA-5'

Look at table of codons: Which of the triplets below is a possible anticodon for a tRNA that supports proline to a ribosome?

3'-GGC-5'

Use the following information to answer the question. A part of an mRNA molecule with the following sequence is being read by a ribosome: 5 ȝ-CCG-ACG-řȝ (mRNA). The following charged transfer RNA molecules (with their anticodons shown in the 3ȝ to 5ȝ direction) are available. Two of them can correctly match the mRNA so that a dipeptide can form.

3'-GGC-5'

A particular triplet of bases in the template strand of DNA is 5ȝ-AGT-řȝ. What would be the corresponding codon for the mRNA that is transcribed?

3'-UCA-5'

The genetic code is essentially same for all organisms. From this one can logically assume which of the following statements to be true?

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

During the elongation phase of translation, which site in the ribosome represents the location where a codon is being read?

A site

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

AAA

Which one of the following structures, if missing, would usually prevent translation from starting?

AUG codon

Codons are three-base sequences in mRNA that specify the addition of a single amino acid to the growing protein chain during translation. How do eukaryotic codons and prokaryotic codons compare?

Codons are a nearly universal language among all organisms.

Once researchers identified DNA as the molecule responsible for transmitting heritable traits, they asked how information was transferred from the DNA in the nucleus to the site of protein synthesis in the cytoplasm. Which of the following statements correctly describes the mechanism of information transfer in eukaryotes that accomplishes this task?

Messenger RNA is transcribed from a single gene and transfers information from the DNA in the nucleus to the cytoplasm, where protein synthesis takes place.

The genetic code is redundant. What is meant by this statement?

More than one codon can specify the addition of the same amino acid.

The tRNA shown in the figure has its 3ȝ end projecting beyond its 5ȝ end. Which of the following processes will occur at this 3ȝ end?

The amino acid binds covalently.

In bacteria, there are 61 mRNA codons that specify an amino acid, but only 45 tRNAs. Which of the following statements explains this fact?

The rules for base pairing between the third base of a codon and tRNA are flexible.

Which of the following processes is the first event to take place in the translation of eukaryotes?

The small subunit of the ribosome recognizes and attaches to the 5' cap of mRNA.

Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on specificity in the

binding of the anticodon to the codon and the attachment of amino acids to tRNAs.

What type of bonding is responsible for maintaining the shape of the tRNA molecule shown in the figure? Look at figure in 16

hydrogen bonding between base pairs

According to the central dogma, what is the intermediate molecule involved in the flow of information in a cell that should go in the blank? DNA → ________ → Proteins

mRNA

Which of the following molecules are required for the process of translation?

mRNA, tRNA, and rRNA

Use the following information to answer the question. A part of an mRNA molecule with the following sequence is being read by a ribosome: 5 ȝ-CCG-ACG-řȝ (mRNA). The following charged transfer RNA molecules (with their anticodons shown in the 3ȝ to 5ȝ direction) are available. Two of them can correctly match the mRNA so that a dipeptide can form. (look at the table)

proline-threonine

Look at the table: What amino acid sequence would be generated, based on the following mRNA codon sequence? 5'-AUG-UCU-UCG-UUA-UCC-UGG-3'?

wrong

What type of bonding is responsible for maintaining the shape of the tRNA molecule shown in the figure?

śȝ-UUC-řȝ 7