2.6 Transcription & Translation

Which of the following processes involve both DNA and RNA?

I. Replication

II. Transcription

III. Translation

IV. Protein synthesis

The following steps are involved in the process of replicating DNA by polymerase chain reaction (PCR).

1. The temperature is increased to 72°C to allow Taq polymerase to bind to DNA
2. A new complementary strand of DNA is produced 
3. The temperature is raised to 95°C to cause denaturation of the DNA molecule
4. Primers attach to the ends of single strands of DNA by hydrogen bonding
5. The temperature is decreased to about 54°C

Which of the following represents the correct order of the steps?

A short section of mRNA that was produced after transcription occurred has the following base sequence:

AAACUUCUCAUAGAACGG

The following table shows the base sequence for codons and the corresponding amino acids that they code for.

Which of the following would represent the correct amino acid sequence coded for by this section of mRNA?

A polypeptide has the following amino acid sequence:

histidine - glutamine - lysine - alanine - valine - histidine - valine

The table below gives the tRNA anticodons for each amino acid.

A mutation causes the 18^th base in the DNA sequence to be deleted. 

Which of the following would represent the amino acid sequence after this deletion?

What is the correct sequence for the processes involved in the formation of a protein?

Which of the following statements about transcription are true? 

1. DNA remains in the nucleus because it is too large to fit through the pores in the nuclear envelope.
2. Transcription makes a copy of the sense strand of DNA.
3. Transcription converts a sequence of nucleotides into a sequence of amino acids.
4. RNA polymerase forms covalent bonds between the RNA nucleotides.

What terminates the formation of a polypeptide chain during protein synthesis in cells?

In 1957, Meselson and Stahl conducted an experiment that provided overwhelming evidence to support the theory that DNA replication is semi-conservative. They used E. coli which has a generation time of around one hour.

Here are the steps in their experiment in a mixed-up order: 

1. Bacteria contain either all ¹⁴N DNA or hybrid DNA
2. Bacteria grown in a ¹⁵N medium for many generations
3. Bacteria transferred to a ¹⁴N medium and sampled every hour
4. All bacteria contain hybrid DNA (¹⁴N DNA and ¹⁵N DNA).
5. All bacteria contain ¹⁵N DNA

Which is the correct order of the processes?

Which of the following drawings best represents the structure of a section of DNA?

A base substitution mutation has caused a single change to the mRNA transcript of a section of a gene, as shown below. 

Using the table above, what is the change in amino acid sequence caused by this mutation?

Which row of the table contains three correct statements about DNA replication, transcription and translation?

Which of the following statements about the genetic code are correct?. 

1. A single DNA base will always be transcribed and translated in eukaryotic organisms.
2. A single DNA base can be part of genes that overlap each other.
3. The genetic code allows multiple triplet codons to code for a single amino acid. 
4. The genetic code in a eukaryotic organism's genome stays the same throughout the organism's life.

The laboratory technique of Polymerase Chain Reaction (PCR) takes advantage of the ability of polymerase enzymes to copy pieces of genetic material quickly and accurately. Which of the following are necessary for successfully conducting PCR in a forensic examination at a crime scene? 

1. An active sample of human DNA or RNA polymerase
2. Buffer solution
3. A sample of target DNA or RNA
4. Free nucleotides
5. Primer sequences