DNA_Long2

Set 1

Set 2

Set 3

Set 2

Choose

The following questions are based on PROTEIN SYNTHESIS.

Question 1

1.1 Define each of the following:

1.2 The sequence of nitrogenous bases on a DNA strand that codes for part of a protein molecule is shown below:

GTC — TTG — AGT

Using the DNA sequence write down the m-RNA sequence that reads from L to R. (3)

C A G --- A A C --- U C A (in sequence)

Transcription (2)

Synthesis of mRNA from a DNA template/by complementary matching of the nitrogenous bases in DNA.

Translation (2)

The process of converting the information carried by mRNA to the correct sequence of amino acids to form a particular protein.

1.3 The following diagram shows the anticodons of nine different t-RNA (transfer RNA) molecules each carrying a particular amino acid.

Using the above information write down the amino acids (in the correct sequence) that would be required for the base sequence of m-RNA shown alongside. (3)

Serine; Alanine; Valine. (in sequence)

UCA — CGU — CAA

1.4 Study the diagram below then answer that questions that follow:

Identify the nucleic acid above, and give TWO reasons for your answer. (3)

RNA

Reason 1: Single stranded.

Reason 2: Presence of Uracil

Name the parts numbered 1 and 2 on the diagram above. (2)

1: Phosphate ion

2: Ribose sugar

Question 2

2.1

Name the process occurring at A (1)

Transcription

Name the process occurring at B (1)

Translation

Identify organelle C (1)

ribosome

Explain how the m-RNA is made from the DNA template during process A. (5)

The process is called transcription.

Free nucleotides from the nucleoplasm arrange themselves complementary to the base sequence on the DNA template.

Adenine will arrange itself opposite thymine, uracil opposite adenine, cytosine opposite guanine and guanine opposite cytosine.

Sugar-phosphate bonds form between nucleotides to form the mRNA.

The process is controlled by enzymes.

Study the diagram below then answer the questions that follow.

2.2 Processes A and B above are summarised by the table below.:

Nitrogen bases are represented by numbers 1, 2 and 3. Name (say it out aloud) each of the nitrogen bases, in the correct order. (3)

AGG

UCC

CGT

Questions source: DBE (Authorisation 11798)

- Greg Gopaul -