Nucleic acids (parts of the specification missed)

Question 1

Draw a representative diagram of the replication fork (with a small number of nucleotides).

Answer 1

Look at textbook

Question 2

Three bases coding for an amino acid are called what in DNA and what in mRNA only?

Answer 2

“a triplet of bases” in DNA

“codon” in mRNA only.

Question 3

What are the features of genes in terms of introns and exons in eukaryotic and prokaryotic genes?

Answer 3

Eukaryotic genes are (usually) discontinuous genes with coding exons and non-coding introns. Prokaryotic genes are (usually) continuous genes, lacking non-coding sequences.

Question 4

How can polypeptides be further modified?

Answer 4

Polypeptides can be further modified by the addition of carbohydrates, lipids or phosphate. Polypeptides can be combined as exemplified by haemoglobin.