The following passage describes the process of semi-conservative DNA replication, which is essential for the accurate inheritance of genetic material.
Complete the passage by writing a suitable word or words on each dotted line.
Before a cell divides, its entire genome must be copied. First, the enzyme ‾\underline{\hspace{3cm}} unwinds the double helix and breaks the hydrogen bonds between the polynucleotide strands.
Each of the separated parental strands serves as a ‾\underline{\hspace{3cm}} for the creation of a new strand.
Free DNA ‾\underline{\hspace{3cm}} align themselves alongside the exposed bases via complementary base pairing.
The enzyme ‾\underline{\hspace{3cm}} then catalyses the condensation reactions that join the nucleotides of the new strand together, forming phosphodiester bonds.
During this complementary pairing, the base cytosine always bonds with the base ‾\underline{\hspace{3cm}}.
As each new DNA molecule contains one original strand and one newly synthesised strand, the process is referred to as ‾\underline{\hspace{3cm}} replication.
66 exam-style questions on Edexcel IGCSE Biology Inheritance. Each one has a worked solution and a mark scheme showing where the marks go.