Question 1

Paper 2Easy4 marks

Figure 1 shows the number of possible DNA base sequences for strands of different lengths.

12340163248648096112128144160176192208224240256Length of DNA strand / nucleotide positionsNumber of possible base sequences41664256
(a)

Use Figure 1 to state the number of possible DNA base sequences for a strand of four nucleotide positions.

[1]
(b)

Use the pattern in Figure 1 to explain how a short DNA molecule can store a large amount of information.

[1]
(c)

Explain how complementary base pairing, based on hydrogen bonding, allows genetic information to be replicated and expressed.

[2]

More A1.2 Nucleic acids questions