IB Biology SL A1.2 Nucleic Acids Questions

Practise IB Biology SL A1.2 with questions on nucleotide structure, DNA and RNA, complementary base pairing and genetic information.

Syllabus
First assessment 2025
Course
Biology SL
Level
SL

Exam points

  • draw a DNA nucleotide and connect phosphate, deoxyribose and base at the correct carbons
  • distinguish DNA from RNA using strand number, pentose sugar and thymine or uracil
  • deduce complementary bases or percentages and identify hydrogen or phosphodiester bonds

Question 1

[Maximum number: 1]

This redwood tree (Sequoia sempervirens) was blown over in 1936, but five side branches formed new roots and are now separate trees.

Three of the new trees formed from side branches of the original tree

Figure for Question 1 — IB Biology SL

State the molecule that trees such as redwoods use as genetic material.

Question 2

[Maximum number: 6]

Question (a)

(a)

The diagram below represents a DNA nucleotide.

Figure for Question (a) — IB Biology SL

Identify the phosphate group and deoxyribose.

Phosphate group:
Deoxyribose:

[ 1 ]

Question (b)

(b)

Draw a labelled diagram to show how four nucleotides are joined together to form a double-stranded DNA molecule with two base pairs.

Figure for Question (b) — IB Biology SL
[ 3 ]

Question (c)

(c)

State two differences between RNA and DNA nucleotides.

[ 2 ]

Question 3

[Maximum number: 2]

Outline the bonding between DNA nucleotides.

All question bank results loaded