IB Biology HL D2.2 Gene expression questions

Exam-style multiple choice and written questions with full markschemes. Check multiple choice answers straight away, or type, photograph or draw a written answer and get it marked.

Type
Multiple choiceWritten
Difficulty
EasyMediumHard

Question 1

Multiple choiceEasy1 mark

In a cell, cytosines in the promoter of gene P are methylated, while amino acids in histones in nucleosomes associated with gene H are methylated. Which interpretation of transcription is consistent with these tags?

Show answer and explanation

Answer: C. Cytosine methylation in a promoter represses transcription of the downstream gene. In contrast, methylation of histone amino acids in nucleosomes can either repress or activate transcription. A: Extends the two possible effects of histone methylation to promoter cytosine methylation. B: Reverses the effect of promoter cytosine methylation, although its histone statement is correct. D: Treats histone methylation as invariably repressive, excluding its possible activating effect. Remember: the effect of methylation depends on whether the tag is on promoter DNA or histones.

The best questions are still waiting

Unlock every question in this topic, then type, photograph or draw your answer and have it marked against the markscheme. Find out where you are dropping marks.

Unlock all questionsCompare Student and Student Plus