OCR A Level Biology A
OCR A Level Biology A Cellular Control Exam Questions
Free OCR A Level Biology A exam questions on Cellular Control, with mark schemes. Covers mutations, the lac operon, gene regulation, body plans and apoptosis.
Cellular Control exam questions
1 question pack of real past exam questions with its mark scheme. Answer every question without notes, then mark your answers line by line against the mark scheme.
StemUp mark scheme flashcards
OCR A Level Biology A H420 Flashcards (Anki & Quizlet)
Every answer is written in mark scheme wording, so you learn exactly what examiners give marks for. Use them on Anki or Quizlet, then test yourself with the questions on this page.
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About OCR A Level Biology A Cellular Control
This topic covers how genes are switched on and off.
What you need to know
- Mutations Substitutions, insertions and deletions and their effects.
- Lac operon Transcriptional regulation in bacteria.
- Gene regulation Transcription factors, post-transcriptional and post-translational control.
- Body plans Homeobox genes and apoptosis.
Common mistakes in Cellular Control
- Saying all mutations are harmful.
- Forgetting lactose binds the repressor.
- Confusing introns and exons.
Try three Cellular Control exam-style questions
1. Explain how a frameshift mutation affects a protein. (2 marks)
Show the mark scheme answer
Insertion or deletion shifts the reading frame (1), changing every codon after it (1).
2. Describe how the lac operon is switched on. (2 marks)
Show the mark scheme answer
Lactose binds the repressor (1), so it cannot bind the operator and RNA polymerase transcribes the genes (1).
3. State the role of homeobox genes. (1 mark)
Show the mark scheme answer
Control the development of the body plan.
Cellular Control FAQs
What does Cellular Control cover?
Mutations, gene regulation and body plans.
What is apoptosis?
Programmed cell death.
Why are homeobox genes similar across species?
They are highly conserved.
Revise this topic with flashcards: OCR A Level Biology A H420 Flashcards, with mark scheme answers for Anki and Quizlet.
