National 5 Biology practice questions

Original questions for every key area, with worked explanations.

Multiple choice	Section 1 style, worked or timed
Section 2	Structured and extended-response questions
Experiments	Variables, results and improvements
Written answers	Read against the mark points, with your next step

Try 4 questions

Question 1

The graph shows the rate at which catalase from celery released oxygen at different temperatures. What is the optimum temperature for this catalase?

Question 2

Which structures make up the central nervous system (CNS)?

Question 3

The diagram shows a section through a leaf. Which row names the structures labelled X and Y?

Question 4

Which statement about mutations is correct?

Are older past papers still useful?

Yes, for practice. Since 2027 the paper is 80 marks in 2 hours, so time yourself to the new length.