IB DP Biology Mock Exam SL Paper 1B Set 3 - 2025 Syllabus
IB DP Biology Mock Exam SL Paper 1B Set 3
Prepare for the IB DP Biology Exam with our comprehensive IB DP Biology Exam Mock Exam SL Paper 1B Set 3. Test your knowledge and understanding of key concepts with challenging questions covering all essential topics. Identify areas for improvement and boost your confidence for the real exam
Question
(a) Identify which electron micrograph shows a mitochondrion, providing one observation to support your choice.
(b) Discuss the evidence for the theory that mitochondria may have evolved from free-living prokaryotes by endosymbiosis.
Answer/Explanation
Ans:
a) «micrograph» C cristae/double membrane is visible/«folds of» membranes inside
b)
a. «double» membrane may have formed when engulfed
b. replicate by binary fission like free-living prokaryotes
OR reproduce separate from «host» cell replication
c. they have their own «circular» DNA AND reproduce on their own
d. they have «70s» ribosomes AND can manufacture «their own» proteins e. have organelle«s» similar to free-living prokaryotes
f. similar in size to free-living prokaryotes
g. mitochondrial inner membranes manufacture ATP like bacterial membranes