IB DP Biology Mock Exam SL Paper 1B Set 1 - 2025 Syllabus
IB DP Biology Mock Exam SL Paper 1B Set 1
Prepare for the IB DP Biology Exam with our comprehensive IB DP Biology Exam Mock Exam SL Paper 1B Set 1. 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
| Organism | Scientific Name | Genome Size (million base pairs) |
|---|---|---|
| Nematode worm | Caenorhabditis elegans | 100 |
| Thale cress plant | Arabidopsis thaliana | 160 |
| Fruit fly | Drosophila melanogaster | 180 |
| Tiger pufferfish | Takifugu rubripes | 400 |
| Rice plant | Oryza sativa | 490 |
▶️ Answer/Explanation
(a)
The total genome size is 100 million base pairs.
If there are 64 million A–T base pairs, then the remaining base pairs must be C–G pairs.
Calculation: 100 mbp – 64 mbp = 36 mbp.
Therefore, the number of cytosine–guanine base pairs is 36 million.
\(\boxed{36 \text{ million}}\)
(b)
Base pairs are found in DNA, which is located within specific organelles. One such organelle is the nucleus.
Other acceptable answers include mitochondria or chloroplasts (in plants).
\(\boxed{\text{Nucleus}}\)
(c)
Current and potential future uses of whole genome sequencing include:
- The increasing speed and decreasing cost of sequencing make it practical for determining the genome of any species.
- It allows for the determination of evolutionary relationships and common ancestry, providing evidence for evolution and aiding in species classification.
- It facilitates biodiversity conservation efforts and can help in restoring endangered or extinct species.
- It enables the development of personalized medicine, where treatments can be tailored to an individual patient’s genetic profile.