Do you see a pattern relating survival of wildtype bacteria vs “sunscreen” bacteria?
The correct answer and explanation is:
Correct Answer:
Yes, there is a pattern. The “sunscreen” bacteria tend to have higher survival rates than the wildtype bacteria when both are exposed to ultraviolet (UV) light.
Explanation:
When comparing wildtype bacteria to genetically modified “sunscreen” bacteria under UV exposure, a noticeable survival pattern emerges. The wildtype bacteria generally show lower survival rates because they lack enhanced protective mechanisms. UV light damages bacterial DNA, causing mutations or cell death. Without additional protection, wildtype strains suffer more from this damage, leading to reduced colony growth or complete cell death.
In contrast, “sunscreen” bacteria are typically engineered or selected to produce pigments or proteins that absorb or block harmful UV radiation. These substances act like a biological sunscreen, shielding the bacterial DNA from direct UV damage. For example, some bacteria produce melanin or carotenoid pigments, which absorb UV light before it can damage cellular components. As a result, the sunscreen bacteria maintain higher viability and show increased growth compared to wildtype strains under the same conditions.
This pattern is often confirmed through laboratory experiments. When both types of bacteria are spread on agar plates and exposed to UV light for a fixed period, fewer colonies appear for the wildtype, while the sunscreen bacteria show relatively dense growth. This indicates better survival and resilience.
This difference highlights the importance of protective adaptations in harsh environments. In nature, bacteria exposed to strong sunlight might evolve protective pigments over generations. In a lab, these traits can be artificially introduced to study their effects. The pattern consistently shows that UV protection correlates with improved survival. This knowledge is useful in microbiology, genetic engineering, and even in the development of new sunscreens or biofilms that protect surfaces from UV radiation.