How can biomagnification of substances like mercury or PCBs impact human health?

• A. It increases the rate of photosynthesis in human cells.
• B. It reduces the risk of infectious diseases in human populations.
• C. It can lead to the accumulation of toxic substances in human tissues, causing neurological and developmental problems.
• D. It enhances the absorption of essential nutrients in the human digestive system.

Answer: (C)

Verified step by step guidance

1. Understand the concept of biomagnification: Biomagnification refers to the process by which the concentration of toxic substances, such as mercury or PCBs (polychlorinated biphenyls), increases as they move up the food chain. These substances are not easily broken down and tend to accumulate in the tissues of organisms.
2. Recognize the role of trophic levels: As smaller organisms (e.g., plankton) absorb these toxic substances, they are consumed by larger organisms (e.g., fish). At each trophic level, the concentration of the toxic substance increases because the predator consumes multiple prey, each containing the substance.
3. Connect biomagnification to human health: Humans, as apex predators, often consume organisms at the top of the food chain (e.g., large fish like tuna or swordfish). This leads to the accumulation of high concentrations of toxic substances in human tissues.
4. Identify the health impacts: Substances like mercury and PCBs are known to cause neurological and developmental problems in humans. Mercury, for example, can interfere with brain function, while PCBs can disrupt hormonal systems and lead to developmental issues.
5. Eliminate incorrect options: The other options provided (e.g., increasing photosynthesis, reducing infectious diseases, or enhancing nutrient absorption) are unrelated to the process of biomagnification. The correct answer is that biomagnification can lead to the accumulation of toxic substances in human tissues, causing health problems.