Which organism is likely to accumulate the highest level of DDT in its body?
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Answer: C. Sea gull
Explanation
Top apex predators in marine food webs, such as sea gulls, experience high levels of biomagnification, accumulating the greatest concentrations of DDT. Persistent organic pollutants multiply in concentration at each ascending trophic level in aquatic food chains. Seagulls feed on contaminated fish near the top of the food web, concentrating toxins in their fatty tissues. Biomagnification is the process where fat-soluble toxins increase in concentration in living tissues at higher trophic levels. DDT resists metabolic breakdown, causing it to persist and accumulate persistently within animal fatty tissues. Phytoplankton absorb trace amounts of DDT from water, initiating the trophic bioaccumulation process.
Option A refers to eels, which occupy lower trophic positions than top marine predatory birds like sea gulls. Option B lists crabs, which accumulate toxins but generally experience lower biomagnification than apex aerial predators. Option D lists phytoplanktons, which sit at the base of the food web and contain the lowest baseline toxin levels.
- Subject
- Agriculture
- Category
- Forestry
- Topic
- —
- Difficulty
- medium
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