Skip to content
Login Register

#DDT

3 public questions tagged with this topic.

Applied Ecology

Which synthetic compound class includes DDT?

DDT, or dichlorodiphenyltrichloroethane, is a synthetic chlorinated hydrocarbon insecticide. Its multiple carbon–chlorine bonds contribute to environmental persistence, and its hydrophobic character promotes accumulation in lipid-rich tissues. DDT and its metabolite DDE can biomagnify and impair reproduction in birds. Alkaloids are nitrogenous natural products, nitrosamines contain nitroso groups, and polyaromatic hydrocarbons are fused aromatic systems without this defining chlorination. Rates must be compared on the same area, biomass, leaf-area, and time basis because changing the denominator can reverse an apparent ecosystem ranking. Climate, nutrients, disturbance, species traits, and food-web structure interact, so broad ecological generalisations describe tendencies rather than universal rules. Energy is lost as metabolic heat at every trophic transfer, while elements such as nitrogen and phosphorus are recycled through organisms and the physical environment. Mechanistic interpretation connects individual physiology and species interactions to population change, community composition, and ecosystem-level fluxes. Reliable inference requires the complete experimental design, definitions, units, and statistical evidence; missing labels cannot be reconstructed from an answer key alone.

Ref: Campbell Biology, Urry et al., 12th Ed., Unit 8 Ecology

View Details
Applied Ecology

What effect did DDT have on birds?

DDT exposure caused eggshell thinning in many predatory birds through its metabolite DDE. DDE interferes with calcium metabolism and inhibits processes involved in shell deposition within the shell gland, so females lay fragile eggs that crack during incubation. Biomagnification made raptors and fish-eating birds particularly vulnerable. Population recovery after restrictions on DDT provided strong evidence linking the contaminant to reproductive failure. Energy is lost as metabolic heat at every trophic transfer, while elements such as nitrogen and phosphorus are recycled through organisms and the physical environment. Mechanistic interpretation connects individual physiology and species interactions to population change, community composition, and ecosystem-level fluxes. Reliable inference requires the complete experimental design, definitions, units, and statistical evidence; missing labels cannot be reconstructed from an answer key alone. Net primary production equals gross primary production minus plant respiration and represents biomass or energy made available for growth and consumers. Rates must be compared on the same area, biomass, leaf-area, and time basis because changing the denominator can reverse an apparent ecosystem ranking.

Ref: Campbell Biology, Urry et al., 12th Ed., Unit 8 Ecology

View Details
Applied Ecology

Which class of compounds includes PCBs and DDT?

Polychlorinated biphenyls and DDT are chlorinated hydrocarbons: organic molecules containing carbon frameworks with multiple chlorine substituents. Chlorination often increases chemical stability and lipid solubility, so these compounds resist degradation, partition into fatty tissues, and may biomagnify. PCBs were widely used in electrical equipment, whereas DDT was an insecticide. Neither compound is a carbohydrate, elemental heavy metal, or simply a generic plasticizer. Rates must be compared on the same area, biomass, leaf-area, and time basis because changing the denominator can reverse an apparent ecosystem ranking. Climate, nutrients, disturbance, species traits, and food-web structure interact, so broad ecological generalisations describe tendencies rather than universal rules. Energy is lost as metabolic heat at every trophic transfer, while elements such as nitrogen and phosphorus are recycled through organisms and the physical environment. Mechanistic interpretation connects individual physiology and species interactions to population change, community composition, and ecosystem-level fluxes. Reliable inference requires the complete experimental design, definitions, units, and statistical evidence; missing labels cannot be reconstructed from an answer key alone.

Ref: Campbell Biology, Urry et al., 12th Ed., Unit 8 Ecology

View Details