Transgenic agriculture is the use of genetically modified crops to

Transgenic agriculture is the use of genetically modified crops to enhance the production of food and other farm products. Genes from another species are added to a crop to introduce new traits, such as resistance to herbicides, that are not present in the original. One widespread application involves the addition of genes from Bacillus thuringiensis, a soil bacterium that produces insecticidal toxins, to corn, producing a hybrid that is resistant to insect pests.

Proponents of this agricultural biotechnology argue that it has enormous potential benefits. The corn hybrids produce delta endotoxins, which are generally thought to be harmless to humans and other nonpest species, but toxic to certain insect pests. Production of the insecticide within the plant reduces crop losses from the pests and also reduces the need for application of conventional insecticides and other agrochemicals, which can harm humans and cause other environmental damage.

Traditional insecticide treatments involve spraying of the delta endotoxins on the vulnerable crops. However, the chemicals break down rapidly when exposed to ultraviolet light, a problem avoided when the toxins are produced internally to the plant.

The growth of genetically modified crops has sparked opposition on a number of counts. The toxins produced in the plant remain in the soil when the crop is plowed under, accumulating over time with unknown effects at high levels of concentration. The insecticide has the potential to spread upwards through the food chain, starting with predators that consume contaminated insects and, in turn, become prey for other species. Transgenes can spread to nearby wild plants through crop-weed hybridization, a process that is extremely difficult to control, transmitting superior traits to unintended recipients. Fears of these “superweeds” motivate a number of the opponents of genetic modification. Finally, transgenic agriculture encourages monocultures, genetically homogeneous fields, which are ironically more vulnerable to pests and disease because they lack the genetic diversity that provides the natural defense of evolution.

1. According to the passage, delta endotoxins

A. are added to a crop, such as corn, to introduce new traits found in another species
B. are one of several types of herbicide
C. are generally perceived to be harmful to humans
D. decompose quickly under certain forms of radiation
E. can spread to nearby plants through crop-weed hybridization

2. With which of the following statements would the author of the passage be most likely to agree?

A. The dangers of transgenic agriculture outweigh any possible benefits.
B. Genetic modification can create crops that are particularly vulnerable to the very dangers it was trying to reduce.
C. Traditional insecticide treatment carries less risk to other species than does transgenically produced insecticide.
D. Proponents of transgenic agriculture cite the creation of “superweeds” as evidence of the technology’s potential benefits.
E. Plants that are contaminated with delta endotoxins shouldbe plowed under the soil.