Why is heartwood darker in color than sapwood?
a. heartwood is closer to the center of the stem; sapwood is away from the center of the stem
b. heartwood does not conduct water; sapwood is active in fluid transport
c. heartwood contains xylem tissue; sapwood contains phloem tissue

Agenetically engineered corn plant is approved for agricultural use. the plant produces pollen that can make its own toxins. these toxins protect the corn plant against pests and no longer require the application of chemical pesticide. what is a likely impact on the farmer of growing such a variety of corn? a- the financial costs for the farmer would be lowered since less crops would be lost to pests. b-the financial costs for the farmer would be lowered since more crops would be lost to pests. c-the farmer may be held responsible for increasing chemical pollution. d-the farmer's expenses for pest control would increase due to an increase in bee population.