Before an ozone layer formed to reduce radiation, life existed
a. in the air.
c. in oceans and underground.
b. in trees and plants.
d. on land.

List the advantages and disadavantages of the switch from persistent chlorinated hydrocarbon pesticides (such as ddt) to nonpersistent organophosphate pesicides. have the benefits of the switch outweighed the disadvantages? explain.

Awire-hair terrier and a smooth-hair terrier are mated. the offspring produced are 6 wire-hair puppies and 2 smooth-hair puppies. a. what pattern of inheritance best describes this situation? b. what is the genotype(s) of the wire-haired puppies? of the smooth-haired puppies? c. what would be the expected genotype and phenotype ratios of a mating between 2 wire-haired terriers that are heterozygous?

How would you describe the the organisms in the second row of model 1 that are connected to the parents by a line