Name of the german scientist from the 1800's that studied animals

Aresearcher has developed two stains for use with seed plants. one stains sporophyte tissue blue; the other stains gametophyte tissue red. if the researcher exposes pollen grains to both stains, and then rinses away the excess stain, what should occur? a) the pollen grains will be pure red. b) the pollen grains will be pure blue. c) the pollen grains will have red interiors and blue exteriors. d) the pollen grains will have blue interiors and red exteriors.

Apopulation of black bears depends on salmon from a stream for food. if a drought causes the stream to run dry one year, how will this likely impact the black bear population?

Any sound above what db can cause hearing loss in human beings