This is the the biological process by which nitrogen (n2) in the atmosphere is converted into ammonia by certain prokaryotes.

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.

The most famous fossil called archaeopteryx is which of the following? a dinosaur a fern a fish a bird

What does the number 18.9984 represent in the image?