In principle, the activated, GTP-bound form of Ras could be increased by activating a guanine nucleotide exchange factor (GEF) or by inactivating a GTPase-activating protein (GAP). Why do you suppose that Ras-mediated signaling pathways always increase Ras-GTP by activating a GEF rather than inactivating a GAP

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.

How do accessory pigments chlorophyll?

If a baby girl guinea pig looks almost identical to its mother, does this then mean that it inherited more alleles from its mother? explain. (hint: think about the vocabulary words dominant and recessive.)