In rats, the genes B and D control fur color as follows: B_dd rats have black fur, bbD_ have yellow fur, B_D_ have brown fur, and bbdd rats have cream-colored fur. If a pure-breeding brown rat and a pure-breeding cream-colored rat mate to produce an F1, and F1 are allowed to interbreed to produce an F2, what is the expected phenotypic distribution of the brown fur color rat offspring

Acladogram is a branching diagram that represents suggested evolutionary relationships among organisms based on the presence of unique traits. a scientist discovers a new organism that lacks limbs and does not have a true backbone. the organism lays eggs to produce offspring and has a cartilage-like rod known as a notochord running along its dorsal surface. on the cladogram below, select the species to which the newly discovered organism is most closely related.

Recent research by marine biologists suggests that bottlenose dolphins have names for themselves. scientists played sounds they had identified as the names of particular dolphins, putting them through a synthesizer so that they did not sound like the voices of particular dolphins. the researchers found that dolphins would respond to the names of other dolphins that they were related to or associated with, but they ignored the names of strangers. this discovery suggests a much greater degree of self-awareness in aquatic mammals than was previously suspected. if this research holds up, what does it suggest about dolphins?

Each pair of clay balls represents two planetesimals. if each planetesimal is composed of the same material and is separated he the same distance, which pair experiences the frayed gravitational attraction?