Using the gas pedal analogy, the proto-oncogene would be an accelerator since they promote cell division and
deregulate apoptosis, while tumor suppressor would
be the brakes since they constrain the progress of the cell
cycle and induce cell apoptosis. An
oncogene is, therefore, when the accelerator
is stuck in down position and the brakes are not working.
D, the black squirrels have survived because black has provided them with an advantage in this environment.
The CORRECT answer for this is: number reduction of chromosomes:)
DNA testing and if they have certain strands that we dont
Pollen tube growth is one of the most fascinating—and essential—phenomena in the life cycle of flowering plants. After a compatible interaction between pollen grains and the stigma surface, the pollen germinates and forms the pollen tube, which grows through the stigma, style, and transmitting tract to deliver the sperm cells to the ovule."
2) Although pollens of many species germinate in simple aqueous media, stigmas do not provide satisfactory sites for the germination of most foreign pollen... Stigmas not only provide the proper conditions for the germination of pollen from their particular species, they actively inhibit the germination of pollen of many unrelated species.