Which material is an aquifer layer most likely made of? soil
clay
solid granite
cracked rocks

Which of the following describes a difference when gram-positive bacteria are compared to gram-negative bacteria?

In general, characteristics that an organism survive and reproduce become more common over time. what mechanism of evolution causes this?

The graph shows the amount of global warming happening in different ecosystems. which populations of organisms will likely decline the most as a result of climate change, and why? a.coral reefs because of the loss of the symbiotic algae living within their bodies b.penguin populations because the fish they eat will move into warmer waters c.mountain-dwelling birds because rising sea levels will relocate their food sources d.large cats in the rainforest because of decreased habitat loss for their prey