What term describes the ability of an animal to know the meaning of the signals it sends and receives?

cognition

instinct

behavior

communication

From higher to lower the two layers that plants make up in a tropical rain forest are the

Let's see how much you picked up from analyzing the digital timelines. Why do historians use chronology as an organizing principle?

Extensive irrigation in arid regions causes salts to accumulate in the soil. (When water evaporates, salts that were dissolved in the water are left behind in the soil.

How can the fossil record provide evidence for evolutionary relationships?

How many copies of DNA does meiosis start with?

Excluding skin cancer, the most common cancer in american males today is

Describe the usefulness of the hardy-weinberg model to population geneticists

Is potassium an element

Why is there controversy to the opinion that human contribution of carbon dioxide to the atmosphere is causing global warming? choose the answers that best fit Because the Earth goes through periodic cycles of cooling and warming.

Which is not true of lipids? They form structural parts of cell membranes. They supply cells with nitrogen. The carry fat-soluble vitamins to cells. They supply cells with energy.