Answer:
A, the sun.
Explanation:
The sun powers the water cycle and many others.
Answer:
Stephen Stearns states that natural selection doesn't mean the survival of the fittest organisms, but rather this mechanism is illustrated by the selective reproduction of the fittest. Natural selection can be classified into distinct types, including directional, disruptive and stabilizing selection, which are in turn based on sexual selection. These types of selection are driven by different outcomes that have different dynamics.
Answer:
la mutación es un cambio en el modo genético. El tipo físico de adaptación es un cambio en una parte del cuerpo y el tipo de comportamiento es una respuesta animal a un estímulo externo.
Espero que esto ayude
Answer:
The return of blood to the heart is assisted by the action of the skeletal- muscle pump. As muscles move, they squeeze the veins running through them. Veins contain a series of one-way valves, and they are squeezed, blood is pushed through the valves, which then close to prevent backflow.
