One function is to attract pollinators
Nowadays, that theory is rejected. Friedrich Wohler was able to synthesize urea from cyanic acid and ammonium, both being inorganic matter. <---This disproves the theory of vitalism.
Answer
La corteza terrestre temprana apareció hace aproximadamente 4.500 millones de años, después de las últimas etapas de acreción planetaria.
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.
They are composed of actin, troponin, tropomyosin, and myosin
