Mecanismo para bombear ciertas sales disueltas fuera de la célula, en contra de su gradiente de concentración A. osmosis C. transporte activo
B. difusión D. difusión facilitada

What type of competition exsist between two species. turtles and fish

Which process of living things produces water that enters the water cycle

According to theories of how life began, how did early organic molecules begin to separate from the outside world? a: specialized enzymes were required b: chains of amino acids created a barrier c: formation of microspheres or vesicles d: rna catalyzed the formation of membranes