Responder: en qué nivel de organización situarían a: una molécula de ADN,
una bacteria, un hígado, un cloroplasto, un trozo de hierro, un grupo de
palomas, un pez, un río con peces y algas, un pulmón. ¿cuál de estos niveles
tiene vida?

small, big, or no change could occur in the phenotype. it could cause something as simple as a cats ears to curl backwards or something as frighting as death. it could also occur in the protien-coding area and have an effect on that but no effect on the amino acids. what has to occur is a changing in the hox gene or the control gene.

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link:

oxygen = 21% of the atmosphere

nitrogen = 78%

carbon dioxide = 0.1%

argon =0.934%