Los glóbulos rojos son células que no pueden llevar a cabo la síntesis de proteínas pero contienen grandes cantidades de hemoglobina, la que se acumula en el eritoblasto, una fase temprana del desarrollo de los glóbulos rojos. De acuerdo a esto, ¿qué estructura debería presentar gran actividad en los eritoblastos?

i'd say that the moon rock is about 2.2 billion years old.

the oldest known insects are believed to live around 400 millions ago as suggested by the fossil records.   some plants having woody stems also evolved during this time.

after the evolution of insects the first four legged species or the tetrapods evolved in shallow freshwater habitats from the intermediate species approximately 397 million years ago. the tetrapods went on conquering the land giving rise to amphibians, reptiles, mammals and birds.

the major split in tetrapods first occurred 340 million years ago branching off from amphibians.

363 million years ago when the carboniferous period began the insects started roaming on land and taking flights, following which the four limbed tetrapods adapted in the terrestrial habitat.