Answer:
La química es la ciencia que estudia la composición, estructura y propiedades de la materia, así como los cambios que esta experimenta durante las reacciones químicas y su relación con la energía.
Explanation:
Answer:
"pumps blood against a greater resistance" that the answers. hope this helped
The Cỉculatory system is an organ system that permits blood to everywhere in the body and transport nutrients, oxygen, carbon dioxide, ...to help fighting diseases ,.... The main parts of the Circulatory system are heart , lungs , veins , vessels, arteries,...
Answer:
Due to presence at early days of the planet.
Explanation:
We only find the remains of single celled organisms in the oldest fossils because the single celled organisms are the organisms that were present in the early days of this planet. These single celled microbes were present about 3.7 billion years ago while on the other hand, the oldest rocks are only a little older i. e. 3.8 billion years so these single celled organisms are considered as oldest fossils on this planet.
