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.
Both plant and animal cells have a mitochondria! Plant cells have a cell wall, a cell membrane and a chloroplast. Animal cells have a lysosome, where as plant cells usually don't have this present.
Answer:
is d. The bacteria have high genetic variability and high reproductive rates.
Explanation:
