Answer:
The answer is letter B
Explanation:
A cell contains thousands of different kinds of enzymes, each promoting a different chemical reaction.
D. Lymph nodes are the filtering points throughout the body... found in the lymphatic system
One result of a loss of ground water would be that the freshwater on earth is 98 percent stored in the ground, therefore we would lose 98 percent of the very little amounts of freshwater we have
<u>Answer:</u>
Cyanobacteria start producing pure oxygen around 200 million years ago.
<u>Explanation:</u>
Many scientists believed that Earth did not have any oxygen. Cyanobacteria or the blue green algae are the microbes which produced oxygen for the first time with the help of photosynthesis. This was around 4.5 billion years ago: after Hadean eon.
They were very simple, but they produced oxygen in the early earth’s atmosphere. So, they brought evolution on earth. This “blue-green algae” exists in salt water, rocks and soils and play a major role in maintaining the ecosystem.