They need it to grow healthy
Here something that might help
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Most scientists believe that for half of </span>Earth's<span> 4.6-billion-year history, the</span>atmosphere<span> contained almost no </span>oxygen<span>. Cyanobacteria or blue-green algae became the first microbes to produce </span>oxygen<span> by photosynthesis, perhaps as long ago as 3.5 billion years ago and certainly by 2.7 billion years ago.</span>
Answer:
Gamtetes are sex cells, for humans, this manifests as the sperm cell and the egg cell.
Explanation:
Gametes are haploid cells unlike most of our body cells that are diploid cells.
Answer:
The correct answer will be option E.
Explanation:
The features given in the question are the characteristics features of the group of bacteria belonging to Cyanobacteria.
These Cyanobacteria are the prokaryotes which are capable of synthesizing the food through a process called photosynthesis. These bacteria use sunlight as their energy, use water and air to synthesize food. They under anaerobic condition synthesize the nitrogen in special structures called heterocyst, a characteristic feature of cyanobacteria.
Thus, the features given in the question are:
1. contain photosystems to carry out photosynthesis.
2. producing oxygen
4. contain phycobilins
6. Hetrocysts: nitrogen-fixing structures.
7. The ancestor of plant chloroplasts.
Thus, option E is the correct answer.
