The answer is A. They do not sweep food. They are used for transportation
Oxygen is the answer for this question.
Answer:
The secondary structure of a protein is held by, hydrogen bonds between the carboxyl groups and the amino groups in the polypeptide backbone.
Answer:
The answer is letter a, chemical evolution.
Explanation:
Chemical Evolution <u>is one of the processes that helps explain the origin of life. It states that the first living cell on earth started from non-living matters that were not capable of reproducing.</u>
This <em>non-living matter </em>could be both <em>organic and inorganic molecules.</em> It is said that the structures of these molecules changed over time (example is protein breaking down when exposed to too much heat). When these systems become complex, they form new structures (this is known as repetitive reproduction). This then gives rise to bacteria.
Thus, this explains the answer.