Answer:
Most biomolecules are organic compounds, and just four elements, oxygen, carbon, hydrogen, and nitrogen make up 96% of the human body's mass. But many other elements, such as the various biometals, are also present in small amounts.
Answer: C) a factor that may affect an experiment or investigation
Explanation:
This is the best answer. A and B can be eliminated. D describes a controlled variable which is more specific than a scientific variable, thus C is the best answer. It is the best description of just a scientific variable.
A catalyst decreases the activation energy and increases reaction rate that is needed.
Do you mean when nucleotides get damaged or when they match to each other incoreectly? (which cuases mutants) Specialized Enzymes repair, different one respond to help different types of damage. Detail the question more, maybe then i can help more.
They are related because they are all in the same blood or family you breathe in oxygen and remove carbon dioxide the carbon dioxide it helps other stuff in the ecosystem to survive or live so its like this people breathe oxygen while plants breathe carbon dioxide.