Sickle cell anemia is caused by a single letter mutation so transcription will lead to synthesis of a different <u><em>mRNA</em></u> molecule . The different mRNA molecule will lead to a different <em><u>protein</u></em> where a single amio acid is different(there is valine instead of glutamic acid)
If a substance is not able to be separated by physical means but is able to be separated by chemical means, it is a compound.
Salutations!
<span>Cells that perform similar functions combine to form: ----
</span><span>Cells that perform similar functions combine to form: tissues. A group of tissues working together combine to form an organ system. Organs working together combine to form an organ system. Organ system performing their functions makes an organism.
Thus, your answer is option D.
Hope I helped (:
Have a great day!</span>
Answer:
Speeding up chemical reactions by lowering the activation energy.
Explanation: