They form a complex called chromatin
Answer:
lactose, repressor, RNA polymerase (or mRNA might fit here), transcription, repressor, RNA polymerase
Explanation:
Hope this will help.
Answer: Adaption (I think)
Explanation: Certain living organisms and animals can adapt to harsh environmental conditions, and if I'm not wrong, cells can adapt, as well.
Answer:

✏ Arteries are the vessels that carry blood away from the heart to various organs of the body.Since, the blood emerges from the heart under high pressure, the arteries have thick, elastic walls.