Answer: A, restriction endonuclease
Explanation: None just know it
Carbon dioxide not being able to leave the lungs
I'd think that'd be the Myelin Sheath
Answer: B. They are located and bind the steroids in the cytoplasm
Explanation: Steroid hormones are a class of organic compounds, typically lipids. They bind to protein receptors in the cytoplasm or nucleus of the target cell and thus, their receptors are located inside target cells where they function as ligand-dependent transcription factors. This is to say that hormone-receptor complex formed on binding to DNA activates specific genes that increases production of proteins.
