I think the first option is the answer.
What are you trying to ask?
Answer: Ligand gated channel
Explanation:
Ligand gated channel is an essential membrane protein that has pores and allows the passage of specific ions across the plasma membrane when it is activated by a specific chemical . Examples of such ions that pass through Ligand gated channels are Sodium ions, Potassium ions, Calcium ions. Ligand gated channels are found in extensions of the nerve cells.
DNA and RNA have completely different purposes in us. DNA stores and transfers genetic information (Eye and hair colour, skin colour, etc..). RNA codes amino acids and makes proteins. DNA is double stranded while RNA is single stranded. DNA uses adenine, thymine, cytosine, and guanine; while RNA uses adenine, cytosine, uracil, and guanine.