I think the answer is "the older it is"
Reason: I might be wrong but is something (like a shell) gets buried in something (like sand), overtime many things (like dirt, soil, sand, etc.) will be on top of the original. This will make layers. So, the older rock is on the bottom since it has been there for the longest and it gets covered by other stuff (causing the layers).
Hope this helps! :) (If I'm wrong, sorry :( )
Sunlight is the original source of almost all energy in most ecosystem.
Protein synthesis as well as DNA transcription
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.
