The molecule that can MOST easily pass through the plasma membrane without assistance is carbon dioxide (CO2). Diffusion is a type of passive transport that occurs when molecules move in favor of a concentration gradient.
During diffusion, molecules move high concentration to a region of low concentration.
Oxygen (O2) and carbon dioxide (CO2) are non-polar gasses that move across cell membranes by a process called simple diffusion.
Simple diffusion is a type of passive transport that does not require energy to move substances across cell membranes.
I think it is true because musicians do have to know their instrments and they have to know how to play it how to read the music or if you sing there is a lot more to it. and with athletes they have to have good strength and they have to understand whatever sport they play.