I believe it is a solution, sorry if wrong
<span>The part of the ear where sound wave compressions and
rarefactions cause the eardrum to vibrate is the middle ear. The 8th
nerve in the inner ear actually converts the mechanical energy to electrical
energy for transmitting to the brain. A membrane called the tympanic membrane
separates the middle ear from the outer ear. Whenever a sound reaches the ear,
it creates a sound wave that creates vibration in the eardrum. The pressure
when high pushes the membrane inwards while low pressure sound waves helps the
eardrum to come outwards. </span>
The structure is a phospholipid bilayer. There are many phospholipids which contain a water loving phosphate end and a water hating lipid (fatty) end. The phosphate ends all point out words while the fatty ends are inside.
The purpose is protection of the cell as well as allowing certain molecules to enter and exit the cell
A holdfast is a root-like structure that anchors aquatic sessile organisms, such as seaweed, other sessile algae, stalked crinoids, benthic cnidarians, and sponges, to the substrate.
