I believe that both flatworms and roundworms have a body type called Bilateral symmetry. Animals that are bilaterally symmetric have mirror symmetry in the sagittal plane, which divides the body vertically into left and right halves, with one of each sense organ and limb pair on either side.
The membrane is selectively permeable because substances do not cross it indiscriminately. Some molecules, such as hydrocarbons and oxygen can cross the membrane. Many large molecules (such as glucose and other sugars) cannot. Water can pass through between the lipids.
ER, golgi, or mitochondria ♀️
It is an advantage due to the fact you do not have to think about it. therefore while sleeping you still breathe and you do not have to be conscious
