Which use pedicellariae to keep the body surface free of debris?

Which layer will become saturated first when rain falls?

Idon’t know the answer and i’ve been stuck on it for a while now skskskskks

According to theories of how life began, how did early organic molecules begin to separate from the outside world? a: specialized enzymes were required b: chains of amino acids created a barrier c: formation of microspheres or vesicles d: rna catalyzed the formation of membranes