Answer: the correct option is : highly developed cell- cell communication.
Explanation: In complex multicellular organisms, cell - cell communication also known as cell signalling is part of any communication process that leads basic activities of cells and coordinates multiple cell functions.
Valve created by soft palate keeps food out of nasal airway during swallowing
An atom consists of an atomic nucleus composed of positively charged protons and neutral or uncharged neutrons.
Explanation:
the name porifera means pore bearer in latin. a sponges body is covered by a skin, one cell thick. this skin has lots of small pores ad a few large openings. the small openings are the entrances to a complex system of channels. these collar cells pump water through the entire sponge and filter out food for the sponge cell to eat
