The Band Test. The back and front of your bra band should be level and parallel to the floor when you look at yourself from the side in a mirror. If the band is too tight, digs into your flesh or is just plain uncomfortable, it's too small.
Phagocytes are the white blood cells that protect the body by eating (phagocytosing) dirt, bacteria and dead or dying cells. They are important for fighting infections. They are also important for becoming immune. Phagocytes are important in all animals and are very complex in vertebrates.
The final function of the choanocytes is reproduction. The collar of the choanocyte is also able to capture incoming sperm for fertilization and help transport it to the egg cell within the sponge. In some species of sponges, specialized choanocytes can also transform into sperm cells, which are then released from one sponge to travel to another and fertilize it.