EVERYDAY SCIENCE

Detailed explanation-1: -Placozoa (/plækəˈzoʊə/, “flat animals") is a phylum that consists of a diverse group of basal form of marine free-living (non-parasitic) multicellular organism called placozoans. They are the simplest in structure of all animals.

Detailed explanation-2: -To this day, Trichoplax remains the simplest animal known. It has no mouth, no stomach, no muscles, no blood and no veins. It has no front or back. It is nothing but a flat sheet of cells, thinner than paper.

Detailed explanation-3: -Placozoans are transparent, flat, round (up to 3 millimeters across), and have two distinct sides. A tissue layer composed of two types of cells, column-shaped cylinder cells with cilia and gland cells without cilia, make up the ventral (or bottom) surface.

Detailed explanation-4: -Placozoa occur in the littoral of all warm oceans and are distributed globally in tropical and sub-tropical waters [3-5]. They reproduce by (i) binary (sometimes trinary) fission, (ii) budding off small swarmers (iii) sexual reproduction [6-9].