Dentist specialties are recognized in those areas where advanced knowledge and skills are essential to maintain or restore oral health. The list of recognized dental specialties differs from country to country.
In contrast, radially symmetrical animals like jellyfish have a topside and a downside, but no identifiable front or back. The bilateria are a major group of animals, including the majority of phyla but not sponges, cnidarians, placozoans and ctenophores. For the most part, bilateral embryos are triploblastic, having three germ layers: endoderm, mesoderm, and ectoderm.
There are three types of symmetry in biology: Radial, bilateral, and asymmetry. Your son's teacher is most likely only concerned with the first two. Humans have bilateral symmetry. You can divide them into two equal parts.Starfish have radial symmetry.arthworms may appear to have radial symmetry because of their cylindrical shape, but DON'T BE FOOLED! They actually have BILATERAL symmetry. This is because they have an up and down (dorsal and ventral), and front and back (andterior and posterior). Linus Â· 9 years ago. Thumbs up.