proto

Siphon

...r, it is said to have a siphon o stele . See also proto stele and eu stele . sister group -- The two clade s resulting from the splitting of a single lineage . Full article >>> Siphon ophora - the "conveyor belt" of the upgrowing larva e and the ovarium can be seen Plankton are also of...

Protozoa

Protozoa (in Greek proto = first and zoa = animal ) are single-celled eukaryotes ( organ isms whose cells have nuclei) that show some character istics usually associated with animals , most notably mobility and heterotroph y. Full article >>> Protozoa...

Protista

... or colon ial. proto-oncogene . See oncogene . proto chordates Chordates that lack a backbone. Full article >>> Radiolaria. Protista n phylum , whose members are planktonic and secrete an often elaborate siliceous test Radula. A belt of teeth, found in gastropods and chitons. Used f...

Olfactory bulb

...be divided into four parts, the optical lobes, the proto cerebrum , the deuto cerebrum , and the trito cerebrum . Full article >>> The axons from all the thousands of cells express ing the same odor receptor converge in the olfactory bulb . Full article >>> A tuft of ca...

Medulla oblongata

...be divided into four parts, the optical lobes, the proto cerebrum , the deuto cerebrum , and the trito cerebrum . The optical lobes are positioned behind each eye and process visual stimuli (Butler, 2000). Full article >>> inner portion of an organ such as the medulla of a kidney ; med...

Chordate

... cord, gill slits, and a notochord . Includes the proto chordate s and the vertebrates . Full article >>> hh genes have been identified in several other invertebrate species including the leech and sea urchin (Chang et al.1994) as well as in the cephalo chordate amphioxus (Shimeld 199...

Chordates

... cord, gill slits, and a notochord . Includes the proto chordates and the vertebrates . Full article >>> proto chordates . It also has a well- character ized allorecognition system called Fu/HC whose functions...

Cerebrum

...ystem , the brain is anatomically divided into the proto cerebrum , deuto cerebrum , and trito cerebrum . Immediately behind the brain is the subesophageal ganglion which controls the mouth parts. Full article >>> Region of the brain that acts as a relay station between the cerebellum and...