It is called a sister chromatid, not a polar body.
Medulla oblongata is the part of the brainstem that controls the autonomic functions such as sneezing, coughing, digestion and etc.
Invertebrate doesn't posses "Backbone" whereas Vertebrate chordate have that. That's the only & most important difference between them.
Hope this helps!
Answer:
It processes undigested food into feces.
Explanation:
