Zoology 10th Edition by Stephen Miller,John Harley

تمرين 10

Which of the following statements about annelids is true?
A) They have an open circulatory system.
B) Their dorsal nerve cord begins anteriorly at suprapharyngeal ganglia.
C) Most gas exchange occurs as a result of diffusion of gases across the body wall and parapodia. Some annelids have parapodial gills.
D) Most adult annelids use protonephridia in excretion.