The one that helps identify leaves as monocot or dicot are the characteristic of their veins. In a monocot, leaves have parallel veins or parallel venation; whereas, dicot leaves have a network of veins or reticulate venation. Hope this is the answer that you are looking for. Have a great day!
Answer:
In Branchiostoma, it is used mainly for feeding. The pharynx consists of numerous pharyngeal bars, with pharyngeal slits between them. The animal sucks in water through its mouth and forces it out through the pharyngeal slits, capturing small food particles from the water