however some have more or less; in fact some starfish can have different numbers of arms even within one species. The mouth is located underneath the sea star on the oral or ventral surface, while the anus is located on the top of the animal....
(ventral, oral surface) surface of the animal, the anal and five (pentaradial) gonadal openings on the top (dorsal, aboral surface). Many sea stars (e.g.Asterias) are highly predatory and consume large numbers of animals even slower than they are e.g.molluscs. The main strategy in...
Joel looks up through the dorsal port but sees nothing. Several more impacts, staggered. The 'scaphe whirs implacably onward. 有东西从头顶冲过来;其撞击的沉闷湿响声在船体内短暂回响。Joel通过背部的观察窗向上看,但什么也没看到。接着是几次撞击,间隔有序。潜艇无情地继续前进。 "There." It looks ...
The gadiforms include the cods,haddocks, hakes, pollocks, and whitings, which are some of the world's most important commercial fishes. True cods (Gadinae) have three dorsal fins and two anal fins. Many species have chin barbels. The Burbot,Lota lota, of high-latitude, Northern Hemisphere...
the radial nerve cord, the common pyloric duct, which connects the pyloric region of the stomach to the paired pyloric caeca, and the extrinsic stomach retractor apparatus, which links the cardiac region of the stomach to the dorsal surface of the ambulacral body wall distal to the autotomy ...
Outbreaks of crown-of-thorns starfish are often attributed to step-changes in larval survivorship following anomalous increases in nutrients and food availability. However, larval growth and development is also influenced by the nutritional condition of