Yes, they do.
Simple nothing
Yes, perch, like all fish, have a heart. Their heart is a muscular organ that pumps blood through a single circulatory system, delivering oxygen and nutrients to their body while removing waste products. The heart of a perch typically has two chambers: an atrium and a ventricle, which help circulate blood efficiently throughout their bodies.
muscular and skeletal
The Muscular-Skeletal System.
The nervous system.
the muscular and cardiovascular system.
the main organ of the muscular system is the muscles
The nervous system tells the muscular system what to do.
muscular system
nothing
Gills
Your bones are part of your skeletal system, not muscular.