The answer is (b.) male and female fish release their gametes together.
A cell's nucleus contains the DNA of the organism. The DNA is the same throughout the organism, but is expressed differently to create different cells (muscles, optic cells, bone, etc.)
Sorry for the delay, hope this helps :D
An involuntarily muscle contracts when you don't mean to do it, or you do it without thinking. One body function is the lungs contracting so you can breathe. you don't think about it it just happens. Hope this helped.
