It's the fin closest to the butt.
what do the dorsal and anal fins do for a fish
I guess you mean "Anal fin". If so, the answer is "yes fish do have an anal fin."
The anal fin is the one just in front of the fishes anus.
For stability
Behind the anal fin.
A female usually has a fan shaped anal fin( anal fin is on the bottom of the fish), and a male's anal fin is pointy, or "rod shaped".
The one closest to the bum.
Yes, it is the fin on the ventral surface of the fish between the anus and the caudal peduncle.
A fish has several different types of fins. There are the pectoral fins, located beneath the operculum (gills). There is the pelvic fin, located at the bottom of the fish, below the pectoral fin. There is the anal fin, which i located behind the anus, and there is the dorsal fin as well. It is located on top of the fish.
2 fins
The anal fin, is used to stabilize the fish while it is swimming.in some fishes such as trigger fishes.anal fin is used in sculling.in some live-bearinf fish,the anal fin of male is modified into a gonopodium.
The ventral fin on any fish is on the underbelly of the body closest to the anal vent.