towards the head end

towards the tail end

towards the back side

towards the belly side

to stabilize the animal against rolling and to assist in sudden turns

provides the power to move a fish forward and acts like a rudder to help a fish steer

allows for up-and-down movement in the water and stabilizes a fish while swimming

allows for abrupt changes in side-to-side direction and speed. It also acts as a brake to decrease speed while swimming.

used for sperm transfer during copulation; reproduction

inject venom into predators

picks up the vibrations in the water, sensing changes in water current

to take in water and ventilate the gills; respiration

improves vision in low light conditions, allowing nocturnal and deep-water species to hunt effectively

provide protection from the environment and from predators

to kill and eat prey

take in odors from the environment

uninary papilla

food tube from the mouth to the stomach

to pump water over their gills even when they're not moving; respiratory/digestive functions

controls the passage of food and water from the esophagus into the stomach

secretes digestive enzymes that help in the breakdown of food in the intestine and also regulate blood glucose levels

stores and secretes bile

processing food

regulates the passage of partially digested food into the intestines

help in the churning and mixing the food with digestive juices

regulates the passage of partially digested food into the intestines

"U"-shaped portion of the small intestine that connects the stomach to the intestine

slows the transit rate of digesta through the gut and provides increased surface area for the absorption of nutrients

reabsorption of water and compaction of waste.

elimination of urinary and fecal wastes as well as an aperture through which the young "pups" are born.