Gas retailers, though, grouse that Costco uses gas as a loss leader to get people into the store. Even though Costco has just 0.16% of the 170,000 places you can fill up your car in the United States, its model is roiling the industry.
The release of fish eggs and their subsequent fertilization is called spawning. Most marine fish reproduce by releasing thousands of small eggs into the water for external fertilization. Egg-laying fish have a variety of methods for releasing the eggs. Some fish scatter eggs, which are fertilized by the male fish as they fall. Other fish attach the eggs to a surface, where they are then fertilized as they are released. Some fish release eggs into a nest of bubbles blown by the male fish.
Characteristics of the Five Vertebrate Groups. Fish. The body of the fish is covered in scales and has fins attached to help it move through the water. Fish breathe using gills which take oxygen out of the water.When male and female fish mate, the eggs often meet the sperm in the water.This is called external fertilization. Examples of fish are the herring, which lives in the sea, and the pike which is a freshwater fish.Amphibians. The skin of amphibians is very thin and must always be kept wet because amphibians breathe through their skin.his is called external fertilization. Examples of fish are the herring, which lives in the sea, and the pike which is a freshwater fish. Amphibians. The skin of amphibians is very thin and must always be kept wet because amphibians breathe through their skin.