Answer:
A vertebrate is an animal with a spinal cord surrounded by cartilage or bone. The word comes from vertebrae, the bones that make up the spine. Animals that are not vertebrates are called invertebrates. Vertebrates are adapted to life underground, on the surface, and in the air. They feed upon plants, invertebrate animals, and one another. Vertebrate faunas are important to humans for food and recreation.Vertebrate Classes
Agnatha (Jawless Fish) Aves (Birds) Amphibia (Amphibians) Chondrichthyes (Rays, Sharks, Skates) Mammalia (Mammals) Osteichthyes (Bony Fish) Reptilia (Reptiles)
Explanation:
Is that a test your taking?
i think that is is gravity becasue gravity pulls the planets
B. outer covering
b. it preforms all functions
Just as the organs in an organ system work together to accomplish their task, so the different organ systems also cooperate to keep the body running. For example, the respiratory system and the circulatory system work closely together to deliver oxygen to cells and to get rid of the carbon dioxide the cells produce.