Answer:
Endoskeleton
Explanation:
An internal skeleton is called an endoskeleton, which is what vertebrates have. A sponge endoskeleton consists of short, sharp rods called spicules
Spicules are made of silica, calcium carbonate, etc.
Cellular respiration can be aerobic or anaerobic, but normally when people say cellular respiration they mean AEROBIC respiration. Aerobic means oxygen is needed while anaerobic means oxygen is not needed
Answer:
The definition of a pure line is a result of inbreeding where animals or plants have certain characteristics that are the same through generations. An example of a pure line is the result of inbreeding of a certain flower to help it fight off diseases.
It is not easily recognizable
it often supply energy and other nutrients and fiber that the body needs.