Structural Systems
The structural system of an animal is made of bones, quite commonly. It also may be made of cartilage, the material in the human ear. For example, sharks have a structural system made of cartilage rather than bone. Birds have bones, but they are hollow to allow the birds to fly. For the most part, the structure of an animal is the same, using
Plants often have a vascular base, allowing the plant to hold against gravity. Bryophytes have no vascular base, and are quite short due to the lack of vascular qualities. Vascular plants, such as anthophytes, are capable of holding a great amount of weight on the stem of the plant; enough structure to hold up a heavy flower or fruit, even.