Cephalization is the differentiation of end part of the body into a head in which nerve tissue is concentrated. Sponges have a very loose nervous system and their cells work individually, not controlled by a nervous system. Since they have no defined head as a consequence of concentrated nervous system, the sponges could not have cephalization either.
The skin acts as a barrier for protecting the body from the harmful things such as sun rays, moisture, cold.
<u>Explanation:</u>
Skin plays an important role in regulating body temperature. It helps to prevent harmful substances enter into our body, and does not allow to loss water in our body. Its form the barrier that prevents harmful substances and microorganisms enter in our body.
Our skin is the protecting layers and against loss of water and blood from our body. Its help us to maintain the constant body temperature. The important role of the skin us to protect our body from the ultraviolet rays.
Most peripheral nerves are nerves outside the brain and the spinal cord, carrying both sensory and motor impulses. The peripheral nervous system is one of the two components of the nervous system, the other part is the central nervous system. Peripheral nerves are classified into motor, sensory and autonomic nerves.
OBSERVATIONAL LEARNING is associated with the fearless peer experiment. The experiment demonstrates OBSERVING OTHERS AND POSITIVE BEHAVIORS.
Fearless peer experiment is about a video show about a small boy who was having fun playing with dogs. What was seen inside the video encourages the watchers to lose the fear they have for strange dogs.