Muscle tissue is a soft tissue that composes muscles in animal bodies, and gives rise to muscles' ability to contract. This is opposed to other components or tissues in muscle such as tendons or perimysium. It is formed during embryonic development through a process known as myogenesis.
Any light that exist was already emitted from somewhere. Any light that is absorbed, is destroyed, and is not emitted light; though, it may lead to light being emitted.
Answer: water, wind, volcanic rock, sand, and other stuff that can pile up basically.
