A crystals shape is determined by the arrangement of the atoms or molecules inside the crystal.
I would say its C but im not for sure
B. the activity keeps blood levels of ammonia within a certain low range that the body can tolerate
Refraction- bending of light waves (ex. straw in a cup of water looks bent on a side but really is NOT, this is due to refraction, it bends the light waves reflected)
Luminescence- Creation/Emission/Starting or making of light through ways that DO NOT INVOLVE heat.
Ultraviolet- a wavelength that is part of the electromagnetic spectrum its shorter than visible light waves.
Xylem and phloem help transport nutrition