Provide the full forms of the following abbreviations:
$(1)$ $LHC$
$(2)$ $PS$

(N/A) $(1)$ $LHC$ stands for Light Harvesting Complex. It consists of hundreds of pigment molecules bound to proteins.
$(2)$ $PS$ stands for Photosystem. It is a functional unit of photosynthesis,consisting of a reaction center surrounded by light-harvesting complexes.