Fill in the blanks with the terms given in the box below: Nucleus, chromosomes, cell wall, cell membrane, protoplasm, cytoplasm, ribosome, cell organelles The outermost layer of plant cells is the ___(a)___ beneath which is the ___(b)___ The term ___(c)___ refers to the jelly-like substance containing all the ___(d)____. The ___(e)___ contains thread-like structures called ___(f)___.