Thick rigid cell wall is not characteristic of a parenchyma cell
Parenchyma is the answer because whereas the other two, xylem and phloem are vascular tissues, parenchyma is a packing tissue.
Well first, your immune system has two main halves, innate and adaptive... the innate is the line of defense to fight off disease and bacteria, which is made up of anatomical barriers
Nervous system is divided into parasympathetic and sympathetic
The number of neutrons in each atom
