A. In biology, tissue is a cellular organizational level between cells and a complete organ. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.‎B. A meristem is the tissue in most plants containing undifferentiated cells, found in zones of the plant where growth can take place. Meristematic cells give rise to various organs of a plant and are responsible for growth.

C. Dermal tissue basically is epidermal tissue made up of cells which are protective in function. It can be seen in stems, leaves and roots. These tissues make up the outer covering of the organism to protect the underlying tissues. They are also secretory in function in some organs. Dermal tissue is sometimes covered by another layer called as cuticle. Some cells of the dermal tissue possess stomata which are guarded by guard cells.