Bulliform cells are found in the epidermis of bamboo leaves, which is a grass. These cells cause leaves to roll up during water stress.

Pitted thickening is seen in metaxylem. In pitted, tracheids are uniformly thickened, except for small unthickened area called pits.

Passage cells are found in root endodermis. They are thin walled cells just opposite to protoxylem patches that help in passage of water from cortex to xylem.

Radial vascular bundles are found in dicot and monocot roots. This is the most primitive type of vascular bundle. In radial vascular bundles, xylem and phloem lie on separate radii.

Exarch development is seen in vascular plants. There are one or more primary xylems in stems or roots and the xylem develops from the outside inwards towards the centre.

The secondary thickness is in the form of cross bands in reticulate type of tracheids.

Both, dictyostele and solenostele arrangement of vascular bundles are seen in ferns.

Xylem parenchyma stores food. These are found in between the vessels and the fibers.

Xylem parenchyma is the only living component of xylem tissue. It is represented by groups of parenchyma cells that are found in between the vessels and the fibers. They are meant for storage of reserve food.

Plectostele is a protostele in which plate-like regions of xylem appear in transverse section surrounded by phloem tissue.

The Centrarch pattern was common in early land plants, such as rhyniophytes, but is not present in any living plants.

Pericycle, which if present, defines the outermost boundary of the stele.

The metaxylem is closest to the centre of the stem or root and the protoxylem to the periphery in exarch pattern of protoxylem and metaxylem arrangement.

A tylosis is a bladder-like distension of a parenchyma cells into the lumen of adjacent vessels in wood.

The glands containing essential oils from the skin of citrus fruits are lysigenous cavity, they are formed by destruction or dissolution of cells. Oil glands are found in lysigenous cavity.