Question

Differentiate Fusiform initials and ray initials.

Answer 1

Hint: The vascular cambium has two types of cells known as fusiform initials and ray initials. Cork cambium arises as a concentric layer that forms a cylinder of dividing cells called as phellem and phelloderm. Phellogen is defined as the meristematic layer of cells that is responsible for the development of the periderm. The cells that grow in inwards direction from there are called phelloderm and cells that grow outwardly are called phellem. So, phellem is formed on the outer side of cork cambium whereas on inner side of cork cambium phelloderm is formed.

Complete answer:
The vascular cambium has two types of cells known as fusiform initials and ray initials. Fusiform cells are elongated and ray cells are rectangular in shape.

Fusiform initials	Ray initials
Fusiform initials are elongated cells and are arranged as bricks.	Ray initials are rectangular in shape and are shorter cells.
Fusiform initials cell give rise to secondary xylem and phloem.	These ray initials help in formation of phloem and xylem rays.
Secondary xylem is a wood portion as it is towards the inside and one formed outside the cambium is secondary phloem. This is what happens when fusiform initials divide.	Ray initials are cells that remain in the meristematic region after cellular division and they continue to make further more cells and form rays as because when growth continues cells move away from vascular cambium
It forms a vertical system of secondary xylem and phloem.	These form the horizontal system that stores food and water and helps in translocation.

Note: Cork cambium and vascular cambium are secondary meristems that are found in roots and stems when the tissues of the primary plant body have differentiated. Vascular cambium is responsible for increasing the diameter of the stems as well as roots and for forming woody tissue. On the other hand, cork cambium produces some of the bark.