Question

Arrange the following in the order of their location from the periphery to center in the entire dicotyledonous plant body.
(a) Fusiform cells
(b) Trichoblasts
(c) Collocytes
(d) Tylosis
(b), (c), (a), (d)
(a), (d), (c), (b)
(d), (a), (b), (c)
(c), (b), (a), (b)

Answer 1

Hint:The dicotyledonous plant has a series of layers starting from the cortex, periderm, primary and secondary phloem, vascular cambium, spring and Autumn wood, annual ring, sapwood, heartwood, and primary xylem. Trichoblasts are cells present on the root hairs, followed by the collocytes, which are the cells of the collenchyma present in the secondary phloem, followed by fusiform cells that are present in the vascular cambium, and finally by the tyloses which are balloon-shaped structures present in the heartwood.

Complete step by step answer:The organizational setup of the different layers of a dicot plant begins with the root hairs and ends with the inner stem medulla. The series of layers are as follows:

Fusiform cells or also known as fusiform initials are specialized cells that elongate to form the secondary xylem and secondary phloem during secondary growth. These cells are present in the vascular cambium where they divide to produce secondary xylem towards the inside of the cell and the secondary phloem towards the outside of the cell.
Trichoblast cells are specialized cells present on the exterior surface of a plant’s root that is responsible for forming root hairs. A plant’s roots are covered in trichoblast cells to ensure root growth and development and are often referred to as root fuzz as they increase the surface area of the root hairs allowing them to increase nutrient uptake.
Collocytes are cells present in the collenchyma of the plant which imparts mechanical support. This is found in the hypodermis of the cortex of the plant.
Tyloses are balloon-like structures that bulge through the circular bordered rings of vessels of the heartwood and block water movement.
By understanding the functions and location of these cells it is evident that the correct option is A.

Note:The entire organizational setup mentioned is for dicotyledonous plants where the periderm is a combination of the phellem, phellogen, and phelloderm. The collenchyma and parenchyma are non-living tissues that serve mechanical purposes or aid in the function of either the xylem or phloem. The pitch denoted here is the medulla where the water is taken up by the plant and is transported to other parts of the plant.