Simple and Complex tissues

The plant possesses tissue levels of organisms. These issues are of different types based on the ability of the division present in the cells of the tissue. They are meristematic and permanent. Meristematic cells have the ability to divide and permanent cells represent the cells in their maturation phase.  Meristematic tissues are divided into three on the basis of the position. They are apical meristem, lateral meristem, and intercalary meristem. This permanent tissue is divided into simple and complex. Simple tissues are those which consist of one kind of cell. Complex tissues are those which contain different kinds of cells within a single tissue as they perform a definite function altogether. Permanent tissue acquires the division of labor and therefore is more organized than that meristematic tissue.

Definition of simple permanent tissue and complex permanent tissue:

Permanent tissue is divided into simple and complex. Simple tissues are those which consist of one kind of cell. Complex tissues are those which contain different kinds of cells within a single tissue as they perform a definite function altogether. Simple tissues consist of parenchyma, collenchymas, and sclerenchyma whereas complex tissue consists of xylem and phloem.

Simple tissue:

Permanent tissue is divided into simple and complex. Simple tissues are those which consist of one kind of cell. Simple tissues consist of parenchyma, collenchymas, and sclerenchyma

Parenchyma: This tissue consists of isodiametric cells with intercellular spaces. These cells are loosely bound and can be found in almost every part of the plant body. These tissues provide support to the body. Along with that, some of them consist of chlorophyll and can perform photosynthesis. These parenchyma cells are known as chlorenchyma. Some of the cells provide buoyancy to the aquatic plants, this type of parenchyma is known as aerenchyma. In the roots, these parenchyma cells perform the function of storage of starch and sugar and are known as pith. Parenchyma is also a part of complex permanent tissue that is xylem and phloem. 

Collenchyma: Collenchyma cells just like parenchyma cells lack a secondary cell wall but have a primary cell wall. These cells are long and have the ability to elongate and can get stretched. Because of this ability, the cells can provide structural support to the plant body. These cells are abundantly present in the stem of the plant body.

Sclerenchyma: The cells of sclerenchyma have a secondary cell wall and have lignin deposition on the cell wall of the cells. This is one of the essential components of wood. These sclerenchyma cells cannot stretch themselves but provide structural support to the plant body. These cells are dead and have no intercellular spaces at all. 

Complex permanent tissue:

Complex tissues are those which contain different kinds of cells within a single tissue as they perform a definite function altogether. They consist of xylem and phloem. Xylem and phloem come under vascular tissue and the first plant consisted of vascular tissue as pteridophytes.

Xylem: Xylem consists of four kinds of cells. These are tracheids, trachea, xylem parenchyma, and xylem fiber. All these are dead cells except xylem parenchyma. The tracheids and trachea are specialised cells and mainly help in the conduction of water and minerals. In the case of gymnosperms, tracheids are the only conducting cells. There are some perforations in the cell wall of tracheary elements that allow rapid conduction of water through the pores. Xylem fibers cells provide mechanical support whereas xylem parenchyma supports tracheary elements and xylem fiber and stores food.

Phloem: Phloem also consists of four kinds of cells. They are sieve elements, companion cells, phloem parenchyma, and phloem fiber. These are living cells except phloem fiber. The sieve elements consist of sieve tubes and sieve cells and are mainly related to the translocation of food from source to sink. The cells have a sieve-like structure in the cell wall that’s why this name. The companion cells support the sieve elements as they lack a nucleus. The phloem fiber just like the xylem supports the plant body and phloem parenchyma is used for the storage of food. 

Conclusion:

The plant possesses tissue levels of organisms. These issues are of different types based on the ability of the division present in the cells of the tissue. They are meristematic and permanent. This permanent tissue is divided into simple and complex. Simple tissues are those which consist of one kind of cell. Complex tissues are those which contain different kinds of cells within a single tissue as they perform a definite function altogether. Simple tissues consist of parenchyma, collenchymas, and sclerenchyma whereas complex tissue consists of xylem and phloem.