Botany

Botany is the branch of science that deals with the study of plants, their structures, biochemical processes, and properties. The plant classification also comes under botany along with plant disease and the interaction of plants with their surroundings. Different branches of science in which the study of botany has been applied are agriculture, forestry, and horticulture. The plant possesses a tissue level of organization and plays an important role in the environment. Different processes like transpiration, photosynthesis, etc. are important for the maintenance of balance in the environment.

History:

Theophrastus is considered the father of botany. Pedanius Dioscorides is an important writer in botany after Theophrastus. He described more than 600 kinds of plants. The naming of plants is determined by the international code of botanical nomenclature. The names of the plants are considered after the 10th edition of Species Plantarum written by Carolus Linneaus.

Plant Anatomy

According to the ability of division, the tissues can be divided into two groups- meristematic and permanent. Meristematic tissues are those which have the ability to grow and divide. On the other hand, permanent tissues are those which attain the maturation phase and have lost the ability to divide further. 

The meristematic tissues are further divided into different parts according to different topics. According to the position, meristematic tissues are of three types- apical meristem, lateral meristem, and intercalary meristem.

Apical meristem: 

This tissue is present on the apex part of the plant. This helps in elongation in length. They form growing parts at the apices of roots and stems and are responsible for the increase in length, also called primary growth.

Lateral meristem: 

This tissue is present on the two sides parallel to the axis of the plant. This tissue helps in the expansion of the girth and diameter of the plant.

Intercalary meristem: 

This tissue is present between two permanent tissues, generally in the internode. This also helps in the linear elongation of plants and increases in the length of the internode.

Permanent tissues can be divided into simple and complex. Simple permanent tissues have the same type of cells and can be categorized as parenchyma, collenchymas, and sclerenchyma.  

Parenchyma: 

The tissue consists of simple alive, polygonal cells with intercellular cells and consists of the chloroplast. Parenchyma along with chloroplast is known as chlorenchyma. Some parenchyma cells provide buoyancy to some water plants and therefore, are known as aerenchyma. A wide range of parenchymatous tissues can store starch in fruits and vegetables.

Collenchyma: 

These are stretched-out cells with small intercellular gaps. The cell wall of this tissue consists of pectin and cellulose. Collenchyma provides support to the plants. There are different depositions on the cytoplasm of collenchymas, based upon which it is divided into three. Three types of collenchymas are annular, angular, lacunar.

Sclerenchyma: 

This tissue has dead cells with lignin deposition in the cytoplasm of the cells. These cells have no intercellular gaps. This type of tissue is quite common in seeds and nuts. This tissue provides strength to the plants.

Complex permanent tissue consists of different cells and can be categorized as xylem and phloem.  

Xylem: 

Xylem consists of four types of cells and it consists of dead cells except for xylem parenchyma. Xylem helps in the transportation of water and minerals. Therefore, transportation that occurs through the xylem is unidirectional. Four cells of the xylem are tracheids, trachea, xylem parenchyma, and xylem fiber.

Phloem: 

Phloem consists of four types of cells and consists of living cells except for phloem fiber. These cells are sieve tubes, companion cells, phloem parenchyma, and phloem fiber. This tissue helps in the translocation of food from the source to the sink of the plants. Therefore, transport through phloem is multidirectional. 

There are some protective tissues that provide protection to the plants which include cork and epidermis.

Epidermis: 

This tissue forms the outer covering consisting of a layer of cells. There is stomatal perforation in the epidermis in some places, by which the exchange of gases occurs. 

Cork: 

This is the external protective tissue, which substitutes the epidermal cells in mature roots and stems. The cells have no intercellular gaps and are dead. Their cell wall consists of suberin which makes the cells impervious to water molecules and gas. 

Plant morphology:

The morphology of plants has a wide range of structures. These consist of roots, stems, leaves, flowers, fruits, and seeds. 

Roots: 

The roots can be of two types. They are taproot and fibrous roots. Along with that, there is another type of root known as adventitious root which forms from a place other than radical. Roots perform different functions like storage, absorption of water, and miners and anchorage. According to these functions, roots can be differentiated into different types. The different parts of the ideal root are the permanent region, the region of elongation, meristematic region, and root cap region.

Stem: 

A stem develops from the plumule of the seed. The stem bears leaves, flowers, and fruits. The different forms of stems are runners, suckers, tubers, climbers, tendrils, rhizome, cladode, phylloclade, thorns, and so on, based on different functions performed by the stem.

Leaves:

 Leave is a lateral flattened structure. This is the essential photosynthetic structure of plants and consists of stomata which involve the exchange of gases. The different parts of the leaf are the leaf base, petiole, and lamina. Leaves can be divided into simple and compound leaves based on the pattern present in the leaf blade. Some modifications of leaves are spines, leaf tendrils, and so on.

Flowers:

The flower represents the reproductive part of the plant. The arrangement of flowers in the axis is known as inflorescence. 

Conclusion:

Botany is the branch of science that deals with the study of plants, their structures, biochemical processes, and properties. Theophrastus is considered the father of botany. The plant possesses a tissue level of organization and plays an important role in the environment. According to the ability of division, the tissues can be divided into two groups- meristematic and permanent Morphology of plants has a wide range of structures. These consist of roots, stems, leaves, flowers, fruits, and seeds.