Topic2: Basic Plant Structures, and Different types of plant cells

        While you are throughout my tour, let's learn some biology facts of plants. The basic plant structures are roots, stems, and leaves. Root is an organ that anchors a vascular plant in the soil, absorbs minerals and water, and often stores carbohydrates. Taproot, lateral roots, and root hairs are in the root system: taproot consists one main vertical root and develops from an embryonic root; root hairs grow by the thousands just behind the tip of each root, it increases the root's surface area. Stem is an organ that raises or separates leaves, exposing them to sunlight, also rise reproductive structures, facilitating dispersal of pollen and fruit. Each stem consists of an alternating system of nodes, the points at which leaves are attached, and internodes, the stem segments between nodes. In the upper angle formed by each leaf and the stem is an axillary bud, a structure that can form a lateral shoot, commonly called a branch. Most of the growth of a young shoot is concentrated near the shoot tip, which consists of an apical bud, or terminal bud, that is composed of developing leaves and a compact series of nodes and internodes. Plant cells differ structurally from the cells of most other organisms in a few key ways. Specifically, they are usually larger than animal cells and are surrounded by a rigid cell wall made from cellulose. They also often have a large central vacuole that takes up most of the cell, and if they carry out photosynthesis, the cells will have chloroplasts. This does not mean that all such cells are the same, and in fact, there are a number of different types of cells found in most plants. Plants basically have three types of tissues, which are made up of different types of cells. Surface tissue forms the protective outer layer covering the plant. Fundamental, or simple tissues, are usually only composed of one type of cell and are normally grouped based on the level of thickness of the cell wall. Vascular tissues are complex tissues that consist of more than one type of cell. There are only two types of vascular tissue: xylem and phloem. The surface tissue, or epidermis, of a plant is often only one cell thick, although it can be much thicker if the plant lives in a very dry environment and protection from water loss is crucial. It is made up of epidermal cells, which often have a very large vacuole. The cell wall that faces the outside of the plant is often thicker than cell wall that faces into the plant. Epidermal cells in the leaves may be specialized as guard cells. These cells control the opening and closing of small holes in the leaves, called stomata. In this way, they regulate the movement of gases into and out of the plant. The function of epidermal cells that line the roots is water absorption from the soil. To increase the surface area, many epidermal cells grow long hair, or filaments, from their surface. There are several types of fundamental tissues, including parenchyma, collenchyma and sclerenchyma. Parenchyma is made up of parenchyma cells and occurs in the roots, leaves and stems of plants. These plant cells are relatively unspecialized and contain large vacuoles and a thin cell wall. Within the leaves and stems, most of the chloroplasts are found in parenchyma cells. They give the cells their green color and allow photosynthesis to take place.

        Here is the diagram of my plant's basic structure: