Complete Plant Cells and Functions
Plant Cells: Types, Parts, Images and Complete Functions - Do you know what is meant by plant cells ?? If you don't know it, you are absolutely right to visit gurupendukasi.com. Cells are the smallest units of living things. In cells there are protoplasms composed of carbohydrates, fats, proteins, and nucleic acids. Based on the type of cell, it is divided into procharotic, which is a cell that does not have a core membrane and eukaryotic cells, ie cells that have a core membrane.
From the discovery of the cell and all its activities, the cell theory was born, that the cell is a structural unity, functional unity, growth unity, the necessity of heredity, and reproductive unity of living things.
Structurally the cell is a constituent of living things, part of the cell including the plasma membrane, nucleus, and cytoplasm. Plasma membranes are composed of lipoproteins, which are bonds between fat and protein.
Nucleus have nucleoli which function for ribosome synthesis, the nucleus functions to control cell activity. Cytoplasm contains cell organelles, such as the reticulum, endoplasm, ribosomes, golgi bodies, libosomes, mitochondria, microtubules, microfilaments.
Understanding Plant Cells
Plant cells are a group of eukaryotic cells, eukaryotic cells are groups of cells that have genetic material (DNA) that is wrapped or wrapped by a membrane. Plant cells have a unique structure compared to other eukaryotic cells. The most basic difference is the rigid form of plant cells. This form is obtained from the outermost cell wall in the plant cell. The cell wall is composed of cellulose, pectin, hemicellulose, and lignin compounds which will strengthen the structure of plants.
Although animals and plants both have eukaryotes, they differ in certain characteristic features. For example, plant cells have well-developed cell walls and large vacuoles, whereas animal cells do not have these structures. Apart from differences in structure, in animal cells there are centrioles and middle filaments which are not found in plant cells.
Characteristics of plant cells that consist of organelles and cytoplasm, where all organelles (except the cell nucleus or neucleus) and subcellular structures in the cytoplasm will be covered by cell membranes or cell walls as a protective layer.
Types of Plant Cells
1. Parenchyma cells
Parenchyma cells are cells that have several functions ranging from storage, support to photosynthesis, where the phloem is bound. In addition to xylem and phloem that are bound to parenchyma cells, leaves also consist of parenchyma cells. Some parenchymal cells, such as the epidermis, function for light penetration and regulate gas exchange. Parenchymal cells have thin and permeable cell walls that allow the transport of small molecules in them.
Parenchyma cells can also grow into thorns which prevent herbivorous animals from eating them. Parenchyma cells that contain a lot of chloroplasts and play an important role in the process of photosynthesis are called chlorenchymal cells. Most parenchymal cells in potato tubers and cotyledons from legume seeds have a storage function.
2. Colenchyma cells
Colenchymal cells live as adults and only have a primary wall. These cells are mature and originate from meristems which initially resemble parenchymal cells. The plasticity does not develop and the secretory organelles (endoplasmic reticulum and golgi body) proliferate to remove additional primary walls. This wall is thick in the corners where three or more cells touch each other and thin in a part where only two cells touch.
Pectin and hemicellulose are the main contents of the collenchyma cell wall of open seeded plants (angiosperms). Colenchyma cells are usually quite elongated and transverse. The aim is to provide flexibility. The cell wall does not contain lignin so it becomes rigid.
3. Sklerenkim cells
Sclerenkim cells are hard and tough cells that give strength to plants. This cell consists of sclereid and fiber. There is a secondary wall that contains lignin so it is waterproof. Thus, these cells cannot last long because they cannot exchange substances to carry out metabolism. Sclerenkim cells will usually die at a certain time, cytoplasm will disappear, and leave the cavity empty.
4. Xylem cells
Xylem cells are cells that have lignified cell walls. This cell functions to transport water and nutrients from the soil (roots) to the leaves to carry out photosynthesis. Xylem cells first appeared in plants since 425 million years ago.
5. Phloem cells
Phloem cells are cells that make up special tissue for the transportation of nutrients in higher plants. Which is transported mainly sucrose. Phloem cells consist of two types of cells namely filter tubes and companion cells. In the sieve tube there is no cell nucleus and the ribosome and its metabolism is regulated by companion cells. Meanwhile, companion cells are connected to sieve tubes through plasmodesmata. Moss has no phloem.
6. Epidermal cells
Plant epidermal cells are special parenchymal cells found on all surfaces of leaves, stems and roots.