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Plant Cell



Higher plants composed by a number of cell bodies, both living cells and dead cells. Living cells have similarities and differences in structure and function. The equation is a cell that has diniding cells, plasma filled wrapped by the plasma membrane. While the difference is mainly caused by environmental and genetic factors, which caused the differentiation process that follows the process of cell division.

Cell Wall

The cell wall consists of: lamela middle, primary wall and secondary wall. Between adjacent cells was lamela middle sei glue between the two walls together. Lamela middle consist mainly of Ca-pektat a gel. Primary wall is a layer formed during Expansions, composed of hemicellulose, cellulose, pectin, fats, and proteins. Secondary walls usually thicker than the primary wall composed mainly of cellulose and lignin sometimes, an added layer after the process is complete the cell wall Expansions.

Not all parts of the cell wall thickening and charged plasma (plasmodesmata). Have the number of primary wall thinning area called dot. This area has a high density plasmodesmata. Plasmodesmata are cytoplasmic thin braid through the walls of adjacent cells, connecting adjacent cell protoplasts. Thus, the cell walls become perforated allowing chemicals to pass through.

Cell wall immediately adjacent to the outdoor air is often coated kutin and suberin (cuticle). This layer is not completely sealed so it still allows chemicals to pass through. The cell wall serves to provide mechanical strength so that the cells have a fixed shape and provide protection for the contents of the cell, and because of the nature hidrofilnya can hold water and move water imbibition and compounds dissolved in it to protoplasts.

2. Protoplasts

Protoplasts is a living part of the plant cell, although there are the various inorganic compounds. Protoplast consists of four main parts, namely: sitgplasma, nucleus, vacuole and materials ergastik.

3. Cytoplasm

The cytoplasm is the cell complex, a liquid material which contains many molecules, including colloidal suspension and membranous organelles. Cytoplasm and the nucleus together is called protoplasm. Some plant cells also have too pure substances that do not live called ergastik materials, such as calcium oxalate, protein items, gum, oil, resin.

Endomembrane system in the cytoplasm include the endoplasmic reticulum, Golgi bodies, covers the core, and cell organelles and other membrane (micro entities, sferosom and vacuole membrane) derived from the endoplasmic reticulum or Golgi bodies. While the plasma membrane is considered a separate unit, despite growing through the addition of a number of bags from the Golgi body.

Mitochondria and plastids are blanketed by a layer of smooth membrane and the membrane in a curved-dent is also not related to the membrane system. Similarly ribosome, microtubule and microfilaments are not part of the endomembrane system.

4. Plasma Membrane

The plasma membrane regulates the flow of solutes in and out of cells, and regulate the flow of water through osmosis. Differential plasma membrane is permeable, meaning that it can pass certain chemical compounds and other compounds pass.

The plasma membrane is a lipid with the duplicate layer. Hydrophilic (water loving) lipid molecules on the surface. The lipophilic portion (like fat), the molecule is facing the dual layer causing a bright room. Protein molecules which covers 50% immersed in the lining membrane materials that duplicate, with one or both ends protruding to one or both surfaces of the membrane. Both the membrane surface is typically different.

5. Endoplasmic reticulum (ER)

In many cells, RE resembles a bag that folds flat (called sisternae). RE to form transport systems for a wide variety of molecules within cells and between cells even meialui plasmodesmata. Numerous ribosomes are associated with RE in terms of protein synthesis. RE RE plastered called ribosomes rough. RE subtle innocence-ribosomes and tubular.

6. Golgi Apparatus

With electron microscopy, Golgi bodies (diktiosom) visible as a stack of flat plates hollow inside (sisternae) with the edge of a bloated and surrounded by flat objects (vesicles). Golgi bodies berperarudalam plasma membrane formation and transport of enzymes to be made in the cell, which determines the chemical reactions that occur and determine the structure and function of cells.

7. Blankets core (nucleus)

Blankets core (nucleus) surrounded by two parallel unit membranes called core quilt. The thickness of the outer membrane of a little thicker than the inner membrane. Both are separated by a space perinukleus. Blankets core has many pores. Inner and outer membranes together to form a pore periphery, which is maintained by the shape of a material resulting in a structure called the annulus. RE relate to the core blanket, being perinukleus space is continuous with the space between the membranes parallel to RE.

8. Vacuoles

Vacuole resembles plasmalemma, but distinct functions and are slightly thinner. Tonoplas solute transport out of the vacuole, thus controlling the water potential.

9. Micro Agency

Micro entity is wrapped round organelle membrane layer, grainy next to it, and sometimes accompanied by protein crystals. Two types of micro entities is important glioksisom peroxisomes and each plays a special role in the chemical activity of plant cells. Perpksisom outlines glycolic acid produced from fostosintesis, other molecules recycle back to the chloroplast. Glioksisom down fats into carbohydrates during and after seed germination. Hydrogen peroxide reaction products are also described in glioksisom.

10. Ribosomes

Protein synthesis is vital cell functions that take place in thousands of ribosomes. Ribosomes are scattered in the cytoplasm or join RE rough in the cell, and is always on the side of the membrane cytosolic dual RE. Ribosomes are also attached to the membrane of the nucleus in the blanket iuar cytosol. Ribosomes appear as black spots on electron micrographs. Often also form a chain like strands, especially in a spiral pattern (twisted). This structure is called poliribosom or polisom. In the ribosome, the genetic information of the mRNA is translated into proteins.

11. Mitochondria

In light microscopy, the mitochondria look like spheres, rods or wire small variety of shapes and sizes. Membrane-enclosed dual, outer surface holes were forming inside surface bumps (kristae) into the stroma. Membrane

In the matrix wraps, and many enzymes that control the various stages in cell respiration and metabolism in particular are generally found there or in the matrix. Mitochondria have DNA and ribosomes small inside the matrix, so that they can synthesize their own porteinnya.

12. Plastids

Lens-shaped plastids are organelles found in all plant cells, covered by a dual membrane system. Plastids contain DNA and ribosomes are immersed in a liquid matrix called the stroma. Plastids formed from the division of plastids former or as a result of differentiation proplastida. Colorless plastids called leukoplas, eg amiloplas containing grains of rice or proteinoplas containing protein reserves. There are two kinds of colored plastids, the chloroplasts that contain chlorophyll and other pigments that accompany it, and kromoplas containing other pigments (carotenoids). Plastids are chloroplasts important, as a venue for photosynthesis.

Chloroplasts contain a system mebran called thylakoids, which often connect-connect to form stacks called grana membranes. Grana immersed in the stroma. Enzymes that control photosynthesis found in the thylakoid membrane and in the stroma.

13. The nucleus

The nucleus is the control center of the eukaryotic plant cell. The nucleus controls all cell functions to determine various chemical reactions as well as the structure and function of cells. The nucleus is round or elongated organelles whose core wrapped in a blanket. Plasma nucleus (nukleoplasma) is grainy colloidal systems, containing chromatin in cell division turned into a chromosome. The function of chromosomes is formed m-RNA that regulates protein synthesis. In the plasma there is also a nucleolar nucleus of every cell numbers characteristic for each species. Nucleolus is dense, irregular shapes, a mass of fibers and granules, and dark. The function of the nucleolus is to synthesis of r-RNA and ribosomes.

14. Vacuoles

Distinctive bodies other than the cell walls of plant cells and plastids are vacuoles. Vacuoles do some functions. Shape and tissue tension has only a primary wall is due to the presence of water and dissolved materials are pressed from the vacuole. The pressure caused by osmosis. Solute concentration in the vacuole is quite high, including salts, small organic molecules, some protein (enzyme) and other molecules. Some vacuoles contain pigments that cause colors in many flowers or Dauh. In some parts of the plant, the vacuoles may contain ingredients that may be harmful to the cytoplasm.

Young cells that actively divide in the growing point of the stem and roots have very small vacuoles. Largely formed from the ER, and grew up with the cell, taking water by osmosis and join each other. Adult cells often have a vacuole that fills 80-90% or more of the cell volume, and protoplasmanya tersisiih until only a thin layer between tonoplas and plasmalemma. Some of the active cell can divide large bervakuola.

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