Cell Wall This is the layer that surrounds the plant cell which is made up of fibres of cellulose , hemi cellulose, pectin and proteins. This outer protective layer is very thick and rigid that provide strength to the plant body.Cell Membrane This is the thin layer inner to the cell wall. It is made up of lipids and proteins that surrounds the cytoplasm and is semi permeable .Cytoplasm The plant cell anatomy reveals the appearance of cytoplasm. It is fluid in which cell organelles like endoplasmic reticulam, golgi apparatus, mitochondria, plastids etc... are distributed and also acting as the site for various cellular activities.Endoplasmic reticulam: It is a network of tiny tubular structures scattered in the cytoplasm acting as a channel for transporting materials.There are two types of endoplasmic reticulam- ribosome bearing -Rough Endoplasmic Reticulam (RER) and without ribosome-Smooth Endoplasmic Reticulam(SER).Golgi apparatus-It is flattened ,disc-shaped sac or cisternae arranged parallel to each other.Its function is packaging and delivery of materials inside or out side the cells.Lysosomes-They are membrane bound vescicular structures containing highly active hydrolytic enzymes capable of digesting carbohydrates,proteins,lipids and nucleic acids.But found rarely in plant cells..Vacuoles-These are membrane bound organelles containing water,sap, excretory products and other useful substances needed for the cellular activities. Its outer membrane is called tonoplast.In young plant cells small vacuoles are present while the older plant cells are identified with a big vacuole.Mitochondria-Cylindrical or sausage shaped organelles act as sites for cellular respiration.It is with a double membrane and the outer membrane is the smooth limiting membrane and inner membrane form infoldings called cristae in to the matrix to increase the surface area for respiration. Here energy is produced in the form of ATP molecules and stored . Hence they are called ' power houses' of he cell.It contains a circular DNA in its matrix.PLASTIDS-Three types of plastids present-chloroplast,chromoplast and leucoplast.Chloroplasts contain chlorophyll pigments that trap light energy for photosynthesis. Chromoplasts are the plastids that give colour to the flowers and other parts.Leucoplasts are the colourless plastids present in roots.Plastids are also double membraned structures contain the matrix called stroma in which flattened membranous sacs called thylakoids ,arranged as stalks called grana.This also contains circular DNA.Ribosomes-Granular structures composed of RNA and act as sites for protein synthesis.Cytoskeleton-Plant cell anatomy shows some proteinaceous filamentous net work in the cytoplasm which provides mechanical support and maintain the shape of the cell.Nucleus--In the study of plant cell anatomy the important structure locating as the centre for controlling cellular activities is the nucleus. The nuclear membrane is double layered that covers the nucleoplasm which contains chromatin fibres (chromosomes) and nucleolus. Chromosomes are the structures made up of DNA -- the heriditary units.
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