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The plant cell


THE plant cell is similar to the animal cell but contains some peculiarities such as the cell wall and the chloroplasts. It is divided into:

- Protoplasmic componentswhich are a compound of organelles cell phones and other structures that are active in cell metabolism. Includes the nucleus, endoplasmic reticulum, cytoplasm, ribosomes, Golgi complex, mitochondria, lysosomes and plasts.

- Non-protoplasmic components, which are the residues of cellular metabolism or storage substances. Includes vacuoles, cell wall and ergastric substances.

It is a cavity bounded by a membrane (tonoplast) and contains the cell juice that is composed of ergastric substances and some in cells may contain pigments such as flavones and anthocyanins. Young cells usually have several small vacuoles that along their development fuse into one mega vacuole. They act in osmotic regulation by expelling water from the cell or can fuse to lysosomes and participate in the process of intracellular digestion. It originates from the golgi complex.

They are reserve substances or residues, products, of cellular metabolism.

  • Starch: are solid particles of various shapes, can be found in chloroplast or leukoplast. They form grains with many layers centered on a point called hilo.
  • Protein: Ergastric proteins are reserve material and present in the endosperm of many seeds in the form of aleurone grains.
  • Lipids: May occur in the form of oil or fat if it is for storage or in the form of terpenes which are end products such as essential oils and resins.
  • Tannins: a group of phenolic compounds that can stay in various plant organs (accumulate in vacuoles) and can impregnate the cell wall

It originates from protoplastid and has different configurations with several specialties:

Chloroplasts are chlorophyll plasts, responsible for the photosynthesis. They are only found in cells exposed to light. is formed by an outer membrane and an inner membrane that suffers invaginations forming stacked bags, the tilacoides. Some lay on top of each other forming a pile called granum (plural = money). The internal matrix is ​​called a stroma and may contain starch granules scattered throughout it. They are derived from chromoplasts. Chloroplasts have their own DNA and ribosomes, are relatively independent of the rest of the cell (especially the nucleus).

Chromoplasts They are colored plastids (containing pigments) of irregular structure that give rise to chloroplasts. Its main pigments are carotenoids (carrot coloring) and xanthophylls that give coloration to flowers and fruits.

Leukoplasts They are colorless and serve to accumulate various substances such as proteins, starches and lipids. Depending on the substance they accumulate, they are given different names: oleoplasts, proteoplasts, amyloplasts, etc.