Centrioles- Definition, Structure, Functions and Diagram

Centrioles- Structure and Functions

Centrioles Definition Eukaryotic cells contain two cylindrical, rod-shaped, microtubular structures, called centrioles, near the nucleus. They lack a limiting membrane and DNA or RNA and occur in most algal cells (a notable exception being red algae), moss cells, some fern cells, and most animal cells. They are absent in prokaryotes, red algae, yeast, cone-bearing and flowering plants (conifers and angiosperms) …

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Chloroplasts- Definition, Structure, Functions and Diagram

Chloroplasts- Structure and Functions

Chloroplasts Definition The word chloroplast is derived from the Greek words chloros, which means green, and plastes, which means “the one who forms”. Chloroplasts are a type of membrane-bound plastids that contain a network of membranes embedded into a liquid matrix and harbor the photosynthetic pigment called chlorophyll. It is this pigment that imparts a green color to plant parts and serves to …

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Cytoplasm- Definition, Structure, Functions and Diagram

Cytoplasm- Structure, Components, Properties, Functions

Cytoplasm Definition The cytoplasm is the semi-viscous ground substance of the cell. All the volume of such substance outside the nucleus and inside the plasma membrane is cytoplasm. It is sometimes described as the non-nuclear content of the protoplasm. All the cellular contents in prokaryotes are contained within the cell’s cytoplasm. In eukaryote organisms, the nucleus of the cell is separated from the …

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Golgi Apparatus- Definition, Structure, Functions and Diagram

Golgi Apparatus- Structure and Functions

Golgi Apparatus Definition The Golgi apparatus or the Golgi body or Golgi complex or simply Golgi is a cellular organelle present in most of the cells of the eukaryotic organisms. It is referred to as the manufacturing and the shipping center of the cell. Golgi is involved in the packaging of the protein molecules before they are sent to their destination. These organelles help …

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Cilia and Flagella- Definition, Structure, Functions and Diagram

Cilia and Flagella- Structure and Functions

Cilia and Flagella Definition Cilia and Flagella are complex filamentous cytoplasmic structures protruding through a cell wall. They are minute, especially differentiated appendices of the cell. Flagella (singular = flagellum) are long, hair-like structures that extend from the plasma membrane and are used to move an entire cell. Cilia (singular = cilium) are short, hair-like structures that are used to …

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Cell Wall (Plant, Fungal, Bacterial)- Structure and Functions

Cell Wall (Plant, Fungal, Bacterial)

Cell Wall Definition The cell wall is a rigid and protective layer around the plasma membrane which provides mechanical support to the cell. It is a non-living structure which is formed by the living protoplast. Animal cells do not have a cell wall. They are present in most plant cells, fungi, bacteria, algae, and some archaea.  In-plant cells, the cell wall is made …

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Mitochondria- Definition, Structure, Functions and Diagram

Mitochondria- Structure and Functions

Mitochondria Definition Mitochondria are oxygen-consuming ribbon-shaped cellular organelles of immense importance floating free throughout the cell. They are known as the “powerhouse of the cell” since these organelles supply all the necessary biological energy to the cell by oxidizing the substrates available. The enzymatic oxidation of chemical compounds in the mitochondria releases energy.  Since mitochondria act as the power-houses, they …

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Cell (Plasma) Membrane- Structure, Composition, Functions

Cell (Plasma) Membrane

Cell (Plasma) Membrane Definition Membranes are lipid structures that separate the contents of the compartment they surround from its environment. Plasma membranes separate the cell from its environment while other membranes define the boundaries of organelles and provide a matrix upon which complex chemical reactions can occur. The plasma membrane, also known as the cell surface membrane or plasmalemma, defines …

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