Animal Cell
Cytosol: is a viscous, semi transparent fluid in which the other cytoplasmic elements are suspended. It is a complex mixture with properties of both a colloid and a true solution. Dissolved in the cytosol, which is largely water, are proteins, salts, sugars, and a variety of other solutes.
Mitochondria: are spool-shaped organelles. these organelles have a spool form. In living cells, they almost continually wiggle, expand, and change shape. They supply the majority of the cell's ATP requirements, acting as its power plants. In a given cell, the density of mitochondria reflects the energy requirements of that cell because mitochondria are frequently gathered where the action is.
Mitochondria can replicate themselves and have their own DNA, RNA, and ribosomes. One percent of the proteins needed for mitochondrial functions are made by mitochondrial genes, and the nucleus of the cell's DNA contains the amino acid sequences for the rest of the proteins required for cellular respiration. The mitochondria either create new cristae or simply pinch in half (fusion) to increase their number, then expand to their previous size as ATP levels rise.
Plasma Membrane:the membrane that divides a cell's interior from its external environment and is present in all cells. Both lipids and proteins make up the plasma membrane. The phospholipid bilayer, which creates a permanent barrier between two aqueous compartments, is the membrane's basic structural component
Rough ER: The external surface of the rough ER is studded with ribosomes.
Ribosomes: are tiny, dark-staining granules made up of different types of RNA and proteins. Two globular subunits, one on each ribosome, fit together like the body and cap of an acorn. Some are connected to the rough endoplasmic reticulum, whereas others float freely in the cytoplasm. In addition to producing soluble proteins that are imported into the mitochondria and a few other organelles, free ribosomes also produce those that are used in the cytosol.
Function: A cell is protected by its cell membrane. Additionally, it offers a stable environment inside the cell. And that membrane serves a variety of purposes. One is to move compounds out of the cell that are harmful as well as nutrients into the cell.
It participates in the transmission of signals between the cell membrane, the nucleus, and organelles. It moves metabolites from the place where they are produced to other areas of the cell. When the cell splits in mitosis, it is crucial for cytokinesis. Eukaryote metabolism involves the cytoplasm.
Components and Functions>
Two membranes, each having the overall shape of the plasma membrane, envelop this organelle. The inner membrane folds inward to generate shelf-like cristae that protrude in the matrix, the gel-like substance found inside the mitochondria, in contrast to the outer membrane's smooth, featureless surface. Along with the properties of proteins and phospholipids
Function: Maintaining healthy membrane phospholipid compositions is essential for maintaining mitochondrial integrity and supporting regular cell functions.
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Function: Proteins made by membrane-bound ribosomes are either exported from the cell or used to build cell membranes. Depending on the kind of proteins being produced at any one time, ribosomes can adhere to and detach from the endoplasmic reticulum membranes.
Smooth ER: comprises of tubules arranged in a looping network and continues the rough endoplasmic reticulum. Protein synthesis is not aided by its enzymes. Instead, they stimulate the following processes' reactional processes.
Function: The ribosomes carry assembled proteins into the cell's fluid-filled interior. When finished, the new proteins are packaged into vesicles covered with coatomers and transported to the Golgi apparatus, where they are subjected to additional processing.
Function:
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Because the rough ER is prevalent and well established in the majority of secretory cells, antibody-producing plasma cells, and liver cells, which create the majority of blood proteins, ribosomes manufacture all proteins released by cells. Because integral proteins and phospholipids that are a component of all cellular membranes are produced there, this process is known as the "membrane factory." The exterior face of the ER membrane, where the necessary substrates are present, is where the enzymes' active sites for catalyzing lipid synthesis are located.
Lipid metabolism, cholesterol synthesis, and synthesis of the lipid components of lipoproteins. (liver cells)
Synthesis of steroid- based horomones such as sex horomones
Absorption, synthesis, and transport of fats
Detoxification of drugs, certain pesticides, and carcinogens
Breakdown of stored glycogen to form free glucose
Golgi Apparatus: The “traffic director” for cellular proteins Consists of stacked and flattened sacs, shaped like hollow dinner plates, associated with swarms on tiny membranous
function: is to modify, concrete, and package the proteins and lipids made at the rough endoplasmic reticulum.
Inside the organelle the proteins are modified: Some sugar groups are trimmed while others are added, and in some cases, phosphate groups are added. The various proteins tagged for delivery to specific address, sorted and packaged in at least three types of vesicles that bud from the concave transface of the Golgi apparatus.
Protein-filled vesicles that are meant for export break off from the trans face as secretory vesicles, or granules, which then move to the plasma membrane and exocytose their contents out of the cell. It separates the vesicles that are loaded with lipids and transmembrane proteins that are headed for the plasma membrane. Additionally, it stores digesting enzymes in cells' enduring membranous lysosomes.
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Peroxisomes: Are membranous sacs containing a variety of powerful enzymes , the most important of which are oxidases and catalases.
Function (Catalases) The crucial enzyme catalase uses hydrogen peroxide, a nonradical ROS, as its substrate. In order to maintain an appropriate level of the molecule in the cell, which is also required for cellular signaling activities, this enzyme is in charge of neutralizing hydrogen peroxide through its breakdown.
Function (Oxidases)To detoxify toxic chemicals like alcohol and formaldehyde, oxidases molecular oxygen. Free radicals, extremely reactive compounds with unpaired electrons that can disrupt the structure of biological molecules, are what it primarily neutralizes.
Cytoskeleton: “Cell skeleton” an elaborate network of rods running through the cytosol
It acts as a cell's bones, muscles , and ligaments by supporting cellular structures and providing the machinery to generate various cells.
Three types; microfilaments, intermediate filaments and microtubules.
Microfilaments: The cell surface is shaped by microfilaments that extend into the villi. Similar to rubber bands, microfilaments resist strain by thickening the cortex along a cell's inner border.
Intermediate filaments: Desmosomes allow intermediate filaments to link neighboring cells. Organelles are held in place by intermediate filaments, which are present throughout the cell.
Microtubules: From the centrosome, microtubules extend to the edges of the cell. In the interior of the cell, microtubules prevent compressive forces from changing the shape of the cell.
Centrosome and Centrioles
Composed of microtubules
The centrosomes (cell center), which serves as an organizing hub for microtubules, are located at one end of the cell next to the nucleus. Apart from a matrix with a granular appearance and centrioles—small organelles with a barrel shape that are placed at an angle to one another—it has a few additional unique characteristics.
Centrosome Matrix known for generating microtubules and organizing the mitosis spindle in cell division.
Each centriole is made up of nine triplets of microtubules organized in a pinwheel pattern and joined to one another by non-tubulin proteins to form a hollow tube. They serve as the cilia and flagella's bases.
Cillia and Flagella
Cilia are whip-like, motile cellular extensions that occur, typically in large numbers, on the exposed surfaces of certain cells. Ciliary action moves substances in one direction across the cell surfaces.
Centrioles, which are considerably larger than microtubules, project in the direction of the flagella. Multicellular and unicellular organisms travel from one location in the organelle to another.
Microvilli
are finger-like membrane protrusions, supported by the actin cytoskeleton. Microvilli on the surface of epithelial cells such as those lining the intestine increase the cell's surface area and thus facilitate the absorption of ingested food and water molecules.
Actin Filaments
that parallel one other and run the length of the building. Protein bundles associated to the actin filaments connect the filaments to one another and the cell membrane.
Villin: increasing intestinal absorptive surface area by 40 to 600 times, respectively, resulting in remarkably effective nutrition absorption in the lumen.
Fimbrin: alters how stress fibers and microvilli are organized in the cytoskeleton.
Nucleus: the head of the cell, also known as the boss of the cell.
Function: It carries the genes, structures that hold the genetic information, and its function is to manage and regulate the functions of the cell (such as growth and metabolism).
Nuclear Envelope, Nucleoli, and Chromatin
Nucleoli are dark staining spherical bodies found within the nucleus. They’re not membrane bounded and contain one or two nucleoli per nucleus or maybe more.
Associated with nucleolar organizer regions, which contain DNA that issues genetic information for synthesizing rRNA.
Nucleolus; is a ribosome factory, composed of deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein. A long ribosomal RNA (rRNA) precursor molecule is transcribed from DNA, processed into three mature RNAs, and packaged together with specific proteins to make the large and small ribosomal subunits.
The nucleolus is a spherical structure found in the cell's nucleus whose primary function is to produce and assemble the cell's ribosomes. The nucleolus is also where ribosomal RNA genes are transcribed.
Nuclear Envelope:Is the membrane inside the cell around the nucleus.
Composed of:
Nuclear Lamina
Nuclear Complex pores
Nuclear Membrane
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Nuclear Membrane: composed of two phospholipid bilayers. It acts as a barrier that separates the contents of the nucleus from the cytoplasm. Like other cell membranes, the nuclear membranes are phospholipid bilayers, which are permeable only to small nonpolar molecules
Nuclear Complex Pores: regulates the entry and exit of molecules and big particles into and out of the nucleus by establishing an aqueous transport channel at each pore.
Nuclear Lamina;a system of laminas that preserves the nucleus' structure and functions as a scaffold to arrange DNA inside the nucleus
Chromatin“Beads on a string” structure with nucleosomes
Composed of 30% of DNA, which is called our genetic material, about 60% globular histone proteins and 10% of RNA chains are formed
Molecules of the rRNA are synthesized, they are combined by two kinds of ribosomal units (Proteins are manufactured on ribosomes in the cytoplasm and imported into the nucleus) . Most of the Subunits leave the nucleus through the nuclear pores and enter the cytoplasm, where they join to form functional ribosomes.
<Histones
Lysine and arginine, two positively charged amino acid residues, make up histones. They serve a part in gene control in addition to provide a physical way to pack the extremely long DNA molecules in a compact, ordered manner.
Exocytosis:
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Nucleosomes
Nucleosomes are an organelle's basic building block. which is made up of eight histone protein clusters or flattened disc-shaped cores that are linked together by a DNA molecule like beads on a thread.
Excoytosis
is the final stage of the secretory route and it entails the fusing of vesicles with the plasma membrane. In fungi, this process makes sure that cell wall-synthesizing enzymes, membrane proteins, and lipids are delivered to areas of active growth.
The following objectives are achieved via exocytosis: eliminating toxins or trash from the cell's interior Cells need to get rid of waste and toxins to maintain homeostasis.