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Organelles are separate compartments in [[Eukaryotic|eukaryotic]] cells that contain different [[Enzyme|enzymes]] and [[Molecule|molecules]] and have specific roles in maintaining [[Cell|cell]] structure and function <ref>Alberts B, Johnson A, Lewis J, Raff M, Roberts K, Walter P. 2008. Molecular Biology of the Cell. 5th Edition. p695. Garland Science, New York</ref>. Each organelle has its own membrane in the form of a [[Lipid bilayer|lipid bilayer]], this allows [[Compartmentalisation|compartmentalisation and]] segragation of different chemical activites. Different organelles can be seperated by [[Centrifugation|centrifugation]] due to thier varying densities.  
Organelles are separate compartments in [[Eukaryotic|eukaryotic]] cells that contain different [[Enzyme|enzymes]] and [[Molecule|molecules]] and have specific roles in maintaining [[Cell|cell]] structure and function<ref>Alberts B, Johnson A, Lewis J, Raff M, Roberts K, Walter P. 2008. Molecular Biology of the Cell. 5th Edition. p695. Garland Science, New York</ref>. Each organelle has its own membrane in the form of a [[Lipid bilayer|lipid bilayer]], this allows [[Compartmentalisation|compartmentalisation]] and segregation of different chemical activities. Different organelles can be separated by [[Centrifugation|centrifugation]] due to their varying densities.  


=== Eukaryotic Organelles and their Functions:  ===
=== Eukaryotic Organelles and their Functions:  ===


*[[Ribosomes|Ribosomes]] - host sites for protein synthesis: translation of [[MRNA|mRNA]] into [[Proteins|proteins]].
*[[Ribosomes|Ribosomes]] - host sites for protein synthesis: translation of [[MRNA|mRNA]] into [[Proteins|proteins]]&nbsp;(80s)
*[[Nucleus|Nucleus]] - contains chromosomes as a store of genetic information.
*[[Nucleus|Nucleus]] - contains chromosomes as a store of genetic information
*[[Nuclear envelope|Nuclear envelope]] - surrounds the nucleus, allows passage of material into and out of the nucleus. Eg [[MRNA|mRNA]]&nbsp;
*[[Nucleolus|Nucleolus]] - a dense structure located in the nucleus, makes ribosomal subunits
*[[Rough Endoplasmic Reticulum|Rough ER]] (endoplasmic reticulum) - located next to the nucleus, the rough ER has docked ribosomes for protein synthesis.&nbsp;
*[[Nuclear envelope|Nuclear envelope]] - surrounds the nucleus, allows passage of material into and out of the nucleus. E.g. [[MRNA|mRNA]]  
*[[Rough Endoplasmic Reticulum|Rough ER]] (endoplasmic reticulum) - located next to the nucleus, the rough ER has docked ribosomes for protein synthesis
*[[Smooth endoplasmic reticulum|Smooth ER]] - endoplasmic reticulum without docked [[Ribosomes|ribosomes]] - synthesis of lipids and steroids  
*[[Smooth endoplasmic reticulum|Smooth ER]] - endoplasmic reticulum without docked [[Ribosomes|ribosomes]] - synthesis of lipids and steroids  
*[[Lysozyme|Lyso]][[Lysosome|some]]&nbsp;- contain [[Hydrolytic enzyme|hydrolytic enzyme]][[Hydrolytic enzymes|s]] for intracellular degredation
*[[Lysozyme|Lyso]][[Lysosome|some]] - contain [[Hydrolytic enzyme|hydrolytic enzyme]][[Hydrolytic enzymes|s]] for intracellular degradation
*[[Endosomes|Endosomes]] - sort endocytosed materials  
*[[Endosomes|Endosomes]] - sort endocytosed materials
*[[Golgi apparatus|Golgi Body]] - post-transcriptional modification, separation and assortment of newly synthesised proteins  
*[[Golgi apparatus|Golgi Body]] - post-transcriptional modification, separation and assortment of newly synthesised proteins  
*[[Peroxisomes|Peroxisomes]] - contain [[Enzymes|enzymes]] for oxidation of toxins
*[[Peroxisomes|Peroxisomes]] - contain [[Enzymes|enzymes]] for [[Oxidation|oxidation]] of toxins  
*[[Mitochondria|Mitochondria]] - the powerhouse of the cell that plays a key role in aerobic cell respiration<ref>Becker's World of the Cell Hardin, J. et al. (2012) Becker's World of the Cell. 8th ed. San Francisco: Pearson, p.253.</ref>
*[[Cytoskeleton|Cytoskeleton]] - Important role in cell movement and cell division<ref>Becker's World of the Cell Hardin, J. et al. (2012) Becker's World of the Cell. 8th ed. San Francisco: Pearson, p.422.</ref>
*[[Plasma membrane|Plasma membrane]] - controls what enters and leaves the cell
 
=== Prokaryotic Organelles and their Functions:  ===
 
*[[Cell wall|Cell Wall]] - this gives the cell its shape and structure, can anchor the appendages ([[Flagella|flagella]] and pili)
*[[Plasma membrane|Plasma membrane]] - controls what enters and leaves the cell (also present in eukaryotic cells)
*[[Ribosomes|Ribosomes]] - the site of protein synthesis, (70s)
*[[Nucleoid|Nucleoid]] - this is an area in the [[Cytoplasm|cytoplasm]] where strands of [[DNA|DNA are]] found, and it is not a membrane-bound organelle
*[[Pili|Pili]] - these are hair-like projections coming from outside of the cell, this attaches to other cell surfaces
*[[Flagella|Flagella]] - hairlike structures allowing the cell to move by beating in a corkscrew-like motion to nutrients and chemicals<ref>Available: http://quizlet.com/14315658/function-of-organelles-in-both-prokaryotic-and-eukaryotic-cells-flash-cards/. Last accessed 25/11/14</ref>
*[[Mesosomes|Mesosomes]] - These are folded invaginations of the plasma membrane. They can contain various enzymes used in respiration<ref>http://www.ivyroses.com/Biology/Cells/Prokaryotic-Cell-Structure.php</ref>


=== References  ===
=== References  ===


<references /><br>
<references />

Latest revision as of 09:23, 19 November 2018

Organelles are separate compartments in eukaryotic cells that contain different enzymes and molecules and have specific roles in maintaining cell structure and function[1]. Each organelle has its own membrane in the form of a lipid bilayer, this allows compartmentalisation and segregation of different chemical activities. Different organelles can be separated by centrifugation due to their varying densities.

Eukaryotic Organelles and their Functions:

  • Ribosomes - host sites for protein synthesis: translation of mRNA into proteins (80s)
  • Nucleus - contains chromosomes as a store of genetic information
  • Nucleolus - a dense structure located in the nucleus, makes ribosomal subunits
  • Nuclear envelope - surrounds the nucleus, allows passage of material into and out of the nucleus. E.g. mRNA
  • Rough ER (endoplasmic reticulum) - located next to the nucleus, the rough ER has docked ribosomes for protein synthesis
  • Smooth ER - endoplasmic reticulum without docked ribosomes - synthesis of lipids and steroids
  • Lysosome - contain hydrolytic enzymes for intracellular degradation
  • Endosomes - sort endocytosed materials
  • Golgi Body - post-transcriptional modification, separation and assortment of newly synthesised proteins
  • Peroxisomes - contain enzymes for oxidation of toxins
  • Mitochondria - the powerhouse of the cell that plays a key role in aerobic cell respiration[2]
  • Cytoskeleton - Important role in cell movement and cell division[3]
  • Plasma membrane - controls what enters and leaves the cell

Prokaryotic Organelles and their Functions:

  • Cell Wall - this gives the cell its shape and structure, can anchor the appendages (flagella and pili)
  • Plasma membrane - controls what enters and leaves the cell (also present in eukaryotic cells)
  • Ribosomes - the site of protein synthesis, (70s)
  • Nucleoid - this is an area in the cytoplasm where strands of DNA are found, and it is not a membrane-bound organelle
  • Pili - these are hair-like projections coming from outside of the cell, this attaches to other cell surfaces
  • Flagella - hairlike structures allowing the cell to move by beating in a corkscrew-like motion to nutrients and chemicals[4]
  • Mesosomes - These are folded invaginations of the plasma membrane. They can contain various enzymes used in respiration[5]

References

  1. Alberts B, Johnson A, Lewis J, Raff M, Roberts K, Walter P. 2008. Molecular Biology of the Cell. 5th Edition. p695. Garland Science, New York
  2. Becker's World of the Cell Hardin, J. et al. (2012) Becker's World of the Cell. 8th ed. San Francisco: Pearson, p.253.
  3. Becker's World of the Cell Hardin, J. et al. (2012) Becker's World of the Cell. 8th ed. San Francisco: Pearson, p.422.
  4. Available: http://quizlet.com/14315658/function-of-organelles-in-both-prokaryotic-and-eukaryotic-cells-flash-cards/. Last accessed 25/11/14
  5. http://www.ivyroses.com/Biology/Cells/Prokaryotic-Cell-Structure.php