Cell Structure

• It is the basic structural and functional units of organisms that perform all life processes.

  Cells
• He made a simple, single-lens microscope.

  Anton van Leeuwenhoek
• Robert Hooke discovered and coined the term “cell”.
• What are the components of the Cell Theory?

  1. All living organisms are composed of cells. 2. The cell is the basic unit of life. 3. Cells arise from pre-existing cells.
• What are the two basic cell types?

  Prokaryotic and Eukaryotic cells
• These cells have false nucleus and does not possess membrane-bound organelles.

  Prokaryotic Cells
• These cells possess true nucleus and has membrane-bound organelles such as the ER and Golgi Apparatus.

  Eukaryotic Cells
• Unicellular organisms


  Prokaryotes
• Multicellular organisms


  Eukaryotes
• What is the method of reproduction among prokaryotic cells?


  Binary fission
• What is the method of reproduction among eukaryotic organisms?

  Sexually and Asexually by mitosis and meiosis
• These are the basic cell parts that perform the physiological activities of the cell.

  Organelles
• It encloses the cytoplasm and forms the boundary between inside the cell and material outside it.

  Cell Membrane
• Cell membranes are selectively permeable.
• What does it mean when cell membranes are selectively permeable?


  They allow some substances to pass into or out of the cells.
• Phospholipid Bilayer is a thin polar membrane made of two layers of lipid molecules.
• What is the purpose of the phospholipid bilayer?

  It serves as a lipid barrier between the inside and outside of the cell.
• The phosphate-containing ends of the phospholipids are hydrophilic.
• The fatty acid ends of the phospholipids are hydrophobic.
• The cytoplasm is the semifluid substance of a cell that fills each cell and is enclosed by the cell membrane.
• What is the intracellular fluid present within the cytoplasm?

  Cytosol
• The Endoplasmic Reticulum is a series of membranes forming sacs and tubules that extends from the outer nuclear membrane into the cytoplasm.
• Endoplasmic Reticulum


  A series of membranes forming sacs and tubules that extends from the outer nuclear membrane into the cytoplasm
• Endoplasmic Reticulum


  • Dubbed as the Circulatory System of the Cell
  • It is the cell's internal transport system
  • The ER allows molecules in the cell to move from one part to another
• Rough Endoplasmic Reticulum (rER)

  • rER has ribosomes attached to it
  • Site of protein synthetization for export/transport from the cell

  
• Smooth Endoplasmic Reticulum (sER)

  • sER has no ribosomes attached to it
  • It is a site lipid synthesis and participates in detoxification of chemical within cells
  • It transports other materials other than protein
• Ribosomes


  • Most common organelles in almost all cells
  • It is not surrounded by a membrane
• Protein Micromachines


  The organelles where proteins are produced (synthesized)

  
• Polysome/Polyribosomes


  A cluster of ribosomes linked together by a molecule of messenger RNA and forming the site of protein synthesis

  
• Free Ribosomes


  • Ribosomes that are not attached to any other organelles
  • Size: 70s
  • Found in prokaryotes
• Attached Ribosomes

  • Lines the membranes of endoplasmic reticulum
  • Size: 80s
  • Found in eukaryotes

  
• Mitochondria


  Large organelles second to nucleus and chloroplasts
• ATP Manufacturer

  • Major sites of adenosine triphosphate (ATP) production within cells
  • Metabolizes carbohydrates and fatty acids to generate energy
• Aerobic Respiration

  Mitochondria carry out aerobic respiration, a series of chemical reaction that require O2 to break down food molecules to produce ATP

  
• Semi-autonomous organelles


  It has its own DNA, so it can reproduce itself by dividing
• Double-membrane organelles

  • It has inner and out membranes separated by a space
  • The outer membrane has a smooth contour, but the inner membranes have numerous folds, called cristae, which project like shelves into the interior of the mitochondria
• Golgi Apparatus/Golgi Complex/Golgi Body


  Consists of closely packed stacks of curved, membrane-bound sacs
• Transport Agent


  Involved in the distribution of lipids around the cell
• Protein Collector & Dispatcher

  Protein synthesized in the ER are packaged into membrane sacs called secretory vesicles and fuse with the Golgi body for secretion via exocytosis

  
• Lysosome Builder

  Lysosomes are vesicles with protein enzymes pinched of by Golgi body to the cytoplasm