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• Prokaryotic Cell

  These are unicellular organisms that do not develop or differentiate into multicellular forms. They are identical and capable of independent existence.

  They lack a nucleus and

  membranous organelles.

  Include all bacteria and archaea (archaebacteria).
• Eukaryotic Cell

  These cells contain a nucleus and membrane-bound compartments, called organelles, in which specific metabolic activities take place.

  Include fungi, animals, and plants as well as some unicellular organisms.
• The cell is the basic unit of life. It contains all the information needed to carry out its functions and can be considered an individual living thing. The cell is also the smallest unit of structure and function in living things.
• Cell membrane – It controls what gets in and out of the cell
• Cytoplasm – It is the living substance of the cell
•  Cytosol -It is the fluid portion of the cell.
• Mitochondrion – It is the powerhouse of the cell
• Endoplasmic Reticulum – Responsible for intracellular transport
• Soft ER- sacrifice ribosomes
• Rough ER-
• ROUGH ER- ORIGIN IN NUCLEUS
• Golgi body – Modifies, packages and transports proteins
• Lysosome - SUICIDE BAG OF CELL
• Vacuole - A membrane bound sac found within plant cells which stores water, waste products or pigments.
• Plant Cell Wall - The outermost layer of the cell wall made up of cellulose fibers.
• Nucleus - The control center of the cell containing genetic material (DNA).
• Cell Membrane - The selectively permeable barrier surrounding the cytoplasm of a cell.
• Endoplasmic Reticulum - A network of tubules and sacs involved in protein synthesis and transport.
• Nucleus - A rounded structure at the center of the cell that controls the metabolic activities. It contains the DNA
• Ribosomes - Small structures that are responsible for protein synthesis.
• Plant Cell vs. Animal Cell

   

  · Plant and animal cells are very similar because they are both eukaryotic cells.

  · Plant cells are usually larger than animal cells.

  · They contain structures that are absent in a typical animal cell, such as chloroplasts, plastids cell walls and large vacuoles.

  · Organelles are found in an animal cell that are absent in plant cells.

  · These include centrioles, lysosomes (rarely seen in plant cells), microvilli, cilia, and filaments.
• The cell membrane serves as a clear boundary between the cell’s internal and external environment.

  It is called plasma membrane or plasma lemma.

  It is semi-permeable with a framework of fat-based molecules called phospholipids, which prevent hydrophilic substances from entering or escaping the cell.

  All membranes are phospholipid bilayers with embedded proteins.
• Phosphate head

   

  Polar

  Hydrophilic
• Fatty Acid Tail

   

  Non-polar

  Hydrophobic
• Proteins

   

  Transmembrane Proteins

  Integral Proteins

  Peripheral Proteins
• FUNCTION OF THE CELL MEMBRANE

  Delimits the cell from its surroundings.

  Controls what gets in and out of the cell.

  Provides attachment for the skeleton of the cell.

  Receives and sends out stimuli.

  Provides binding sites and receptors for enzymes and other substances.

  Allows cell-to-cell recognition.

  Forms specialized junctions with cell membranes of adjacent cells.
• Active

  Requires energy

  Goes against the concentration gradient
• Passive

  Does not require energy

  Goes with the concentration gradient

   
• SIMPLE DIFFUSION

  · Diffusion is the random movement of molecules from an area of high concentration to low concentration

  · Requires NO energy
• Oxygen – Nonpolar so diffuses very quickly. Carbon dioxide – Polar but very small so diffuses quickly.

  Water – Polar but also very small so diffuses quickly.
• Osmosis is the diffusion of water across a membrane.

  Moves from HIGH water concentration to LOW water concentration.
• Isotonic-A solution whose solute concentration is the same as the solute concentration inside the cell.
• Hypotonic-A solution whose solute concentration is lower than the solute concentration inside a cell.
• Hypertonic-A solution whose solute concentration is higher than the solute concentration inside a cell.
• Channel proteins are embedded in the cell membrane & have a pore for materials to cross.
• Carrier proteins can change shape to move material from one side of the membrane to the other
• TYPES OF TRANSPORT PROTEINS: Carrier proteins and Channel proteins
• CELLS IN SOLUTIONS:Isotonic, Hypotonic, Hypertonic
• MOLECULES THAT DIFFUSE THROUGH CELL MEMBRANES:Oxygen, arbon dioxide, WATER