Cell organisation

• What is the structure of the plasma membrane?

  Phospholipid bilayer
• What is the primary function of mitochondria?

  They generate ATP
• What do lysosomes contain?

  Hydrolytic enzymes
• What is found within the nucleus?

  The nucleolus
• What bounds the nucleus?

  The nuclear envelope
• What distinguishes rough endoplasmic reticulum (RER) from smooth endoplasmic reticulum (SER)?

  RER is studded with ribosomes
• What is the function of the smooth endoplasmic reticulum (SER)?

  Site of lipid synthesis and detoxification
• What does the Golgi complex do?

  Processes and sorts secreted proteins
• What are secretory vesicles packed with?

  Secreted proteins
• What is the function of peroxisomes?

  Degrade fatty acids and detoxify compounds
• What role does the cytoskeleton play in the cell?

  Provides support and organizes organelles
• What is the cell wall made of?

  Tough, rigid layer
• What is the function of the central vacuole in plant cells?

  Maintains turgor pressure
• What is the primary function of chloroplasts?

  Sites of photosynthesis
• What are plasmodesmata?

  Tube-like connections between plant cells
• Label cell components based on image

  
• Lysosomes


  Membrane-bound organelles found in the cells of most eukaryotes, containing hydrolytic enzymes that break down molecules using water.
• Hydrolytic Enzymes


  Enzymes that break down molecules using water, responsible for degrading proteins, carbohydrates, and fats, and recycling cellular waste and debris.
• Smooth Endoplasmic Reticulum (SER)


  A type of organelle involved in lipid synthesis and detoxification
• Lipid Synthesis


  The process of creating lipids, such as phospholipids and cholesterol, in the Smooth Endoplasmic Reticulum (SER)
• Detoxification


  The process of breaking down and removing toxic substances, such as xenobiotics and metabolic waste, in the Smooth Endoplasmic Reticulum (SER)
• Protein Synthesis


  The process of creating proteins through translation, using messenger RNA (mRNA) as a template, in the Rough Endoplasmic Reticulum (RER)
• What does the plasma membrane do?

  Separates cell from external environment
• How thick is the plasma membrane?

  Approx. 3.5 nm thick
• What is the function of the plasma membrane?

  Controls entry and exit of macromolecules
• What are the main components of the plasma membrane?

  Composed of lipids, proteins, and carbohydrates
• What surrounds the mitochondria?

  Bounded by a double membrane
• What is the primary function of mitochondria?

  Generate ATP by oxidation of glucose and fatty acids
• What are lysosomes filled with?

  ~40 hydrolytic enzymes
• What is the function of lysosomes?

  Degrade material internalized by the cell
• What pH is maintained in the lysosomal lumen?

  Acidic lumen (pH 5)
• How is the acidic lumen of lysosomes maintained?

  By membrane pumps that import H+ from cytosol
• What are the major roles of lysosomes in immune cells?

  1. Help degrade phagocytosed pathogens (e.g. bacteria)
  2. Process foreign antigen for presentation to T cells
• What surrounds the nucleus?

  The nuclear envelope
• What is found inside the nucleus?

  Filled with chromatin (DNA and protein)
• What is synthesized in the nucleus?

  Site of mRNA and tRNA synthesis
• What is the structure of the nuclear envelope?

  A double membrane surrounding the nucleus
• What is the relationship between the outer nuclear membrane and the rough ER?

  The outer membrane is continuous with the rough ER
• What is the function of the nucleolus?

  Where most of the cell’s ribosomal RNA is made
• What are the functions of the endoplasmic reticulum?

  Lipid synthesis & detoxification of compounds