Cell Structure

• What are all living organisms made of?

  Cells
• What type of cells are humans made up of?

  Eukaryotic cells
• What do all eukaryotic cells contain?

  Nucleus and membrane-bound organelles
• How can a more detailed structure of cells be obtained?

  Using a microscope
• What is the ultrastructure of eukaryotic cells?

  • Nucleus: double membrane, pores, chromatin, nucleolus
  • Rough endoplasmic reticulum: flattened sacs, ribosomes, protein processing
  • Smooth endoplasmic reticulum: membrane-bound sacs, lipid production
  • Golgi apparatus: fluid-filled sacs, protein and lipid packaging
  • Mitochondria: oval-shaped, double membrane, cristae, matrix
  • Centrioles: hollow cylinders, microtubules, cell division
  • Ribosomes: two subunits, protein production
  • Lysosome: vesicle with digestive enzymes
  • Cytoskeleton: mechanical strength, transport, cell movement
• What surrounds the nucleus of eukaryotic cells?

  A double membrane called the envelope
• What is the function of the nucleolus?

  Site of ribosome production
• What is the structure of rough endoplasmic reticulum (RER)?

  Flattened sacs with ribosomes on the surface
• What does the rough endoplasmic reticulum do?

  Folds and processes proteins made on ribosomes
• What is the smooth endoplasmic reticulum (SER) responsible for?

  Producing and processing lipids
• What is the Golgi apparatus composed of?

  Fluid-filled, flattened, and curved sacs
• What are the functions of the Golgi apparatus?

  Processes and packages proteins and lipids
• What do mitochondria contain that is essential for respiration?

  Enzymes in the matrix
• What is the shape of mitochondria?

  Usually oval-shaped
• What are centrioles involved in?

  Cell division
• What are ribosomes composed of?

  Two subunits
• What do lysosomes contain?

  Digestive enzymes
• What role does the cytoskeleton play in the cell?

  Provides mechanical strength and aids transport
• What is the process of protein transport in eukaryotic cells?

  1. Proteins produced on ribosomes
  2. Folded and processed in RER
  3. Transported to Golgi apparatus in vesicles
  4. Modified in Golgi apparatus
  5. Packaged into vesicles for transport
  6. Some proteins leave the cell by exocytosis
• What is the cell wall of prokaryotic cells made of?

  Peptidoglycan
• What is the function of the capsule in prokaryotic cells?

  Helps retain moisture and adhere to surfaces
• What is a plasmid?

  Circular piece of DNA
• What is the function of the flagellum in prokaryotic cells?

  Rotates to move the cell
• What are pili in prokaryotic cells?

  Hair-like structures that attach to cells

  
• What is the role of ribosomes in prokaryotic cells?

  Site of protein production