Prokaryotic Cells

• What is the main focus of this video?

  Structure of prokaryotic cells
• What types of organisms are included in eukaryotes?

  Animals, plants, and fungi
• Where is the DNA located in eukaryotic cells?

  In a membrane-bound nucleus
• How is DNA organized in eukaryotic cells?

  Coiled around histone proteins
• What is the shape of DNA in eukaryotic cells?

  Linear with free ends
• What are some examples of membrane-bound organelles in eukaryotic cells?

  Mitochondria, Golgi apparatus, endoplasmic reticulum
• What type of cells are bacteria classified as?

  Prokaryotic cells
• How do prokaryotic cells compare in size to eukaryotic cells?

  Prokaryotic cells are much smaller
• Where is the DNA found in prokaryotic cells?

  In the cytoplasm
• How is DNA arranged in prokaryotic cells?

  In a circular chromosome
• What are plasmids?

  Small loops of DNA in bacteria
• What is the significance of plasmids in bacteria?

  They can confer antibiotic resistance
• Do eukaryotic cells contain plasmids?

  No, they do not
• What is the size of ribosomes in prokaryotic cells?

  70s
• How do prokaryotic ribosomes differ from eukaryotic ribosomes?

  Prokaryotic ribosomes are smaller
• What is the composition of the bacterial cell wall?

  Made from peptidoglycan
• What is peptidoglycan?

  A polymer of peptides and polysaccharides
• What role does the bacterial cell wall play?

  Maintains cell structure and prevents bursting
• What is a slime capsule in bacteria?

  A protective layer outside the cell wall
• How does the slime capsule help bacteria?

  Protects from phagocytosis by white blood cells
• What is a flagellum?

  A structure that helps bacteria move
• How does the prokaryotic flagellum differ from the eukaryotic flagellum?

  It has a different structure
• What are pili in bacteria?

  Fine protein strands on the surface
• What is the function of pili?

  Helps bacteria attach to surfaces
• What can happen when two bacteria are attached via pili?

  DNA can be transferred between them
• What do bacteria contain for nutrient storage?

  Lipid droplets and glycogen granules
• What are mesosomes in prokaryotic cells?

  In-foldings in the cell membrane
• What was the initial belief about the function of mesosomes?

  They played a role in respiration
• What do scientists currently believe about mesosomes?

  They are artifacts from preparation
• What are the key structural differences between prokaryotic and eukaryotic cells?

  • Prokaryotic cells are smaller
  • Prokaryotic cells lack membrane-bound organelles
  • Prokaryotic DNA is circular, not linear
  • Prokaryotic ribosomes are smaller (70s vs 80s)
  • Prokaryotic cells have a cell wall made of peptidoglycan
• What are the main functions of the structures found in prokaryotic cells?

  • Ribosomes: Protein synthesis
  • Cell wall: Maintains structure
  • Slime capsule: Protects from phagocytosis
  • Flagellum: Movement
  • Pili: Attachment and DNA transfer
  • Lipid droplets and glycogen granules: Nutrient storage