Cell Biology

• What is the structure inside all cells called?

  Sub-cellular structures
• What is the function of the nucleus in an animal cell?

  It controls the activities of the cell
• Where do most chemical reactions take place in an animal cell?

  In the cytoplasm
• What is the role of the cell membrane?

  It controls substance passage in and out
• Where does aerobic respiration occur in an animal cell?

  In the mitochondria
• What is synthesized in ribosomes?

  Proteins
• How do plant cells differ from animal cells?

  • Plant cells have a cell wall made of cellulose
  • They contain a permanent vacuole filled with cell sap
  • Some plant cells have chloroplasts for photosynthesis
• What is the function of the cell wall in plant cells?

  It strengthens the cell
• What is contained in a permanent vacuole?

  Cell sap
• Why do some plant cells contain chloroplasts?

  To absorb light for photosynthesis
• What is the main difference between prokaryotic and eukaryotic cells?

  Prokaryotic cells lack a nucleus
• What type of cells are bacterial cells?

  Prokaryotic cells
• What are the key differences between prokaryotic and eukaryotic cells?

  • Prokaryotic cells are smaller
  • Genetic material is not enclosed in a nucleus
  • They have a single DNA loop and plasmids
  • They lack mitochondria and chloroplasts
• What shapes can bacterial cells have?

  Round, rod-shaped, or spiral
• What takes over the roles of mitochondria and chloroplasts in bacterial cells?

  The cytoplasm
• What are plasmids in bacterial cells?

  Circles of DNA that can transfer genes
• What provides structural support to bacteria?

  The cell wall
• What is chromosomal DNA in bacteria?

  One circular chromosome not in a nucleus
• What are flagella in bacterial cells?

  Tail-like structures for movement
• Why are prokaryotic cells considered simpler than eukaryotic cells?

  • They have fewer organelles
  • They lack a nucleus
  • They have a simpler structure overall
• What is the typical diameter of a plant cell?

  About 0.1 mm
• What is the typical diameter of an animal cell?

  About 0.02 mm
• How long are prokaryotic cells typically?

  About 0.002 mm
• What is resolution in microscopy?

  The ability to see separate objects clearly
• What did the light microscope allow scientists to see?

  Plant, animal, and bacterial cells
• What is the advantage of an electron microscope?

  It provides much better resolution
• What can be studied in finer detail using an electron microscope?

  Structures inside mitochondria and chloroplasts
• What is the procedure for using a light microscope to observe cells?

  1. Place tissue on a slide
  2. Add a suitable stain
  3. Lower a coverslip
  4. Focus using low power
  5. Change to high power and refocus
  6. Draw and label observed cells
  7. Add a scale line
• What is the size of a typical plant cell in micrometres?

  About 100 µm
• What is the size of a typical animal cell in micrometres?

  About 20 µm
• What is the size of a typical bacterium in micrometres?

  About 2 µm
• What is magnification in microscopy?

  How many times larger the image is
• What is binary fission?

  A type of simple cell division in bacteria
• How frequently can bacteria multiply under optimal conditions?

  Every 20 minutes
• What is a culture in microbiology?

  Growing bacteria in nutrient broth or agar
• What is the purpose of sterilizing Petri dishes and agar?

  To kill unwanted microorganisms
• What is aseptic technique?

  A method to prevent culture contamination
• At what maximum temperature should cultures be incubated in schools?

  25°C
• Why should cultures be stored upside down?

  To prevent condensation on agar surface
• What is the mean division time for bacteria?

  Approximately every 20 minutes