1.3 Eukaryotic and prokaryotic cells

• How do the sizes of bacteria compare to other cells in humans and plants?

  Bacteria are vastly smaller than other cells in humans and plants.
• What is the purpose of using orders of magnitude?

  Orders of magnitude are used to make approximate comparisons between numbers or sizes.
• If a number is around 10 times bigger than another, how many orders of magnitude is it bigger?

  It is one order of magnitude bigger.
• How can you determine the order of magnitude when comparing two numbers?

  If the bigger number divided by the smaller number is less than 10, they are the same order of magnitude.
• What is an example of comparing the sizes of a small animal cell and a large plant cell?

  A small animal cell is around $10 \mu m$ and a large plant cell is around $100 \mu m$.
• What does it mean when a large plant cell is described as being an order of magnitude bigger than a small animal cell?

  It means the large plant cell is approximately 10 times bigger than the small animal cell.
• What are the key similarities and differences between animal and plant cells?

  • Similarities:
  • Both have a cell membrane and cytoplasm.
  • Both contain genetic material.

  
  

  • Differences:
  • Plant cells have a cell wall; animal cells do not.
  • Plant cells contain chloroplasts; animal cells do not.
• What are the main characteristics of eukaryotic cells?

  • Have a cell membrane
  • Contain cytoplasm
  • Genetic material enclosed in a nucleus
• What are the main characteristics of prokaryotic cells?

  • Consist of cytoplasm and a cell membrane
  • Not surrounded by a cell wall
  • Genetic material is not in a distinct nucleus, may form a single DNA loop
  • May contain plasmids
• What type of cells are bacteria classified as?

  Bacteria are all prokaryotes.