Cell division

• What is the process called when cells become specialized?

  Differentiation
• What adaptations do sperm cells have for their function?

  • Long tail for swimming
  • Streamlined shape
  • Packed with mitochondria for energy
  • Contains enzymes to digest the ovum's outer layer
• What is the primary function of sperm cells?

  To join with an ovum during fertilization
• How do sperm cells contain genetic information?

  They contain genetic information in the nucleus
• What are the key features of nerve cells?

  • Long axon for transmitting impulses
  • Myelin sheath for insulation and speed
  • Synapses for passing impulses to other nerve cells
  • Dendrites to increase surface area for connections
• What is the main function of nerve cells?

  To send electrical impulses around the body
• What role does myelin play in nerve cells?

  It insulates the axon and speeds up impulse transmission
• What adaptations do muscle cells have for their function?

  • Contain protein fibers that can change length
  • Packed with mitochondria for energy
  • Work together to form muscle tissue
• What is the key feature of muscle cells?

  They can contract, or get shorter
• What happens to the protein fibers in muscle cells when they contract?

  They shorten, decreasing the length of the cell
• What do muscle cells require for contraction?

  Energy provided by mitochondria
• How do muscle cells work together?

  • They form muscle tissue
  • Collaborate to enable movement
  • Function collectively for contraction
• What are three key structures found in a general plant cell?

  Chloroplasts, cellulose cell wall, and permanent vacuole
• How do root hair cells adapt to their function?

  • Increase surface area for water absorption
  • Lack chloroplasts since they are underground
• What is the function of root hair cells?

  To absorb water and dissolved minerals
• Why do root hair cells not contain chloroplasts?

  Because they are underground and do not carry out photosynthesis
• What are the key features of xylem cells?

  • Thick walls containing lignin for support
  • End walls have broken down to form long tubes
  • No nucleus, cytoplasm, vacuole, or chloroplasts
• What do xylem cells transport?

  Water and dissolved minerals
• How does lignin benefit xylem cells?

  It provides structural support to the plant
• What happens to the internal structures of xylem cells?

  They have no internal structures to facilitate water flow
• What are the key features of phloem cells?

  • Consist of phloem vessel cells and companion cells
  • Phloem vessel cells have no nucleus and limited cytoplasm
  • End walls have sieve plates for sugar movement
• What do phloem cells transport?

  Dissolved sugars
• What is the role of companion cells in phloem?

  They provide energy to phloem vessel cells
• Why do phloem vessel cells have limited cytoplasm?

  To allow dissolved sugars to move through the cell interior
• What are sieve plates in phloem cells?

  Pores in the end walls of phloem vessel cells
• What are the differences between xylem and phloem cells?

  • Xylem: transports water and minerals, has thick walls with lignin, no internal structures
  • Phloem: transports sugars, has sieve plates, and companion cells for energy
• What type of organisms are bacteria classified as?

  Bacteria are prokaryotes
• How is the genetic information of bacteria organized?

  The genetic information of bacteria is not enclosed in a nucleus
• What process do bacteria use to multiply?

  Bacteria multiply by simple cell division
• What is binary fission?

  Binary fission is when one bacterial cell splits into two bacterial cells
• How often can bacteria carry out binary fission under ideal conditions?

  Bacteria can carry out binary fission every 20 minutes
• What conditions are necessary for bacteria to multiply rapidly?

  Enough nutrients and suitable temperature
• How do you calculate the number of bacteria after a certain time?

  Use the equation: number of bacteria = $2^n$, where $n$ is the number of rounds of division
• What are the conditions for bacteria to multiply rapidly?

  • Sufficient nutrients
  • Suitable temperature
• What is the process of binary fission in bacteria?

  • One bacterial cell splits into two.
  • Occurs every 20 minutes under ideal conditions.
• How do bacteria reproduce?

  Bacteria reproduce by binary fission
• Under suitable conditions, how often can bacteria double in number?

  Every 20 minutes
• What is a nutrient broth solution used for?

  It contains all the nutrients that bacteria need to grow and divide
• Why does the broth appear cloudy?

  Because it contains a very large number of bacteria
• What is an agar gel plate?

  Agar gel plates contain nutrient broth that has been solidified into a jelly using agar