biology b1

• What type of cell has no nucleus?

  Prokaryotic cell
• What organisms are classified as prokaryotes?

  Bacteria
• What type of cell contains a nucleus?

  Eukaryotic cell
• Which organisms are classified as eukaryotes?

  Protists, fungi, plants, and animals
• Why do cells require a microscope to visualize them?

  Cells are very small
• What is the purpose of lenses in microscopes?

  To magnify the image
• What is the formula for calculating magnification?

  Magnification = size of image / real size
• What are the main components of a microscope?

  • Eyepiece
  • Objective lenses
  • Stage clip
  • Condenser
  • Coarse focus
  • Fine focus
  • Arm
  • Stage
  • Mirror
• What is the purpose of stains in microscopy?

  To add contrast to cells
• What is active transport in cells?

  Pumping particles against the concentration gradient
• What is a concentration gradient?

  The difference between two concentrations
• What is diffusion?

  Random movement of particles from high to low concentration
• What is a eukaryotic cell?

  A cell with a nucleus and organelles
• What are gametes?

  Haploid cells produced by meiosis
• What does hypertonic mean?

  Higher solute concentration outside the cell
• What does hypotonic mean?

  Lower solute concentration outside the cell
• What does isotonic mean?

  Equal solute concentration inside and outside
• What are organelles?

  Small structures inside cells with specific functions
• What is osmosis?

  Movement of solvent molecules across a membrane
• What is a partially permeable membrane?

  A membrane allowing certain particles to pass
• What is plasmolysis?

  Cell membrane pulls away from cell wall
• What is resolution in microscopy?

  Smallest distance between two visible points
• What is a specialized cell?

  A cell adapted for a specific function
• What is the method for preparing a microscope specimen?

  Swab mouth, mix with water, place on slide
• What is the total magnification formula?

  Eyepiece magnification × objective magnification
• What are the three main processes for substance movement in cells?

  1. Diffusion
  2. Osmosis
  3. Active Transport
• What is the effect of a higher concentration gradient on diffusion?

  Increases the rate of diffusion
• What is the relationship between surface area and diffusion rate?

  Larger surface area increases diffusion rate
• What is the definition of active transport?

  Movement against the concentration gradient using energy
• What is the significance of surface area to volume ratio in organisms?

  Larger organisms have smaller surface area to volume ratio
• What is the method for calculating surface area to volume ratio?

  Surface area divided by volume
• What is the method for conducting an osmosis experiment with potato cylinders?

  1. Prepare sucrose solutions.
  2. Set up boiling tubes with solutions.
  3. Label each tube with concentration.
  4. Weigh potato cylinders before and after.
  5. Calculate percentage change.
• What happens to the surface area to volume ratio as organisms increase in size?

  The ratio decreases as size increases
• What mechanisms do large organisms use to increase surface area?

  They use exchange surfaces or shape changes
• What is the method for investigating the effect of sucrose concentration on potato cylinders?

  • Prepare sucrose solutions (0.2 to 1.0 mol dm³)
  • Set up boiling tubes with solutions and distilled water
  • Label each tube with concentration
  • Weigh potato cylinders before and after
  • Calculate percentage change in mass
  • Repeat for several cylinders to ensure repeatability
• What happens to potato in a sugar solution?

  It loses water and mass
• What is the definition of an active site in enzymes?

  Space where substrate fits in enzyme
• What is a catalyst?

  A substance that speeds up reactions
• What does it mean when an enzyme is denatured?

  Active site shape changes, substrate won't fit
• What is the lock and key model in enzymes?

  Describes enzyme-substrate fitting mechanism