cards

• What is diffusion?


  The natural movement of particles
• How does diffusion occur?


  From high concentration to low concentration
• What is a concentration gradient?


  A change in concentration from one region to another
• What does the surface area to volume ratio indicate?


  Comparison of surface area to volume of an organism
• Why is a smaller surface area to volume ratio significant?


  It makes substance exchange harder and slower
• What is osmosis?


  Movement of water through a partially permeable membrane
• What direction does water move during osmosis?


  Into a solution with lower water concentration
• What is active transport?


  Movement of substances against a concentration gradient
• What does active transport require?


  Energy to move substances
• What are the key differences between diffusion, osmosis, and active transport?


  • Diffusion:
  • Allows molecules to move
  • Movement is down a concentration gradient
  • Does not require energy

  
  

  • Osmosis:
  • Always involves the movement of water
  • Movement is down a concentration gradient
  • Does not require energy

  
  

  • Active Transport:
  • Allows molecules to move
  • Movement is against a concentration gradient
  • Requires energy from respiration
• What are chromosomes made from?


  DNA
• What do nucleic acid molecules contain?


  Genetic information
• What is a gene?


  Part of a chromosome coding for a protein
• What is the cell cycle?


  The series of growth and division events in a cell's life
• What is mitosis?


  Cell division forming two daughter cells
• What are stem cells?


  Cells that have not undergone differentiation
• What are embryonic stem cells capable of?


  Differentiating into any type of cell
• What are adult stem cells limited to?


  Differentiating into limited types of cells
• What is therapeutic cloning?


  Cloning to treat diseases without offspring
• What are meristems?


  Areas of cells in plants that can divide
• What is resolution in microscopy?


  The smallest distance two objects can be seen apart
• What does an electron microscope do?


  Fires electrons to obtain high resolution images
• What is magnification?


  How many times larger an image is than the real object
• Why is high resolution important in microscopy?


  It allows for clearer distinction between objects
• What is the diameter of a typical plant cell?


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


  0.02 mm
• How long are prokaryotic cells typically?


  0.002 mm
• What are the units of measurement for cell size?


  • Centimetre (cm)
  • Millimetre (mm)
  • Micrometre (µm)
  • Nanometre (nm)
• How do you calculate magnification?


  • Magnification = size of image / size of real object
• What is the control center of the cell called?


  Nucleus
• Where do chemical reactions take place in a cell?


  Cytoplasm
• What is the function of the cell membrane?


  Controls what enters and leaves the cell
• What structures in the cytoplasm produce energy?


  Mitochondria
• Where does protein synthesis occur in the cell?


  Ribosomes
• What is the function of the cell wall?


  Supports and protects the cell
• What carbohydrate makes up the cell wall of plants?


  Cellulose
• What is the function of a vacuole?


  Storage and support
• What structure contains chlorophyll in plants?


  Chloroplast
• What are prokaryotic organisms characterized by?


  No nucleus or organelles
• What defines eukaryotic cells?


  Presence of a nucleus