B1: Cell Biology

• What is the purpose of the cell membrane in a plant cell?

  Controls what goes in and out
• What is the function of the cell wall in a plant cell?

  Provides structure
• Where do most cellular reactions take place in a plant cell?

  In the cytoplasm
• What is the role of ribosomes in a cell?

  Responsible for protein synthesis
• What do chloroplasts do in a plant cell?

  Involved in photosynthesis
• What is the function of mitochondria in a cell?

  Produce energy
• What is the nucleus responsible for in a cell?

  Holds DNA and controls the cell
• What features do plant cells have that animal cells do not?

  Cell wall, vacuole, chloroplasts
• What is unique about bacterial cells compared to plant and animal cells?

  DNA is not in a nucleus
• What is differentiation in cells?

  Process where cells specialize for functions
• What is the role of villi in the gut?

  Increase surface area for absorption
• How do neurons differ from muscle cells?

  Neurons have long axons for signaling
• What is the basic structure of a cell?

  Cell membrane, cytoplasm, nucleus
• What is the formula for calculating magnification?

  Magnification = image height / object height
• What is DNA made of?

  Deoxyribonucleic acid with A, T, C, G
• What is the structure of DNA?

  Twists into a double helix
• What happens during mitosis?

  One parent cell divides into two identical cells
• What is the first step in mitosis?

  DNA condenses into chromosomes
• What are stem cells?

  Cells that can differentiate into any type
• How can stem cells be used in medicine?

  To grow new cells or organs
• What is the controversy surrounding stem cells?

  Creation and destruction of human embryos
• What is diffusion?

  Movement from high to low concentration
• How does diffusion occur in the lungs?

  Oxygen moves into blood, CO2 out
• What is osmosis?

  Movement of water through a membrane
• Where does osmosis occur in plants?

  In root hair cells for water uptake
• What is active transport?

  Movement from low to high concentration
• How does active transport occur in the gut?

  Glucose is absorbed against the gradient
• What should you be able to do by the end of the video?

  Describe how to use an optical microscope
• Why is it important to learn the details of using an optical microscope?

  It could come up in a six mark essay
• What is the main part of the optical microscope where the slide is placed?

  The stage
• What is the function of the clips on the stage?

  To hold the slide in place
• What is located below the stage of an optical microscope?

  A lamp or a mirror
• How does a mirror function in some optical microscopes?

  It reflects light up through the slide
• What are the lenses above the stage called?

  Objective lenses
• How many objective lenses do most microscopes have?

  Three different objective lenses
• What are the typical magnifications of the objective lenses?

  Four, ten, and forty times
• What is the magnification of the eyepiece lens?

  Ten times
• What are the two focusing dials on the microscope?

  Coarse and fine focusing dials
• What is the first step to view a prepared slide using an optical microscope?

  Place the slide onto the stage
• What should you select first when using an optical microscope?

  The lowest power objective lens