Methods of studying cells

• What is the formula for magnification?


  Magnification = Image size / Actual size
• If an actual object is 5 µm and the image size is 5 cm, what is the magnification?

  10000x magnification
• What does resolution refer to in microscopy?

  It is the minimum distance between two objects that can be distinguished as separate.
• What is the optimal light wavelength for microscopy?

  Near of light is induced to obtain the image.
• What is a risk associated with using wavelengths below 0.15 µm?

  It cannot be repeated reliably.
• How does higher magnification affect resolution?

  Higher magnification requires sufficient light for resolution and can lead to overlapping images.
• What is the minimum distance for resolution in microscopy?

  0.2 µm
• What is the purpose of staining in microscopy?

  Staining enhances the visibility of structures that are difficult to discern.
• Why must specimens be thin for microscopy?

  Thinner specimens allow for better penetration of the imaging beam.
• What is the first step in the cell fractionation process?

  Homogenization of the cells.
• What happens during ultracentrifugation in cell fractionation?

  Cell components are separated based on their density.
• What are the two stages of cell fractionation?

  1. Homogenization

  • Cells are broken down using a homogenizer.

  1. Ultracentrifugation

  • Components are separated based on density.
• What is the role of a buffer in cell fractionation?

  A buffer maintains the fluidity of the solution during the process.
• What types of organelles can be separated during cell fractionation?

  Nucleus, chloroplasts, mitochondria, lysosomes, ribosomes.
• Why is it important to slice specimens thinly in microscopy?

  Thin slices ensure that the imaging beam can penetrate effectively.
• What is the smallest unit of measurement in microscopy?

  Nanometer
• What is the process of measuring the position of varying agents on a curve in a lab setting?

  • Use a marker to create a position/time graph.
  • Employ gradients made of salt for evidence.
  • Observe gradients on agar plates for gene presentation.
• What is the first step in preparing a sample for migration analysis?

  Cut many fragments and generate a suitable buffering sample.
• What is the purpose of using a gradient in migration analysis?

  A gradient helps to create a preferable difference for observing migration.
• How do you measure the mobility of genes on an agarose film?

  By observing the side of the agarose film after applying the sample.
• What is the significance of using a salt solution in cell fractionation?

  It helps to lyophilize and separate cell components effectively.
• What happens to cells during homogenization?

  Cells are broken down into smaller components.
• How does the presence of chlorine affect the centrifugation process?

  Chlorine helps to separate the components based on density.
• What is the relationship between density and the separation of organelles?

  The less dense the organelle, the larger the liquid needed to suspend it.
• What are the three main types of microscopes?

  Optical light microscope, electron microscope, and optical microscopes
• What is the maximum resolution of optical microscopes?

  Approximately 2000x with a resolution limit of 0.2μm
• What limits the resolution of optical microscopes?

  The wavelength of the illumination
• What is the maximum magnification of optical microscopes?

  Approximately x400 magnification
• What is the purpose of using stains in microscopy?

  To help select and enhance differences in the specimen
• What is a characteristic of lip microscopes?

  They are largely opaque due to strong light and weak image results
• What is the method to adjust focus on a microscope?

  By moving the objective lens, typically requiring more than 2 turns for full magnification
• What are the steps to prepare a dry mount slide?

  1. Place the specimen in the middle of a clean slide.
  2. Place a cover slip on the specimen using a spatula.
• What are the steps to prepare a wet mount slide?

  1. Using a pipette, place a drop of water on the middle of a clean slide.
  2. Place the specimen in the water drop.
  3. Place the cover slip on very slowly.
  4. Place the slide on the stage.
• What is the definition of an object in microscopy?

  An object is the specimen that you put under the microscope.
• What is the definition of an image in microscopy?

  An image is what you observe when looking down the microscope.
• How can magnification be calculated?

  Magnification can be calculated using the formula: Image size / Actual size.
• What happens when you magnify a pre-magnified image?

  It does not give a good image and results in a larger blurred image.
• What is likely the cause if you only get a larger blur when observing a specimen?

  It is likely due to using phase-contrast microscopy, which changes light intensity.
• What does magnification indicate in microscopy?

  Magnification indicates the number of times larger the image is compared to the object.
• What is the minimum distance between two objects to be distinguished as separate objects called?

  It is called the resolution.