PhBioSci Lab

• What are the two main types of microscopes mentioned?

  • Simple Microscope: Consists of a single lens or lens combination.
  • Compound Microscope: Consists of two simple microscopes used together, also known as the bright field microscope.
• What are the two main parts of a compound microscope?

  Mechanical parts and optical parts
• What are the functions of the mechanical parts of a compound microscope?

  • Provide support to the instrument.
  • Hold the lenses and allow for easy shifting between objectives.
• What is the role of the optical parts in a compound microscope?

  • Direct light waves to the specimen.
  • Produce a clear, magnified image.
• What is the function of the objectives in a compound microscope?

  They are the primary magnifiers focused on the specimen.
• What is the function of the ocular (eyepiece) in a compound microscope?

  It serves as the secondary magnifier close to the eye.
• What are the mechanical parts of a compound microscope?

  1. Draw Tube
  2. Body Tube
  3. Revolving Nosepiece
  4. Dust Shield
  5. Arm (Handle)
  6. Stage
  7. Spring Clips
  8. Sub-Stage
  9. Adjustment Knobs (Coarse and Fine)

  10. Inclination Joint

  11. Pillar

  12. Base
• What is the purpose of the draw tube in a microscope?

  It is a cylindrical metal tube with a movable ocular inserted at the top end.
• What does the body tube do in a microscope?

  It holds the lenses and provides support to the revolving nosepiece.
• What is the function of the revolving nosepiece?

  It holds the objectives and allows for easy shifting between them.
• What is the purpose of the dust shield in a microscope?

  It prevents dust from entering the objectives.
• What is the function of the arm (handle) in a microscope?

  It is used for carrying the microscope and supporting the body tube.
• What is the stage of a microscope?

  It is a flat platform where the glass slide with the specimen is placed.
• What are spring clips used for in a microscope?

  They are used to secure the slide in position.
• What is the sub-stage in a microscope?

  It is located below the stage and contains the diaphragm and the Abbe condenser.
• What are the adjustment knobs in a microscope used for?

  • Coarse Adjustment: Used for scanning or focusing the low power objective.
  • Fine Adjustment: Used for focusing the high power and oil immersion objectives.
• What is the inclination joint in a microscope?

  It allows tilting of the microscope for convenience.
• What is the base of a microscope?

  It is the U-shaped or horse-shaped iron portion on which the microscope rests.
• What are the illuminating parts of a microscope?

  1. Mirror
  2. Iris Diaphragm
  3. Abbe Condenser
• What is the function of the mirror in a microscope?

  It is used to catch and direct light to the object.
• What are the two surfaces of the mirror in a microscope?

  Flat (Plane) Surface and Concave Surface
• When is the flat surface of the mirror used?

  Under natural light.
• When is the concave surface of the mirror used?

  Under artificial light.
• What is the function of the iris diaphragm?

  It regulates the amount of light entering the microscope.
• Where is the Abbe condenser located?

  Below the stage.
• What is the function of the Abbe condenser?

  It concentrates and focuses light from the diaphragm onto the object.
• What are the magnifying parts of a microscope?

  1. Ocular (Eyepiece)
  2. Objectives
• What is the function of the ocular (eyepiece)?

  It is a short metal cylinder with lenses at both ends, often including a pointer.
• What is the typical magnification of most oculars?

  10x
• What are objectives in a microscope?

  Small tubes containing lenses, screwed into the nosepiece.
• What are the types of objectives and their magnifications?

  • Scanning Power Objective (Scanner): Magnifies 4x to 5x.
  • Low Power Objective (LPO): Magnifies 10x to 15x.
  • High Power Objective (HPO): Magnifies 40x to 45x.
  • Oil Immersion Objective (OIO): Magnifies 97x to 100x.
• What are the care instructions for a microscope?

  • Carrying: Use both hands and carry upright.
  • Cleaning: Clean before and after use with lens paper.
  • Adjustments: Do not force adjustments; call instructor if needed.
  • Inspection: Inspect before use and report damages.
  • Positioning: Use in upright position to avoid spills.
  • Before Returning: Ensure scanning objective is in place and wrap cords securely.
• What is the basic unit of life?

  Cells
• How do plant cells differ from animal cells?

  Plant cells contain a cell wall and chloroplasts, while animal cells lack these structures.
• What is compartmentalization in plant cells?

  • Plant cells have various membrane-bound organelles.
  • Biological membranes are semi-permeable.
  • The vacuole stores waste products, some of which crystallize.
• What is cell differentiation?

  It is the process by which cells acquire functional properties after division.
• What are the types of differentiated cells in plants?

  • Parenchyma
  • Collenchyma
  • Sclerenchyma (types of ground tissue cells)
  • Component cells of vascular tissue
• What are the characteristics of the cell wall?

  • Cellulosic and non-living.
  • Laid down by the protoplast during cell division.
  • Determines cell size and shape due to its rigidity.
• What is the middle lamella?

  It is the cementing substance between adjacent cells, composed of calcium pectate.
• What are pits in the cell wall?

  They are depressions or thin areas in the cell wall.