General Biology 1 Microscopy & Micrometry PDF

Q1 – 1st Sem. | GENERAL BIOLOGY: Ms. Jess Brigola GENERAL BIOLOGY 1 | H.M. Revolving Nosepiece: holds the objectives in place and allows changing of objectives Micro...

Q1 – 1st Sem. | GENERAL BIOLOGY: Ms. Jess Brigola GENERAL BIOLOGY 1 | H.M. Revolving Nosepiece: holds the objectives in place and allows changing of objectives Microscopy and Micrometry Stage: where we put the slide (specimen) Microorganisms Stage Clip: holds the slide in place Coarse Knob (bigger): moves the stage up and - living things that the naked eye cannot see down; use it for the scanner and LPO - A microscope is used Fine Adjustment Knob (smaller): it brings the image into a sharper focus; use it for the HPO There is more to the picture than meets the eye - Neil and OIO Young. MAGNIFYING PARTS: enlarges the image produced in a Microscopes microscope - Used to view organisms that the naked eye Objective Lens: captures the light from the light cannot see source and magnifies the image (scanner: red - It's not clear who invented the first microscope, 4x, Low Power Objective: yellow 10x, High but the Dutch spectacle maker Zacharias Power Objective: blue 40x, Oil Immersion Janssen is credited with making the earliest Objective: white 100x) compound microscopes (two lenses) Eyepiece/Ocular Lens: the part in which the - Monocular: one eyepiece viewer peeks through to view the specimen (can - Binocular: two eyepieces be monocular: one eyepiece, or binocular: two Types of Microscopes: eyepieces) Compound Light Microscope ILLUMINATING PARTS: designed to transmit light - consists of ocular lenses(binocular) and Iris Diaphragm: allows you to adjust the amount objective lenses of light passing through the specimen - max. 1000x Mirror: used for reflection of light rays into the microscope (used in non-electric microscope) Stereoscope Light Source: provides light (used in electric microscopes) - also called a dissecting microscope - max. 100x Electron Microscope - uses a beam of electrons to magnify an image - max. 50,000x - Transmission EM: 2d - Scanning EM -3d Atomic Force Microscope - uses a stylus to detect the surface of the sample - imaging bacteria Magnification - max: 1,000,000x - The ability of a microscope to produce an image Confocal Microscope of an object at a scale larger than its actual size - produces an image of a thin plane on a think Magnification Power specimen - couples a laser source to a fluorescent - The degree to which the image of an object is microscope. enlarged when viewed through the microscope Parts of a Compound Microscopes MAGNIFYING PARTS: MECHANICAL PARTS: provides support and protection Eyepiece/Ocular Lens to other parts of the microscope - Usually 10x Base: is mainly used to balance and stabilize the Objective lens microscope Body Tube: a hollow tube where light passes - Scanner: 4x through from the objective lens to the ocular lens - LPO: 10x Arm: connects the head and the base of the - HPO: 40x microscope and is used as a handle for carrying - OIO: 100x Hannah M. | 11-04 |’24 Q1 – 1st Sem. | GENERAL BIOLOGY: Ms. Jess Brigola Equation for Total Magnification (TM): TM = (eyepiece mag.) (objective mag.) Example: (10x)(40x) = 400x (TM) Field of View - The maximum area visible through the lenses of a microscope Equation for Field of View (FOV): FOV = Field number/ Total Magnification **Remember that the diameter of the field of view changes depending on the power of the objectives --------------------------------------------------------------------------- Micrometry - A technique used to measure microscopic objects Micrometer - An instrument used to measure the size of an object viewed under the microscope - Also refers to the unit of measurement, um How to measure the size of the specimen Technique 1: ESTIMATED SIZE - ES = FOV/Number of specimens across Technique 2: ACTUAL SIZE - Step 1: Calculate for CALIBRATION FACTOR (CF): used to calibrate the ocular micrometer (an unknown value) using a stage micrometer (a known value) STAGE MICROMETER – dimensions change based on the objective lens used; has a known value (10 microns per space/division) OCULAR MICROMETER – dimensions won’t change even if the objective lens is switched; has an unknown value FORMULA 1: use only if micrometers are not fully seen in the FOV CF = Stage micrometer unit (10um)/Ocular micrometer unit FORMULA 2: use only if micrometers are fully seen in the FOV CF = Stage micrometer/Ocular Micrometer - Step 2: Calculate for the ACTUAL SPECIMEN (AS) FORMULA: AS = (CF) (Ocular units occupied) Hannah M. | 11-04 |’24