CHM-105 Common Elements & Biology Lab Practical 1 Study Guide

Symbols and Names of Common Elements (CHM-105)

  • Course Context: Reference guide for Fall-2026 CHM-105 homework on symbols and names of common chemical elements.
  • Chemical Element Symbols and Names:
    • Ag: Silver
    • Al: Aluminum
    • Ar: Argon
    • Au: Gold
    • B: Boron
    • Ba: Barium
    • Be: Beryllium
    • Br: Bromine
    • C: Carbon
    • Ca: Calcium
    • Cl: Chlorine
    • Cu: Copper
    • F: Fluorine
    • Fe: Iron
    • H: Hydrogen
    • He: Helium
    • Hg: Mercury
    • I: Iodine
    • K: Potassium
    • Li: Lithium
    • Mg: Magnesium
    • N: Nitrogen
    • Na: Sodium
    • No / Ne: Neon (transcribed as No for Neon on the reference table)
    • Ni: Nickel
    • O: Oxygen
    • P: Phosphorus
    • Pb: Lead
    • Pt: Platinum
    • S: Sulfur
    • Si: Silicon
    • Sn: Tin
    • U: Uranium
    • Zn: Zinc

Compound Light Microscope Anatomy and Optics (Lab Exercise 4)

LAB PRACTICAL 1 STUDY GUIDE document screenshot

  • Lab Exercise 4 Core Learning Objectives:

    • Master and describe the function of every component part of the microscope.
    • Accurately label all parts of a compound light microscope diagram.
    • Calculate Total Magnification when provided with lens power parameters.
    • Detail the step-by-step procedures for safely cleaning microscope lenses.

  • Microscope Components and Architectural Parts (Figure B):

    • Eyepiece (Ocular Lens): The uppermost lens assembly where the observer views the specimen; standard ocular lenses typically provide a initial magnification factor (e.g., 10×10\times).
    • Head: The upper structural housing holding the ocular lenses and optics, linking them to the revolving nosepiece.
    • Locking Screw: A thumbscrew that secures the optical head in place on the arm.
    • Diopter Adjustment: An adjustable ring on one or both eyepieces that allows fine-focus tuning to compensate for focal differences between the user's left and right eyes.
    • Revolving Nosepiece: A rotating circular turret located beneath the head that houses multiple objective lenses and allows rapid switching between magnifications.
    • Objectives (Objective Lenses): High-magnification optical lenses mounted on the nosepiece (such as scanning, low power, high power, and oil immersion lenses) that gather light directly from the specimen.
    • Slide Holder: A spring-actuated clip on the stage that clamps the microscope slide firmly in position.
    • Arm: The rigid upright handle connecting the upper optical assembly to the lower base, used for carrying the microscope.
    • Stage: The flat horizontal platform supporting the specimen slide during examination.
    • Coarse Focus (Coarse Focus Knob): The larger outer dial that moves the stage up and down in large increments for initial specimen focusing under low magnification.
    • Fine Focus (Fine Focus Knob): The smaller inner dial that moves the stage in sub-millimeter increments for high-precision focal adjustments under medium and high powers.
    • Condenser: A specialized sub-stage lens system that gathers and focuses light from the lamp into a concentrated cone directed onto the specimen.
    • Iris Diaphragm: An adjustable mechanical aperture mounted on the condenser that regulates the volume and contrast of light passing through the specimen.
    • Built-in Light Source: The internal light bulb or LED located within the base providing illumination through the optical train.
    • Stage Controls: Dual mechanical adjustment knobs positioned near the stage that translate the slide along the x-axis (left/right) and y-axis (forward/backward).
    • Brightness Adjustment: An electronic dial or rheostat controlling the intensity of light emitted by the light source.
    • On/Off Switch: Power switch activating electrical current to the internal illuminator.
    • Base: The heavy foundation of the compound microscope providing structural balance and housing internal electronics and lighting components.

  • Determination of Total Magnification:

    • Calculation Formula:     Total Magnification=Ocular Lens Magnification×Objective Lens Magnification\text{Total Magnification} = \text{Ocular Lens Magnification} \times \text{Objective Lens Magnification}
    • Application: Multiply the magnification factor of the eyepiece (ocular lens) by the magnification factor of the active objective lens currently engaged in the optical path.
    • Example Calculation: If the ocular lens is rated at 10×10\times magnification and the active objective lens is rated at 40×40\times magnification, the total specimen magnification is:     Total Magnification=10×40=400×\text{Total Magnification} = 10 \times 40 = 400\times

  • Microscope Lens Cleaning Guidelines:

    • Use exclusively high-purity, scratch-free optical lens paper to prevent damaging soft anti-reflective glass coatings.
    • Apply approved lens cleaning fluid or pure isopropyl alcohol directly to the paper rather than directly onto the lens.
    • Wipe in gentle circular motions from the center outward.
    • Never use standard paper towels, facial tissues, or clothing, as coarse plant fibers generate microscopic scratches on glass optical elements.

Histology and Tissue Classification (Lab Exercise 8-10)

  • Lab Exercise 8-10 Core Learning Objectives:

    • Formulate precise definitions for core biological terms: Histology and Stem Cells.
    • Identify the four fundamental tissue categories in human biology and articulate the primary function of each.
    • Correctly identify all histology slides from class laboratory exercises.
    • Categorize cell types, anatomical body distribution of epithelial tissues, exact names of epithelial varieties, connective tissue subtypes, muscle tissues, and neuronal structures.
    • Define the structure and function of the basement membrane.

  • Fundamental Histological Definitions:

    • Histology: The branch of microanatomy dedicated to the microscopic study of the structure, organization, and function of biological tissues.
    • Stem Cells: Unspecialized biological cells capable of indefinite self-renewal through cell division and equipped with the capacity to differentiate into various specialized cell lines.
    • Basement Membrane: A non-cellular extracellular matrix structure composed of protein fibers and glycoproteins that forms a thin layer beneath epithelial cell layers, anchoring them firmly to underlying connective tissue while acting as a selective filtration barrier.

  • The Four Primary Tissue Types and Functions:

    • Epithelial Tissue:
    • Primary Functions: Provides physical protection for body surfaces, lines internal organs and body cavities, controls tissue permeability, absorbs nutrients, secretes fluids, and forms glands.
    • Classification Rules: Classified according to cell shape (squamous, cuboidal, columnar) and cellular layering (simple, stratified, pseudostratified).
    • Anatomical Locations: Epidermis of the skin, lining of the digestive tube, respiratory tract linings, kidney tubules, blood vessel endothelium, and glandular organs.
    • Connective Tissue:
    • Primary Functions: Establishes a structural framework for the body, connects and binds distinct tissue layers, protects organs, stores energy reserves (adipose), and transports fluid and dissolved materials (blood).
    • Structural Composition: Consists of widely dispersed specialized cells embedded in an abundant extracellular matrix composed of ground substance and protein fibers (collagen, elastic, and reticular fibers).
    • Muscle Tissue:
    • Primary Functions: Specialized for contraction to produce active physical movement, maintain posture, propel fluids, and generate body heat.
    • Subtypes: Skeletal muscle (striated, voluntary, multinucleated), Cardiac muscle (striated, involuntary, branching cells connected by intercalated discs), and Smooth muscle (non-striated, involuntary, spindle-shaped cells).
    • Nervous Tissue (Neuron):
    • Primary Functions: Senses environmental stimuli, processes information, and propagates rapid electrical and chemical impulses across long distances across the nervous system.
    • Structural Components: Consists of specialized signaling units termed neurons (comprising dendrites, a soma/cell body, and an axon) along with supporting neuroglial cells.