Anatomy & Physiology Lab Study Guide: Safety, Microscopy, Cell Structure, and Tissues

Lab Safety and OSHA Pictograms

Introduction to Laboratory Safety

Understanding laboratory safety is essential for preventing accidents and ensuring a safe working environment in Anatomy & Physiology labs. OSHA pictograms are standardized symbols used to communicate hazards.

• Lab Safety: Refers to the set of rules and procedures designed to protect students and staff from harm.

• OSHA Pictograms: Visual symbols mandated by the Occupational Safety and Health Administration to indicate specific hazards (e.g., flammable, toxic, corrosive).

• Example: The flame pictogram indicates flammable materials; the skull and crossbones pictogram indicates acute toxicity.

Microscope Parts, Functions, and Terminology

Microscope Structure and Usage

Microscopes are essential tools for observing cells and tissues. Knowing the parts and their functions is crucial for proper use.

• Eyepiece (Ocular Lens): The lens you look through; typically 10x magnification.

• Objective Lenses: Multiple lenses with varying magnifications (e.g., 4x, 10x, 40x, 100x).

• Stage: Platform where the slide is placed.

• Coarse and Fine Focus: Knobs used to adjust the clarity of the image.

• Microscope Rules: Always start with the lowest magnification, handle with care, and clean lenses with lens paper only.

• Example: To view a cell, start with the 4x objective, focus, then switch to higher magnification.

Brownian Motion, Diffusion, Osmosis, and Filtration

Definitions and Laboratory Applications

These physical processes are fundamental to understanding how substances move in and out of cells.

• Brownian Motion: The random movement of particles suspended in a fluid due to collisions with molecules of the fluid.

• Diffusion: The movement of molecules from an area of higher concentration to an area of lower concentration.

• Osmosis: The diffusion of water across a selectively permeable membrane.

• Filtration: The process by which particles are separated from a fluid by passing through a membrane or filter.

• Example: In lab, diffusion can be observed by placing dye in water and watching it spread; osmosis can be demonstrated with dialysis tubing.

Key Equations:

• Rate of diffusion: $J = -D \frac{dC}{dx}$

• Osmotic pressure: $\Pi = iMRT$

Additional info: Worksheets may include experiments to visualize these processes and interpret results.

Metric System and Unit Conversion

Metric Problems and US-Metric Conversion

Accurate measurement is vital in scientific experiments. The metric system is the standard in science.

• Metric System: A decimal-based system of measurement (meters, liters, grams).

• Conversion: Changing units between US customary and metric systems (e.g., inches to centimeters).

• Example: 1 inch = 2.54 centimeters.

Key Equation:

• Unit conversion: $\text{Value in new units} = \text{Value in old units} \times \text{Conversion factor}$

Cell Structure and Function

Major Cell Components

Cells are the basic units of life, each with specialized structures that perform distinct functions.

• Nucleus: Contains genetic material (DNA); controls cell activities.

• Cytoplasm: Gel-like substance where organelles are suspended.

• Cell Membrane: Semi-permeable barrier that regulates entry and exit of substances.

• Mitochondria: Site of cellular respiration and energy production.

• Example: Red blood cells lack a nucleus, while muscle cells have many mitochondria.

Additional info: Students should be able to identify these structures in microscope images.

Stages of Mitosis and Interphase

Cell Cycle and Division

Mitosis is the process by which cells divide to produce identical daughter cells. Interphase is the period of cell growth and DNA replication.

• Interphase: Cell grows, performs normal functions, and replicates DNA.

• Prophase: Chromosomes condense, spindle fibers form.

• Metaphase: Chromosomes align at the cell's equator.

• Anaphase: Sister chromatids separate and move to opposite poles.

• Telophase: Nuclear membranes reform, chromosomes decondense.

• Cytokinesis: Division of the cytoplasm, resulting in two cells.

• Example: Onion root tip slides are commonly used to observe mitosis stages.

Key Equation:

• Cell cycle duration: $T_{\text{total}} = T_{\text{interphase}} + T_{\text{mitosis}}$

Epithelial and Connective Tissues

Identification, Characteristics, and Functions

Tissues are groups of cells with similar structure and function. Epithelial and connective tissues are two major types found in the body.

• Epithelial Tissue: Covers body surfaces and lines cavities; functions include protection, absorption, and secretion.

• Connective Tissue: Supports, binds, and protects organs; includes bone, blood, adipose, and cartilage.

• Identification: Based on cell shape, arrangement, and presence of extracellular matrix.

• Example: Simple squamous epithelium lines blood vessels; adipose tissue stores fat.

Tissue Type	Key Characteristics	Example Location
Epithelial	Cells tightly packed, little extracellular matrix	Skin, lining of GI tract
Connective	Cells scattered, abundant extracellular matrix	Bone, blood, cartilage

Additional info: Students should be able to identify tissue types from microscope images and descriptions.