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Midterm study guide pt2

LAB 3: Organic Chemistry

Overview of Organic Chemistry

  • Organic Chemistry: The study of carbon-containing compounds and their properties.

  • Inorganic Chemistry: The study of inorganic compounds, which do not primarily contain carbon.

  • Biochemistry: The branch of science that explores the chemical processes within and related to living organisms.

Key Terms

  • Monomers and Polymers: Monomers are small molecular units that combine to form polymers through chemical reactions.

  • Dehydration Synthesis: A chemical process where two molecules are bonded together with the removal of a water molecule.

  • Hydrolysis: The chemical breakdown of a compound due to reaction with water.

Carbohydrates

  • Monosaccharides: Simple sugars (e.g., glucose, fructose).

  • Disaccharides: Formed by two monosaccharides (e.g., sucrose).

  • Polysaccharides: Long chains of monosaccharide units (e.g., starch, glycogen, cellulose).

Tests for Carbohydrates

  • Benedict's Test: Tests for reducing sugars; positive result indicates presence of reducing sugars with a color change.

  • Iodine Test: Tests for starch; a positive test will yield a blue-black color.

Lipids

  • Types of Lipids: Includes fatty acids, triglycerides (fats and oils), waxes, sterols, and glycerol.

Tests for Lipids

  • Greasy Spot Test: Indicates the presence of lipids by leaving a translucent spot on paper.

  • Sudan Test: Tests for lipids using Sudan dye which stains lipids red.

  • Emulsion Test: Determines the presence of fats in a solution; creates an emulsion when a lipid is mixed with water in the presence of an emulsifier.

Proteins

  • Amino Acids: Building blocks of proteins, containing an amino group, carboxyl group, and a side chain.

  • Peptide Bonds: Bonds that link amino acids together to form proteins.

Test for Proteins

  • Biuret Test: Detects proteins. A color change to violet indicates the presence of peptide bonds.

LAB 4: Using the Microscope

Microscope Basics

  • Parts and Functions: Understanding magnification, parfocal settings (stays in focus when switching objectives), resolution, working distance, field of view, iris diaphragm, and depth of focus.

Slide Preparation

  • Types of slides include prepared slides (w.m. for whole mount, I.s. for intermediate section, x.s. for cross-section), specimens, wet mounts, and cover slips.

Types of Cells

  • Cell Types: Unicellular (single-celled organisms), colonial (groups of genetically identical cells), and multicellular (complex organisms).

Microscopy Techniques

  • Stereomicroscope: Provides a 3D view of specimens.

  • Electron Microscope: Uses electrons for high-resolution images; includes transmission (TEM) and scanning (SEM) electron micrographs.

LAB 5: Cells and Cell Structure

Cell Structure and Functions

  • Prokaryotic vs. Eukaryotic: Prokaryotes lack a defined nucleus; eukaryotes have membrane-bound organelles.

  • Organelles: Structure and functions of organelles in plants (e.g., chloroplasts) and animals (e.g., mitochondria).

Slides and Staining Techniques

  • Prepared slides include Oscillatoria, Spirillum, cheek cells, Amoeba, blood cells, Elodea, potato slices, and onion skin.

  • Staining techniques: Methylene blue and iodine stain.

LAB 6: Cellular Transport Mechanisms

Types of Transport Mechanisms

  • Selectively permeable: Cell membranes that allow certain substances to pass.

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

  • Concentration Gradient: Difference in concentration of a substance across a space.

  • Brownian Movement: Random motion of particles in a fluid.

  • Osmosis: Diffusion of water across a selectively permeable membrane.

Transport Terms

  • Passive Transport: Movement of molecules through the cell membrane without energy input.

  • Equilibrium: Balance of concentrations.

Types of Solutions

  • Hypertonic: Higher concentration of solutes outside the cell; causes crenation in cells.

  • Hypotonic: Lower concentration of solutes outside the cell; can lead to hemolysis.

  • Isotonic: Equal concentration of solutes in and out of the cell.

Cellular Effects

  • Plasmolysis: The process in which cells lose water in a hypertonic solution.

  • Turgor: Pressure of the cell contents against the cell wall, crucial for plant structure.

Important Notice

  • Lab Access: All labs will be closed before the practical exam for setup. Students may only enter the labs during their scheduled lab times for testing purposes.