Microscopes, Respiration, Solutions & Experiment Design

• A microscope's components each serve a specific purpose in magnifying and observing specimens.
• Microscopes use magnification to enlarge the image of small objects.
• The diameter of field of view is used to calculate the size of a specimen under a microscope.
• Metric scale conversions are essential for accurate measurements in scientific experiments.

Respiration

• Respiration experiments study how organisms exchange gases with their environment.
• Aerobic cellular respiration produces energy, water, and carbon dioxide.

Solutions

• Solution dilutions involve reducing the concentration of a solution.
• Benedict's reagent tests for reducing sugars, while Barfoed's reagent identifies monosaccharides.
• Reducing sugars can donate electrons, while non-reducing sugars cannot.
• Assays like Benedict's, Barfoed's, iodine, Biuret, and miscibility tests yield different outcomes based on the substrate.

Experiment Design

• A hypothesis makes a testable prediction about a phenomenon.
• The independent variable is manipulated, and the dependent variable is measured.
• Experimental groups receive the treatment, while control groups do not.
• Negative controls confirm the absence of an effect, while positive controls confirm the presence of an effect.

Osmosis

• Potato osmosis demonstrates how water moves across a semipermeable membrane in hypertonic solutions, affecting mass.
• The isotonic point is when there is no net water movement across the membrane.

Lab Equipment

• Lab equipment includes tools for measuring, mixing, and observing substances.
• Gas recording instruments measure gas exchange during respiration.
• Cumulative percent change in weight calculates the overall change in a sample's weight over time.
• Rate of change calculations (slope) determine how quickly a variable changes.
• Tonicity of solutions refers to their ability to cause water movement in or out of cells.
• Stock solution dilution calculations are used to prepare solutions of desired concentrations.
• Graphing cumulative percent change in weight visually represents weight changes over time.
• Percent change of concentration can be calculated from the slope of line graphs.
• Plotting rate of change versus concentration helps analyze the relationship between these variables.
• Aerobic respiration occurs in cells and involves the breakdown of glucose to produce energy, requiring oxygen.

Measuring Cellular Respiration

• Measuring cellular respiration assesses metabolic rate, typically in units of oxygen consumption per unit time per unit mass.
• Carbon dioxide production is measured using equipment; KOH absorbs carbon dioxide in respiration experiments.

Metabolic Rate

• Metabolic rate calculations determine the rate at which an organism consumes energy.
• Photosynthesis involves the use of specific wavelengths of light.
• Pigment chromatography separates pigments based on their properties using a solvent.
• The Rf value of pigments in chromatography is calculated to identify different pigments.
• The rate of photosynthesis is measured using NaHCO3 as a carbon source.
• Ectotherms rely on external sources for body heat, while endotherms generate their own body heat.