LAB EXAM STUDY GUIDE

A set of flashcards covering key vocabulary and concepts related to the topics in the LAB EXAM STUDY GUIDE.

Biology

Study of life and living organisms.

Buffer

Substance that resists changes in pH when small amounts of acid/base are added.

Null Hypothesis (H₀)

States there is no effect or no difference.

Alternative Hypothesis (Hₐ)

States there is an effect or difference.

Prediction

The expected outcome based on your hypothesis.

Experimental Design

Framework of how you will test your hypothesis.

Independent Variable

The variable you change.

Dependent Variable

The variable you measure or observe.

Inductive Reasoning

Specific → General (observations → theory).

Deductive Reasoning

General → Specific (theory → prediction).

Quantitative

Numerical data.

Qualitative

Descriptive data.

Benedict’s Test

Detects reducing sugars; positive result indicated by a color change from blue to green/orange/red.

Lugol’s Iodine Test

Detects starch; positive result is blue-black.

Biuret Test

Detects proteins; positive result is violet/purple.

Ninhydrin Test

Detects free amino acids; positive result is purple or yellow (proline).

Sudan IV Test

Detects lipids; positive result shows a red layer on top.

Positive Control

Sample known to contain a substance.

Negative Control

Sample known not to contain a substance.

Acidic Solutions

Solutions with high H concentration, low pH.

Basic (Alkaline) Solutions

Solutions with high OH concentration, high pH.

Bromocresol Purple

pH indicator that turns yellow in acidic conditions and purple in basic conditions.

Total Magnification

Ocular lens × Objective lens.

Field of View (FOV)

Diameter of the visible area; decreases as magnification increases.

Resolution

Ability to distinguish two close points as separate.

Magnification

How large the image appears.

Prokaryote

Cell type without a nucleus; example: Bacteria.

Eukaryote

Cell type with a nucleus; examples: Plants, Animals.

Plasma Membrane

Controls entry and exit of substances in cells.

Cytoplasm

Contains organelles within the cell.

Ribosomes

Site of protein synthesis.

Chlorophyll a

Main photosynthetic pigment in plants.

Thylakoids

Flattened sacs inside chloroplasts that contain pigments.

Stroma

Fluid in chloroplasts where the Calvin cycle occurs.

Gram-Staining Process

Procedure to differentiate bacterial cell walls using specific stains.

Gram-Positive

Bacteria with thick peptidoglycan; stains purple.

Gram-Negative

Bacteria with a thin wall and outer membrane; stains pink.

Voltmeter

Measures electrical potential, used in detecting electron flow.

Solute

Substance dissolved in a solution.

Carbohydrates

Sugars/starches that serve as energy sources.

Lipids

Fats that serve for energy storage and membrane structure.

Proteins

Macromolecules that provide structure, enzymatic activity, and transport.

Nucleic Acids

Molecules like DNA and RNA that carry genetic information.