unit one

BIOL0GY is the study of living organisms.

SCIENCE originates from the Latin word scientia, which means knowledge.

EXPERIMENTAL SCIENCE involves using experiments to gather information.

OUTGOING EFFORTS OF SCIENCE

  • Finding new information

  • Increasing human knowledge

  • Collecting evidence

STEPS OF THE SCIENTIFIC METHOD

  1. Observation & Asking Questions: Identify the problem.

  2. Background Research: Gather information.

  3. Constructing a Hypothesis: Formulate an educated guess.

  4. Experiment: Test the hypothesis.

    • Variables in Experiments:

      • Independent Variable: Does not change; e.g., temperature.

      • Dependent Variable: Affected by other variables; e.g., growth rate of an organism.

      • Controlled Variables: Factors that could influence the experiment but are kept constant.

  5. If the hypothesis is true, report the results. If false, revise and try again.

  6. Draw Conclusions.

  7. Report and Publish.

TERMS TO KNOW

  • Accuracy: The quality of being correct (precise).

  • Validity: The state of being true.

  • Reliability: The consistency or repeatability of results.

WRITING PARTS OF THE SCIENTIFIC METHOD

  1. Title

  2. Hypothesis (Research Question)

  3. Experimental Procedures

  4. Materials and Method

  5. Summary

  6. Conclusion

  7. Evaluation

  8. Acknowledgment

TOOLS OF BIOLOGISTS

  • Dissecting Kit: Used for dissection; includes forceps, scissors, and inoculator loops.

  • Petri Dish: Used to culture or grow microorganisms.

  • Pregnancy Urine Test: Determines if a woman is pregnant.

  • Polymerase Chain Reaction: Makes multiple copies of DNA.

  • Bunsen Burner: Used for heating.

  • Diabetic Blood Test: Measures sugar levels in the body.

  • Balance: Used to measure mass.

  • Thermometer: Measures temperature.

  • CT Scan: Obtains internal images of the body.

  • GPS: Identifies locations.

  • Centrifuge: Separates solids from liquids.

  • Pipets: Measure small liquid amounts.

  • Measuring Cylinder: Used for measuring or mixing chemicals.

  • Agar: Nutrient extracted from red algae used to culture microorganisms.

  • Data Logger: Records data.

  • pH Kit: Measures the pH of soil and water.

  • Theodolite: Measures the height of trees.

  • Quadrant: Measures the relationship of organisms in an environment.

  • Transect Line: Shows type and change in each quadrant.

  • Microscope:

    1. Optical Microscope (Light Microscope): Uses a beam of light; only sees living cells.

    2. Electron Microscope: Uses a beam of electrons; has higher magnification and detail; cannot view living specimens.

PARTS OF A MICROSCOPE

  • Eyepiece (Ocular Lens): Lens you look through, typically 10x or 15x magnification.

  • Objective Lenses: Primary lenses for specimen magnification (4x, 10x, 40x, 100x).

  • Stage: Platform for the slide; often has clips to hold it in place.

  • Illuminator: Light source below the specimen.

  • Coarse Adjustment Knob: Brings specimen into general focus.

  • Fine Adjustment Knob: Fine-tunes the focus.

  • Arm: Part to hold when carrying the microscope; connects the tube to the base.

  • Base: Bottom structure for support.

  • Diaphragm/Iris: Adjusts light reaching the specimen.

  • Condenser: Focuses light on the specimen.

MAGNIFICATION

  • Magnification: Enlargement of an object.

  • Resolution: Ability to distinguish between two points.