Introductory Biology and Scientific Method Flashcards

A set of vocabulary flashcards reviewing basic biology concepts, biological hierarchy, cell types, experimental design, and metric system prefixes.

Biology

The scientific study of life and living organisms.

Emergent properties

New characteristics of a system that appear at a higher level of life. Example: If you put DNA, proteins, and lipids in a test tube, you just have a chemical soup. When they are organized into a cell, life (the ability to reproduce and metabolize) emerges.

Characteristics common to all living things

1. Made of cells; 2. Use energy; 3. Pass DNA to offspring.

Levels of Biological Organization

Hierarchy from smallest to largest: atom, molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere. Example: A heart (organ) is made of cardiac tissue, which is made of cells.

Cell

Smallest unit of life; at minimum, consists of plasma membrane, cytoplasm, and DNA.

Homeostasis

The ability of an organism to maintain a stable internal environment despite external changes. Example: Humans regulating body temperature at 37C.

Prokaryotic cells

Cells that lack a nucleus and membrane-bound organelles (e.g., bacteria, archaea).

Eukaryotic cells

Cells that have a nucleus and organelles (e.g., protists, fungi, plants, animals). Mnemonic: eUkaryote has a nUcleus.

Scientific method steps

Observation, Question, Hypothesis, Experiment, Data, Analysis, Conclusion.

Dependent variable

The factor measured in an experiment; changes in response to the independent variable. Example: Reaction time measured after caffeine intake.

Independent variable

The factor manipulated by the investigator to test its effect. Example: Amount of caffeine consumed.

Standardized Variables

Factors kept constant to ensure a fair test. Example: Same age group and gender for all participants in a study.

Control Group

The baseline group in an experiment that receives no treatment. Example: Group without caffeine.

Experimental Group

The group in an experiment that receives the treatment or variable being tested. Example: Group with caffeine.

Hypothesis

A testable explanation. Example: Caffeine improves alertness.

Scientific Theory

A well-supported, widely accepted explanation of natural phenomena. Example: Germ theory of disease.

Metric system prefixes

Sequence from largest to smallest: kilo- > hecto- > deci- > centi- > milli- > micro- > nano-.