Comprehensive Biology and Evolution: Scientific Method, Cell Theory, Data Types, and Darwinian Principles

discovery-based science

To describe the natural world.

hypothesis-driven science

To explain the natural world using hypotheses and experiments.

hypothesis

A proposed explanation for a natural observation that is tested with evidence.

attributes of theories

Generate multiple predictions, accurate, consistent with large amounts of data.

theory

An explanation supported by large amounts of data over long periods of time.

inductive reasoning

Moves from specific observations to general conclusions.

deductive reasoning

Moves from general principles to specific predictions.

scientific method order

Observation → Hypothesis → Experimental run → Data → Hypothesis review.

independent variable

The variable that is manipulated.

dependent variable

The variable that is measured.

controlled variable

A factor kept constant across all groups.

control group

A group not exposed to the experimental treatment.

treatment group

The group exposed to the experimental manipulation.

independent variable in graph

Days.

missing Y-axis labeling

Units for temperature.

qualitative data

Descriptive, unordered categories.

quantitative data

Numerical, measurable, continuous.

ordinal data

Ordered categories, no consistent spacing.

interval data

Ordered data with consistent numerical spacing.

ordinal and interval data

Quantitative.

inside-out method

Methods/Materials → Results → Discussion → Conclusion → Introduction → Abstract → Title.

seven characteristics of life

Cells & organization, energy use & metabolism, environmental response, regulation & homeostasis, growth & development, reproduction, biological evolution.

three principles of Cell Theory

All living things are composed of cells; All cells come from preexisting cells; Cells are the smallest unit of life.

Schleiden & Schwann

Proposed that all living things are composed of cells.

Hooke

Discovered the microscope.

Leeuwenhoek

Refined magnification power.

organelle level

FALSE: The organelle level is above the cellular level.

community level

TRUE: The community level is above the population level.

correct convention in type

Caulobacter crescentus (italicized).

correct convention in writing

Caulobacter crescentus (underlined).

three domains of life

Bacteria → unicellular prokaryotes; Archaea → unicellular prokaryotes; Eukarya → unicellular & multicellular eukaryotes.

four kingdoms of life

Protista, Fungi, Plantae, Animalia.

Charles Darwin

Observed variation in birds and studied evolution.

Darwin's voyage

Voyage of the Beagle.

Darwin's publication

On the Origin of Species.

Darwin's description of evolution

Descent with modification through variation and natural selection.

microevolution

Change in one gene in a population over time.

macroevolution

Formation of new species.

Darwinian fitness

The relative likelihood that a genotype will contribute to the gene pool of the next generation compared to others.

Darwinian fitness measure

Reproductive success.

population-wide average

Mean fitness.

five classes of evolutionary mechanisms

Selection, random mutation, genetic drift, gene flow, non-random mating.

genetic drift

Random fluctuations in allele frequencies between generations, often leading to fixation or loss.

bottleneck effect

A hurricane reduces a bird population; survivors are mostly light-colored, so future generations are also light.

founder effect

The Amish population in Pennsylvania has high frequency of Ellis-van Creveld syndrome due to small founding population and inbreeding.

gene flow

Gain or loss of alleles due to immigration or emigration.

gene flow vs genetic drift

Drift = allele changes within a population, random; Gene flow = allele changes due to movement between populations.

inbreeding

Mating between genetically related individuals, increasing homozygosity, often in small populations.