Chapter 1: The Study of Life and Organizing Life

Vocabulary flashcards covering key terms from Chapter 1 notes on the study of life, science types, scientific reasoning, and cellular organization.

Basic Science

Pure science aimed at gaining knowledge without an immediate practical application; curiosity-driven.

Applied Science

Science applied to real-world problems with a product or service in mind.

Discovery Science

Inductive reasoning, describing natural structures and processes from observations and data.

Hypothesis-driven Science

Deductive reasoning, starting with a general principle to test with specific questions and experiments.

Observation

Careful noting of phenomena or events using senses or instruments.

Inductive Reasoning

Reasoning from specific observations to broad generalizations.

Deductive Reasoning

Reasoning from a general principle to specific conclusions or predictions.

Scientific Method

Ask a question, research, form a hypothesis, design/perform experiments, collect and analyze data, form conclusions, and communicate results.

Question

A focused inquiry to be addressed by research and experimentation.

Hypothesis

A tentative, testable explanation or educated guess that can be supported or refuted.

Scientific Theory

A broad, well-supported explanation repeatedly tested and modified as new evidence emerges.

Theory

In science, a well-supported, repeatedly tested explanation of natural phenomena.

Null Hypothesis

A default statement that there is no effect or relationship; tested against the alternative.

Controlled Experiment

An experiment where all variables are kept constant except the independent variable.

Independent Variable

The variable deliberately changed or manipulated by the experimenter.

Dependent Variable

The variable measured to assess the effect of the independent variable.

Control Group

A baseline group where no experimental treatment is applied.

Experimental Group

Group in which the independent variable is applied to observe its effect.

DNA

Deoxyribonucleic acid; the hereditary material carrying genetic instructions.

Gene

A basic unit of function and inheritance encoded by DNA sequences.

Allele

Different versions of a gene that cause variation in inherited traits.

Genome

The complete set of genetic material present in an organism or cell.

Mendelian Inheritance

Patterns of inheritance described by Gregor Mendel’s laws explaining trait transmission.

Cell Theory

All living organisms are composed of one or more cells; cells arise from pre-existing cells; cells contain DNA.

Gene Theory

Genes control inherited traits and are located on chromosomes.

Chromosome Theory of Heredity

Genes are located on chromosomes, which are passed from parents to offspring.

Theory of Evolution

Evolution is change over time in a population, driven by variation and differential reproduction.

Natural Selection

Differential reproductive success leading to changes in allele frequencies.

Descent with Modification

Offspring resemble but differ from their parents due to inherited variation.

Common Ancestor

The most recent shared ancestor of different species in a phylogenetic tree.

Phylogeny

The evolutionary history and relationships among organisms.

Taxonomy

Branch of biology that names and classifies species.

Domain

Highest taxonomic rank; groups living organisms into broad categories (e.g., Eukarya).

Emergent Properties

New properties arising at higher levels of organization due to interactions among components.

Levels of Biological Organization

From atoms to biosphere: atom, molecule, organelle, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere.

Prokaryote

A cell without a nucleus; circular chromosomes; no membrane-bound organelles; smaller size.

Eukaryote

A cell with a nucleus and membrane-bound organelles; larger and more complex.

Organelles

Specialized subunits within a cell that perform specific functions (e.g., nucleus, mitochondria, Golgi).

Nucleus

Membrane-bound organelle containing chromatin (DNA) and nucleolus; site of genetic information.

Mitochondrion

Organelle that produces most of the cell’s energy (ATP) via cellular respiration.

Chloroplast

Organelle in plant cells where photosynthesis occurs.

Ribosome

Molecular machine that synthesizes proteins; can be free or attached to the ER.

Endoplasmic Reticulum (ER)

Rough ER has ribosomes and makes secretory/membrane proteins; Smooth ER makes lipids.

Golgi Apparatus

Modifies, sorts, and packages proteins for secretion or delivery to organelles.

Endosymbiotic Theory

Eukaryotic organelles (mitochondria/chloroplasts) originated from symbiotic prokaryotes.

Unity in Diversity

All life shares fundamental features: DNA/RNA, universal genetic code, basic gene expression, and ribosomes.