Chapter 1: The Study of Life Flashcards
Define biology.
The scientific study of life, including its structure, function, growth, evolution, distribution, and interactions.
List the 8 properties of life with examples.
Order (e.g., cells in a leaf).
Sensitivity/Response (e.g., plants bending toward light).
Reproduction (e.g., bacteria dividing).
Adaptation (e.g., polar bear fur for insulation).
Growth & Development (e.g., tadpole → frog).
Regulation/Homeostasis (e.g., sweating to cool down).
Energy Processing (e.g., photosynthesis).
Evolution (e.g., antibiotic resistance in bacteria).
Contrast inductive and deductive reasoning.
Inductive: Specific observations → general conclusion (e.g., “All observed swans are white → All swans are white”).
Deductive: General premise → specific prediction (e.g., “All humans need oxygen → John needs oxygen”).
What are the 7 steps of the scientific method? Use the “warm classroom” example.
Observation: Classroom is warm.
Question: Why is it warm?
Hypothesis: “The AC is broken.”
Prediction: If AC is fixed, temperature drops.
Experiment: Repair AC and measure temperature.
Results: Temperature remains high.
Conclusion: Hypothesis rejected; test new hypothesis (e.g., thermostat malfunction).
Define homeostasis and provide a mammalian example.
Maintaining stable internal conditions. Example: Human body temperature regulated at ~37°C via sweating/shivering.
Differentiate basic science and applied science.
Basic: Knowledge for its own sake (e.g., studying starfish development).
Applied: Solving specific problems (e.g., designing a pacemaker).
List the 12 levels of biological organization from atom to biosphere.
Atom
Molecule
Organelle
Cell
Tissue
Organ
Organ System
Organism
Population
Community
Ecosystem
Biosphere
What are the three domains of life? Describe each.
Bacteria: Prokaryotic, common (e.g., E. coli).
Archaea: Prokaryotic, extremophiles (e.g., thermophiles).
Eukarya: Eukaryotic (plants, animals, fungi, protists).
What is a phylogenetic tree? Label its parts.
A diagram showing evolutionary relationships. Parts:
Branches: Lineages.
Nodes: Common ancestors.
Tips: Extant species.
Example: Figure 1.17 (domains of life).
Name 5 subdisciplines of biology and their focus.
Molecular Biology (DNA/proteins).
Ecology (ecosystems).
Microbiology (microbes).
Genetics (heredity).
Zoology (animals).
What is the IMRAD structure of scientific papers?
Introduction: Background and hypothesis.
Methods: Experimental design.
Results: Data collected.
Discussion: Interpretation and implications.
Why is peer review essential in science?
Ensures research is valid, original, and accurate before publication. Example: Flawed studies are rejected or revised.
How does evolution unify biology?
Explains diversity through natural selection (e.g., Darwin’s finches’ beak adaptations).
Define scientific theory vs. hypothesis.
Theory: Well-supported explanation (e.g., evolution).
Hypothesis: Testable prediction (e.g., “If X, then Y”).
What did Carl Woese discover?
Reclassified life into 3 domains using ribosomal RNA, showing Archaea are distinct from Bacteria.
What are emergent properties? Give an example.
Properties arising from interactions of components. Example: Consciousness from brain neurons.
Define serendipity in science. Provide an example.
Accidental discoveries. Example: Alexander Fleming discovering penicillin from mold contamination.
Why aren’t viruses considered alive?
Lack cells, metabolism, and cannot reproduce without a host (e.g., influenza virus).
Explain variables and controls in an experiment. Use the breakfast example.
Variable: Factor tested (e.g., eating breakfast).
Control: Baseline for comparison (e.g., skipping breakfast).
What is falsifiability? Why is it critical?
A hypothesis must be disprovable. Example: “All life requires water” is falsified if life is found without it.
What is the Bohr model of the atom?
Electrons orbit the nucleus in shells (e.g., carbon has 2 electrons in the first shell, 4 in the second).
Describe the structure of DNA.
Double helix with nucleotides (adenine, thymine, cytosine, guanine) linked by hydrogen bonds.
What is the role of enzymes in biology?
Catalyze biochemical reactions (e.g., amylase breaking down starch).
What are radioactive isotopes? Give a use.
Unstable atoms emitting radiation. Use: Carbon-14 dating fossils.
Explain the significance of the Human Genome Project.
Mapped all human genes, advancing medicine and understanding of genetic diseases.
What is a buffer? How does it maintain pH?
Resists pH changes by absorbing/releasing H⁺ ions. Example: Bicarbonate buffer in blood.
What is cell theory?
All living things are made of cells; cells arise from pre-existing cells.
Define biodiversity. Why is it important?
Variety of life in an ecosystem. Important for resilience (e.g., rainforest species interdependence).
What is the role of fungi in ecosystems?
Decomposers breaking down organic matter (e.g., mushrooms recycling nutrients).
Describe natural selection with an example.
Traits enhancing survival/reproduction become more common. Example: Peppered moths during industrialization.
