Chapter 1: The Scientific Study of Life

Comprehensive practice flashcards covering fundamental concepts in biology, organization levels, energy processing, reproduction, taxonomy, and the scientific method from Chapter 01.

What is biology?

Biology is the scientific study of life.

What is an organism?

An organism is a single living individual.

What are the basic units of life found in every living organism?

Cells are the basic units of life, and every organism consists of one or more cells.

What is the function of DNA in living cells?

DNA carries genetic information passed to the next generation, which cells use to produce proteins that carry out cell work.

What are the five shared characteristics that define life?

Organization; Energy; Internal constancy; Reproduction, growth, and development; and Evolution.

What is an atom?

An atom is the smallest chemical unit of a type of pure substance (element).

How is a molecule defined in biological organization?

A molecule is a group of joined atoms, such as DNA.

What is an organelle?

An organelle is a membrane-bounded structure that has a specific function within a cell, such as a chloroplast.

What is a cell?

A cell is the fundamental unit of life.

What is a tissue?

A tissue is a collection of specialized cells that function in a coordinated fashion.

What is an organ?

An organ is a structure consisting of tissues organized to interact and carry out specific functions.

What is an organ system?

An organ system consists of organs connected physically or chemically that function together.

What is the difference between a population and a community?

A population is a group of the same species living in the same place and time, whereas a community includes all populations occupying the same region.

What components form an ecosystem?

An ecosystem consists of both the living and nonliving components of an area.

What is the biosphere?

The biosphere is the global ecosystem, encompassing all parts of the planet and its atmosphere where life is possible.

What are emergent properties?

Emergent properties are qualities that arise at each level of biological organization due to interactions among components, where the whole system is greater than the sum of its parts.

How do primary producers obtain energy?

Producers extract energy and nutrients from the nonliving environment, such as sunlight or soil.

How do consumers obtain energy?

Consumers obtain energy and nutrients by eating other organisms.

What is the ecological role of decomposers?

Decomposers are consumers that obtain nutrients from dead organisms and organic wastes.

What is homeostasis?

Homeostasis is the process by which a cell or organism maintains internal constancy, such as optimal levels of temperature, nutrients, sugar, salt, and water.

Under what conditions is asexual reproduction most successful?

Asexual reproduction is most successful in unchanging environments because offspring are genetically identical to the single parent.

Why is sexual reproduction advantageous in changing environments?

Sexual reproduction generates genetic variation among offspring, making them different from both parents and better adapted to environmental changes.

What is the definition of evolution?

Evolution is genetic change over time in a population.

What is taxonomy?

Taxonomy is the branch of science that names and classifies organisms based on shared features, including structure, chemistry, and DNA sequences.

What are the eight levels of taxonomic hierarchy from most inclusive to least inclusive?

Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species.

What are the three domains of life?

Domain Bacteria, Domain Archaea, and Domain Eukarya.

What structural characteristic distinguishes prokaryotes from eukaryotes?

Prokaryotic cells lack nuclei and other internal membrane-bounded compartments, whereas eukaryotic cells have larger, more complex cells containing nuclei.

What are the characteristics of kingdom Protista?

Protists are a highly diverse group of eukaryotes that can be unicellular or multicellular and include both autotrophs and heterotrophs.

How do members of kingdom Fungi obtain nutrients?

Fungi are heterotrophs that obtain nutrients by external digestion.

How do members of kingdom Animalia obtain nutrients?

Animals are multicellular heterotrophs that obtain nutrients by ingestion.

How do members of kingdom Plantae obtain nutrients?

Plants are multicellular autotrophs that capture light energy from the sun.

What is a hypothesis in scientific inquiry?

A hypothesis is a potential explanation for an observation that can be supported or falsified by experimental data.

What is an independent variable?

An independent variable is the factor that an investigator intentionally manipulates in an experiment.

What is a dependent variable?

A dependent variable is the factor measured to determine whether it is affected by the independent variable.

What is a standardized variable?

A standardized variable is any variable intentionally held constant for all subjects in an experiment.

What is the role of a control group in an experiment?

A control group provides a basis for comparison with treatment groups and may remain untreated or receive a placebo.

What does statistical significance measure in experimental analysis?

Statistical significance assesses the probability that the experimental results arose purely by chance.

How does a scientific theory differ from a hypothesis?

A scientific theory is a broader, comprehensive explanation for natural phenomena supported by a large body of evidence, whereas a hypothesis is a specific, testable explanation.

What prediction did Charles Darwin make regarding orchids with long nectar tubes?

Darwin predicted that a moth with an equally long tongue existed to pollinate the orchid, a prediction based on evolutionary theory that was confirmed 30 years later.