BIOL 150A - Class 2: Life & the Study of Life

Vocabulary flashcards covering key definitions, properties of life, biological organization levels, and model organisms based on class lecture notes.

Biology

The study of life, derived from 'bio' (life/living) and 'ology' (study of).

Metabolism

The processing of energy through any chemical reaction in living organisms, including growth, movement, and digestion.

Homeostasis

The maintenance of a steady state or stable internal environment that varies less than and remains distinct from external environmental conditions.

Tropisms

Plant responses to external stimuli, such as gravitropism, phototropism, and thigmotropism.

Taxis

Movement of an organism in response to a stimulus, such as chemotaxis (chemical stimulus) or phototaxis (light stimulus), derived from the Greek word for arrangement or order.

Evolution and Adaptation

The process through which species adapt to changing environments over time driven by natural selection and inevitable mutational changes in DNA sequences.

Molecules

Chemical structures consisting of at least two atoms held together by chemical bonds.

Macromolecules

Large biological molecules formed by combining smaller molecular units called monomers.

Organelles

Small specialized structures within a cell that perform specific cellular functions, such as the nucleus or ribosome.

Cells

The smallest fundamental units of structure and function in living organisms, which can exist as unicellular or multicellular forms.

Tissues

Groups of similar cells working together to carry out a common function.

Organs

Structures composed of groups of tissues collaborating to perform a shared function.

Organisms

Individual living entities composed of coordinated organs and organ systems.

Populations

Groups of individuals belonging to the same species living together in a specific geographic area.

Communities

All the interacting populations of different species occupying a shared area, encompassing all biotic factors.

Ecosystems

All the combined biotic (living) and abiotic (non-living) components in a given environment.

Model Organisms

Species extensively studied by biologists to understand basic biological processes, often possessing fully sequenced genomes to aid research.

Escherichia coli

A species of bacterium commonly used as a model organism in scientific research.

Saccharomyces cerevisiae

A species of single-celled fungus (yeast) used as a model organism in biology.

Drosophila melanogaster

The fruit fly species frequently utilized as a model organism in biological and genetic research.

Zea mays

Corn, a crop plant studied as a model organism in biological research.

Arabidopsis thaliana

A small flowering mustard plant widely used as a model organism in plant biology.

Populus trichocarpa

A tree model organism recognized as the first tree species to have its genome completely sequenced.

Phylogenetic Tree

A diagram illustrating evolutionary relationships and historical timelines among organisms, such as the origins of nonvascular plants (~470 mya), vascular plants (~425 mya), and seed plants (~360 mya).