Freshman Biology: Introduction to Ecology

What is ecology?

The study of interactions between living organisms and their environment.

What are the characteristics of living organisms?

Living organisms must possess metabolism, growth, reproduction, response to stimuli, and homeostasis.

What is the difference between sexual and asexual reproduction?

Sexual reproduction involves the combination of genetic material from two parents, while asexual reproduction involves a single organism reproducing without the involvement of gametes.

What is a stimulus and a response?

A stimulus is any change in the environment that can provoke a response, while a response is the reaction of an organism to that stimulus.

What are the levels of ecological organization?

The levels are biosphere, biome, ecosystem, community, population, and organism.

What are the levels of classification in taxonomy?

The levels are domain, kingdom, phylum, class, order, family, genus, and species.

What is a cladogram?

A diagram that shows the evolutionary relationships among various biological species based on similarities and differences in their physical or genetic characteristics.

What is a dichotomous key?

A tool used to identify organisms based on a series of choices that lead the user to the correct name of a given item.

What are biogeochemical cycles?

Natural processes that recycle nutrients in various chemical forms from the nonliving environment to living organisms and back.

What is the water cycle?

The continuous movement of water on, above, and below the surface of the Earth, involving processes such as evaporation, condensation, precipitation, and infiltration.

What is the carbon cycle?

The process by which carbon is exchanged between the atmosphere, land, water, and living organisms, involving processes like photosynthesis and respiration.

What is the nitrogen cycle?

The series of processes by which nitrogen and its compounds are interconverted in the environment and in living organisms, including nitrogen fixation and denitrification.

What is population density?

The number of individuals of a species per unit area or volume.

What is logistic growth?

A model of population growth that describes how a population's growth rate decreases as it reaches carrying capacity.

What is exponential growth?

A model of population growth where the population increases at a constant rate, resulting in a J-shaped curve when graphed.

What are limiting factors?

Environmental conditions that restrict the growth, abundance, or distribution of a population within an ecosystem.

What is sustainability?

The ability to maintain ecological balance by avoiding the depletion of natural resources.

What is ecological succession?

The process of change in the species structure of an ecological community over time.

What is primary succession?

The development of an ecosystem in an area where no soil exists, such as after a volcanic eruption.

What is secondary succession?

The process of ecosystem recovery that occurs after a disturbance that does not destroy the soil, such as a forest fire.

What is a keystone species?

A species that has a disproportionately large effect on its environment relative to its abundance.

What is symbiosis?

A close and long-term interaction between two different species, which can be mutualistic, commensalistic, or parasitic.

What is the greenhouse effect?

The trapping of the sun's warmth in the planet's lower atmosphere due to the presence of greenhouse gases.

What are invasive species?

Non-native species that spread widely in a new habitat and can cause harm to the environment, economy, or human health.