BIO120 Notes - Vocabulary Flashcards

Vocabulary flashcards covering key terms and definitions from Lecture 1 through Lecture 8 topics.

Ecology

The science of how organisms interact with each other and their environment.

Biodiversity

The variety and abundance of species, genes, and ecosystems in a region.

Ecosystem

All the living organisms in an area plus the non-living physical and chemical environment.

Population

All individuals of a single species in a given place at a given time.

Community

All the species living together in a shared location.

Dispersal

Movement of individuals from one area to another, enabling range expansion or colonization.

Abiotic factors

Non-living environmental components such as climate, nutrients, and water.

Biotic factors

Living components of the environment including species interactions like competition and predation.

Climate warming

Increase in average temperatures that shifts species distributions and ranges.

Barrier to dispersal

Physical or biological barriers preventing movement between areas (e.g., oceans, mountains).

Limiting species range

Factors that constrain where a species can persist (e.g., dispersal, climate, food).

Gradient

A gradual change in environmental conditions across space or time, with species responding along the gradient.

Alfred Wallace

Naturalist whose ideas helped shape biogeography and the role of continental isolation in evolution.

Transplant experiment

Moving organisms to a new area to test survival and reproduction and infer dispersal limits.

Sixth Extinction

Ongoing mass extinction largely driven by human activity.

Paratoid gland

A toxin-producing gland in some toads that can cause harmful effects in predators.

Maladaptive

Traits that reduce fitness under current conditions, persisting due to lag in selection.

Trade-off

A situation where improvement in one trait comes at a cost to another trait.

Descent (homology)

Similarities due to shared ancestry (homologous traits).

Convergence

Independent evolution of similar traits in different lineages due to similar pressures.

Hutchinson’s n-dimensional hypervolume

A conceptual multi-axis space where each axis is an environmental factor defining a species’ niche.

ITCZ (Intertropical Convergence Zone)

Region near the equator where trade winds converge, driving rainfall and Hadley cell circulation.

Hadley Cells

Tropical atmospheric circulation with rising air at the equator and sinking air around 30° latitude.

Ferrel Cells

Mid-latitude atmospheric circulation cells between 30° and 60° latitude.

Polar Cells

Atmospheric circulation cells near the poles, with cold, sinking air.

Coriolis effect

Deflection of moving air and water due to Earth’s rotation, shaping wind patterns.

Easterly winds (Trade Winds)

Winds moving toward the equator from subtropical regions, deflected westward by the Coriolis effect.

Westerly winds

Winds moving from west to east in mid-latitudes, deflected eastward by Coriolis effect.

Roaring Forties

Strong westerly winds around ~40° latitude in the Southern Hemisphere.

Biome

A major ecosystem type characterized by climate, vegetation, and animal life.

Whittaker biome classification

A biome framework using temperature (y-axis) and precipitation (x-axis) to classify biomes.

Orographic effects

Rainfall patterns caused by air rising over mountains and releasing moisture.

Ecological niche modelling

Predicting species’ distributions by analyzing climate and niche dimensions.

Ecophysiology

Study of how physiological processes operate within ecological contexts.

Homeostasis

Maintenance of a stable internal environment to support organismal function.

Poikilotherm

An organism whose body temperature varies with the environment (cold-blooded).

Homeotherm

An organism that maintains a relatively constant internal body temperature (warm-blooded).

Bergmann’s rule

Endotherms tend to be larger in colder climates to conserve heat.

Allen’s rule

Endotherms in cold climates have shorter appendages to reduce heat loss; longer appendages in warm climates.

Countercurrent circulation

Heat transfer between adjacent arteries and veins to retain or shed heat efficiently.

Evaporative cooling

Cooling via evaporation of water (e.g., sweating, panting).

Stomata

Pores on leaf surfaces controlling gas exchange and water loss; regulated by ABA and water status.

C3 photosynthesis

Most common pathway; Rubisco fixes CO2 to form a 3-carbon compound; prone to photorespiration at high temps.

C4 photosynthesis

CO2-concentrating pathway using PEP carboxylase to reduce photorespiration.

CAM photosynthesis

Crassulacean acid metabolism; stomata open at night to conserve water.

PEP carboxylase

Enzyme with high CO2 affinity used in C4 photosynthesis.

Root foraging

Dynamic growth of roots toward nutrient-rich soil patches.

Legumes and nitrogen fixation

Symbiotic bacteria in root nodules convert atmospheric N2 to usable nitrogen for the plant.

Life history strategies: r vs K

r-strategists reproduce quickly with many offspring; K-strategists invest in survival with fewer offspring.

R0

Average number of daughters a female has during her lifetime.

Generation time

Average age at which females give birth; influences population growth rate.

Survivorship types (Type I/II/III)

Different life history curves describing mortality across age classes.

Semelparity

Reproduce once and die; often synchronized to satiate predators.

Iteroparity

Reproduce multiple times across a lifetime.

Life tables

Summaries of survivorship and fecundity by age or stage.

Density dependence

Population growth rate depends on population size due to resource limits.

Allee effects

Negative effects of low population density on growth or survival.

Lotka-Volterra

Mathematical models describing interactions (predation, competition) between species.

Competitive exclusion principle

Two species cannot occupy identical niches indefinitely; one excludes the other.

Character displacement

Evolution of divergent traits in coexisting species to reduce competition.

Invasive species; enemy release hypothesis

Non-native species thrive because natural enemies are absent or reduced in the new range.

Predator-prey and disease dynamics

Interactions where predators or parasites affect prey/host populations and disease spread.