Unit 8 AP Biology Vocab ALL

competition

a -/- interaction that occurs when individuals of different species both use a resource that limits the survival and reproduction of each species

niche partitioning

natural selection drives/pushes competing species into different patterns of resource use, or different niches

predation

an interaction in which an individual of one species, the predator, kills and eats an individual of the other species, the prey

herbivory

a +/- ecological interaction in which an organism eats part of a plant or algae

symbiosis

an ecological relationship between organisms of two different species that live together in direct and intimate contact

parasitism

a +/- ecological interaction in which one organism, the parasite, benefits by feeding upon another organism, the host, which is harmed; some parasites live within the host, while the other feeds on the host’s external surface

mutualism

a +/+ ecological interaction that benefits individuals of both interacting species

commensalism

a +/0 ecological interaction that benefits the individuals of one species but neither harms nor helps the individuals of the other species

facilitation

a +/+ or +/0 ecological interaction when one species has a positive effect on the survival and reproduction of another’s without the intimate association of symbiosis

biodiversity

the variety of different organisms within a given area ecosystem

species richness

the number of species in a biological community

relative abundance

the proportional abundance of different species in community

biodiversity

the variety of different organisms within a given area/ecosystem

keystone species

a species that is not necessarily abundant in a community yet exerts strong control on community structure by the nature of its ecological role or niche

ecological succession

transition in the species composition of a community following a disturbance; establishment of a community in an area virtually barren of life

primary succession

a type of ecological succession that occurs in an area where there were originally no organisms present and where soil has not yet farmed

secondary succession

a type of succession that occurs where an exiting community has been cleared by some disturbance that leaves the soil or substrate intact

disturbance

a natural or human caused event that changes a biological community and usually removes organisms from it

heterozygote advantage

greater reproductive success of heterozygous individuals compared with homozygotes; tends to preserve variation in a gene pool

biomagnification

compounds like toxins/pollutants/contaminants increase in concentration in higher trophic levels/ the process of altering a biological organism or material using genetic, molecular, or mechanical methods to change its properties or function

eutrophication

a process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria

invasive species

a species moved by humans, either intentionally or accidentally, from its native location to a new geographic region

Ethology

The study of how evolutionary behaviors shape inherited behaviors and the ways that animals respond to specific stimuli

Behavior

Individually, an action carried out by muscles or glands under control of the nervous system in response to a stimulus; collectively, the sum of an animal’s responses to external and internal stimuli

Proximate cause

How a behavior occurs or how it is modified

Innate behaviors

Animal behaviors that is developmentally fixed and under strong genetic control

Learned behaviors

Behaviors shaped by experiences

Ultimate cause

Why a behavior occurs (in context of natural selection)

Fixed action pattern

In animal behaviors, a sequence of unlearned acts that is essentially unchangeable and, one initiated, usually carried to completion

Stimulus response chain

A stimulus in which the response to each stimulus is itself a stimulus for the next behavior

Directed movements

Movements towards or away from a stimulus

Pheromones

In animals and fungi, a small molecule released into the environment that functions in communication between members of the same species

Sign stimulus

An external sensory cue that triggers a fixed actions pattern by an animal

Migration

A regular, long-distance change in location

Kinesis

A change in the rate of movement or the frequency of turning movements in response to a stimulus; nondirectional

Taxis

An oriented movement toward or away from a stimulus

Phototaxis

Movement in response to light

Chemotaxis

Movement in response to chemical signals

Geotaxis

Movement in response to gravity

Learning

The modification of behavior as a result of specific experiences

Imprinting

In animal behaviors, the formation at a specific stage in life of a long-lasting behavioral response to a specific individual or object

Spatial learning

The establishment of a memory that reflects the environment’s spatial structure

Cognitive map

A neural representation of the abstract spatial relationships between objects in an animal’s surroundings

Associative learning

The acquired ability to associate one environmental feature (such as a color) with another (such as danger)

Social learning

Modification of behavior through the observation of other individuals

Foraging

The seeking and obtaining of food

Altruism

Selflessness; behavior that reduces an individual’s fitness while increasing the fitness of another individual

Phototropism

The bending of a plant or other organism in response to light, either toward the source of light (positive phototropism) or away from it (negative phototropism)

Photoperiodism

A physiological response to photoperiod, the interval in a 24-hour period during which an organism is exposed to light

Metabolic rate

The total amount of energy and animal uses in a unit of time

Ecosystem

All the organisms in a given area as well as the abiotic factors with which they interact; one or more communities and the physical environment around them

Biotic

Pertaining to the living factors (the organisms) in an environment

Abiotic

Nonliving; referring to the physical and chemical properties of an environment

Endotherm

Use thermal energy from food/internal metabolism to maintain body temperatures

Ectotherm

Use external sources (I.e. sun/shade or the organisms) to regulate their body temperature

Primary producer

An autotroph, usually a photosynthetic organism

Heterotrophs

An organism that obtains organic food molecules by eating other organisms or substances derived from them

Primary consumer

An herbivore; an organism, that eats plants or other autotrophs

Secondary consumer

A carnivore that eats herbivores

Tertiary consumer

A carnivore that eats other carnivores

Quaternary consumer

Animals (especially carnivores) that eat tertiary consumers (if they have no natural predators, they’re known as an apex predator)

Decomposer

An organism that absorbs nutrients from nonliving organic material such as corpses, fallen plant material, and the wastes of living organisms and converts them to inorganic forms; a detritivore

Scanvenger

Animals that consume dead/decaying organisms (plants or animals)

Biogeochemical cycles

Any of the various chemical cycles, which involve both biotic and abiotic components of ecosystems

Food chain

The pathway along which food energy is transferred from trophic level to trophic level, beginning with producers

Food web

The interconnected feeding relationships in an ecosystem

Primary production

The amount of light energy converted to chemical energy (organic compounds) by autotrophs in an ecosystem during a time period

GPP

The total primary production of an ecosystem

NPP

The gross primary production of an ecosystem minus the energy used by the producers for respiration

Secondary production

The amount of chemical energy in consumers’ food that is converted to their own new biomass during a given time period

Demography

The study of changes over time in the vital statistics of population, especially birth and death rates

Life table

A summary of the age-specific survival and reproductive rates of individuals in a population

Survivorship curve

A plot of the number of members of a cohort that are still alive at each age; one way to represent age-specific mortality

Exponential growth

Growth of a population in an ideal, unlimited environment represented by a J-shaped curve when population size is plotted over time

Life history

The traits that affect an organism’s schedule of reproduction and survival

Density-dependent regulation

As a population increases, factors can limit or reduce growth by decreasing birth rate and increasing death rate

Density independent regulation

Factors that exert their influence on population size, but the birth/death rate of a population does not change

K-selection

Selection for life history traits that are sensitive to population density

R-selection

Selection for life history traits that maximize reproductive success in uncrowded environments (low population density).

Population

A group of individuals of the same species that live in the same area and interbreed, producing fertile offspring

Population ecology

The study of populations in relation to their environment, including environmental influences on population density and distribution age structure, and variations in population size

Density

The number of individuals per unit area or volume

Dispersion

The pattern of spacing among individuals within the boundaries of a population

Logistic growth

Population growth that levels off as population size approaches carrying capacity

Community

All the organisms that inhabit a particular area; an assemblage of populations of different different species living close enough together for potential interaction

Habitat

A place or part of an ecosystem occupied by an organism

Ecological niche

The sum of a species’ use of the biotic and abiotic resources in its environment

Fundamental niche

The niche potentially occupied by species if there were no limiting factors (predators, competitors, etc.)

Realized niche

The portion of the fundamental niche the species actually occupies

Interspecific interactions

A relationship between individuals of two or more species in a community