AP Biology Module 1

the biosphere

all life on earth

ecosystems

all the living things in an area

communities

the array of organisms inhabiting an ecosystem

populations

all the individuals of a species living within the bounds of a specific area

organisms

individual living things

organs

a body part made of multiple tissues and has a specific function

tissues

groups of cells that work together, performing a specialized function

cells

life's fundamental unit of structure and function

evolution

a process of biological change in which species accumulate differences from their ancestors as they adapt to environments

competition

the struggle between organisms to survive in a habitat with limited resources

exploitation

a positive/negative interaction between two organisms in which one benefits and one is disadvantaged

predation

when an individual of one species (the predator) kills and eats an individual of another species (the prey)

herbivory

when one animal (the herbivore) feeds on producers (such as plants)

parasitism

when one organism, the parasite, derives its nourishment from another organism, the host, which is harmed in the process

mutualism

interaction that benefits members of both the interacting species (ex. bees pollinating flowers)

commensalism

interaction that benefits the individuals of one species but neither helps nor harms the other species (ex. trees provide shade for wildflowers that need low light conditions)

ecology

the study of relationships among biotic and abiotic factors

intermediate disturbance hypothesis

moderate levels of disturbance foster greater species diversity than high or low levels of disturbance (high levels cause environmental stress, low levels allow competition)

ecological succession

series of gradual changes that occur in a community following a disturbance

genetic diversity

the genetic variation within a population as well as the genetic variation between populations - often associated w/ adaptations to local conditions

species diversity

the number of species in an ecosystem or across the biosphere

ecosystem diversity

the variety of ecosystems on earth - focuses on interactions between species in an ecosystem

threats to biodiversity

habitat loss, introduced species, overharvesting, global change

population ecology

one species, changes in population over time, genetic biodiversity (high = healthy)

community ecology

multiple populations and multiple species, species biodiversity (high = healthy)

simpson's diversity index

total of number of organisms of one species vs all species

behavioral ecology

study of actions and responses in organisms

behavior

any action of an organism in response to a stimulus

external stimulus

audibles, pheromones, visual

internal stimulus

comes from organism (ex. hunger)

inate behavior

since birth, related to genetics and biology of an organism

learned behavior

modified action in response to experience or education

negative feedback

returns organism/system back to baseline or homeostasis (how the organism/system was before the stimulus)

positive feedback

amplifies a reaction within a system to move away from starting state (maintains behavior)

fitness

behavior increases ability to survive and reproduce

resource or niche partitioning

interaction where resources are divided between populations to avoid competition