biology chapter 5
what is a biotic factor?
a factor that is related to the activities of living things
what is a population?
a group of organisms of the same species that live in a specific geographical area
how is a niche different from a habitat?
a niche is a role or function of a species within a community. the habitat is where the species live.
what is parasitism?
a relationship between 2 species where one benefits (parasite) and the other species is harmed (the host)
what is symbiosis?
a relationship in which 2 organisms live in close association
what are limiting factors?
a situation that causes a decrease in population growth
what is a non native or introduced species?
a species that immigrates from another area
what is a keystone species?
a species that is critical to the function of the ecosystem in which it lives because it affects the survival and abundance of many other species in its community
what is mutualism?
a type of symbiosis where both organisms benefit
what is commensalism?
a type of symbiosis where one organism benefits and the other is neither helped nor harmed.
what is predation?
an interaction between 2 organisms in which one organism kills the other
why do organisms rarely occupy their entire fundamental niche?
b/c they usually have to compete with other species for limited resources.
why do organisms rarely occupy their entire fundamental niche?
because they usually have to compete with other species for limited resources
what are different factors limiting population growth?
biotic or abiotic
how might 2 different species divide resources?
by feeding in slightly different ways or in slightly different areas
what happens when 2 species require the same resources and one species is better than the other obtaining these resources?
competition
list 2 factors that contribute to risilency of an ecosystem
competition between species (interaction) high biodiversity (number of species)
what are density independent limiting factors?
factors that affect all populations regardless of size
what are density dependent limiting factors?
factors that depend on population size
what are some factors that affect population growth?
food predators
what is kleptoparasitism?
form of feeding in which one animal takes prey or other food from another that has caught, collected, or prepared the food
what is the entire set of conditions under which an animal can survive and reproduce itself?
fundamental niche
how have advances in technology allowed human populations to grow faster?
improving sanitation controlling disease allowing for efficient production of food
what are the characteristics of a population that grows exponentially
it grows slowly when it is small but grows quickly as it gets larger
what are biotic factors?
living factors that affect a population's growth
what are factors that have decreased the death rate of human population?
more food better health care improved sanitation safer water
what are abiotic factors?
nonliving factors that affect a population's growth
what is abiotic factor?
nonliving factors that affect population size
what is exponential growth
occurs when numbers increase by a certain factor in each successive time period
what it the parasite host relationship
parasites live off of the host and the host provides food source for the parasite. hosts try to keep parasites from infecting them
what is logistic growth?
population growth that starts with a minimum number of individuals and reaches a maximum depending on the carrying capacity of the habitat
who is the killer?
predator
what is the name of the one killed?
prey
what is a set of conditions actually used by a given animal after interactions with other species have been taken into account
realized niche
what are predator prey relationships?
species in various relationships develop adaptations in response to one another (coevolution)
what is coevolution?
the evolution of 2 or more species that is due to mutual influence
what is competitive exclusion?
the exclusion of one species by another due to competition
what is a fundamental niche?
the largest ecological niche where an organism or species can live without competition
what is the carrying capacity?
the largest population that an environment can support at a given time
what is realized niche?
the range of resources that a species uses, the conditions that the species can tolerate, and the functional roles that the species plays as a result of competition in the species' fundamental niche
what is a niche?
the unique position occupied by a species, both in terms of its physical use of its habitat and its function within an ecological community
what is immigration
to come to the region of individuals from another region
what is emigration
to leave a region to settle in another
