APES Quiz 2 (1.5, 1.6, 1.7, 1.8) Flashcards
producer (autotroph)
An organism that uses energy from the sun to produce usable forms of energy. Producers include plants, algae, and some bacteria.
consumer (heterotroph)
An organism that is incapable of photosynthesis and must obtain its energy by consuming other organisms.
food chain
The sequence of consumption from producers through tertiary consumers
food web
A complex model of how energy and matter move between trophic levels
trophic levels
The successive levels of organisms consuming one another
keystone species
A species that is not very abundant but has large effects on an ecological community
10% rule
The 10% rule approximates that as energy is transferred from one trophic level to the next, only about 10% of the energy is passed on. The loss of energy that occurs when energy moves from lower to higher trophic levels is lost largely through metabolic processes as heat.
native species
Native species live in their historical range, typically where they have lived naturally for thousand or millions of years. Native species are well-adapted to their environment and can thrive without much help.
invasive species
Invasive species are species that can live, and sometimes thrive, outside of their normal habitat. They often spread rapidly across large areas. Invasive species can sometimes be beneficial, but they are considered invasive when they threaten native species.
endangered species
A species that is in danger of extinction within the foreseeable future throughout all or a significant portion of its range.
population size
The total number of individuals within a defined area at a given time
population density
The number of individuals per unit area at a given time
population distribution
A description of how individuals are distributed with respect to one another
density-dependent factors
A factor that influences an individual’s probability of survival and reproduction in a manner that depends on the size of the population
density-independent factors
A factor that has the same effect on an individual’s probability of survival and the amount of reproduction at any population size
limiting resource
A resource that a population cannot live without and that occurs in quantities lower than the population would require to increase in size
carrying capacity
The limit of how many individuals in a population the environment can sustain
overshoot
When a population becomes larger than the environment’s carrying capacity
die-off
A rapid decline in a population due to death
survivorship curve
A graph that represents the distinct patterns of species survival as a function of age
K-selected species
A species with a low intrinsic growth rate that causes the population to increase slowly until it reaches carrying capacity
r-selected species
A species that had a high intrinsic growth rate, which often leads to population overshoots and die-offs
J-shaped curve
representative of the exponential growth model
S-shaped curve
representative of the logistic growth model
survivorship curve type I
a pattern of survival over time in which there is high survival throughout most of the life span, but then individuals start to die in large numbers as they approach old age
survivorship curve type II
a pattern of survival over time in which there is a relatively constant decline in survivorship throughout most of the life span
survivorship curve type III
a pattern of survival over time in which there is low survivorship early in life with few individuals reaching adulthood
ecological succession
The predictable replacement of one group of species by another group of species over time
primary succession
Ecological succession occurring on surfaces that are initially devoid of soil
secondary succession
The succession of plant life that occurs in area that have been disturbed but have not lost their soil
pioneer species
A species that can colonize new area rapidly and grow well in full sunshine
climax community
Historically described as the final stage of succession
generalist species
can survive in a wide range of conditions and eat a variety of foods
specialist species
have a limited diet and can only survive in a narrow range of environmental conditions
prescribed burns
a method of strategically burning forests to promote new succession and renewal of the biodiversity. It also helps to prevent
