Chapter 21: Populations And Communities Flashcards
Habitat
An environment that provides the things the organism needs to
live, grow, and reproduce.
Biotic Factors
The living parts of a habitat
Abiotic Factors
The nonliving parts of a habitat
Population
All the members of one species in a particular area
Community
All the different populations that live together in an area
Ecosystem
The community of organisms that live in a particular area,
along with their nonliving surroundings
Ecology
The study of how living things interact with one another and
their environments
Birth Rate
The number of births in a population in a certain amount of
time
Death Rate
The number of deaths in a population in a certain amount of
time
Immigration
Moving into a population
Emigration
Moving away from a population
Population Density
The number of individuals in an area of a specific size
Limiting Factor
An environmental factor that causes a population to decrease (can be food and water)
Parasite
An organism that benefits off of a host
Host
The organism that the parasite is on
Niche
The role of an organism in its habitat
Predation
An interaction in which one organism kills another for food
Successsion
The series of predictable changes that occur in a community over time
Predator
The organism that kills another organism for food
Prey
The organism that is killed for food
Primary Succession
The series of changes that occur in an area where no soil or organisms exist
Pioneer Species
The first species to populate an area
Secondary Succession
The series of changes that occur in an area where the ecosystem has been disturbed but there are still organisms living there
Symbiosis
A close relationship between two species that benefits at least
one of the species
Commensalism
A symbiotic relationship in which one species benefits and the
other species is neither helped or harmed.
Mutualism
A symbiotic relationship in which both species benefit
Parasitism
A symbiotic relationship that involves one organism living on
or inside the other organism and harming it
What must organisms obtain from their environment?
food, water, and shelter
How many habitats might an area have?
One area may contain many habitats depending on the
needs of organisms
What is an biotic factor?
A living part of an environment
What is a Abiotic factor?
The living factors of an environment (plants, animals, and fungi are all examples)
What is direct observation?
A method for determining population size where all members
of a population are counted.
Indirect Observation
A method for determining population size where signs of
organisms are used to estimate how many members are part of
a population.
What is sampling
A method for determining population size where a population is too large to be counted.
Explain mark and recapture
A method for determining population size where ecologists
capture organisms of a population and “mark” them to find and
study later.
What is the difference between predation and parasitism
Parasites don’t kill their hosts like a predator might kill its
prey
which events can cause succession in an environment
Floods, fires, earthquakes, mudslides (basically just major disasters)
identify several predator adaptations
- A bat’s echolocation
- An owl’s ability to see at
night - A crocodile’s retractable second eyelid
Be able to identify several prey adaptations
- An antelope’s speed
- a skunk’s spray
- a deers’ spots
Contrast primary and secondary succession.
Primary succession may take centuries before a fully formed
ecosystem comes into play
Secondary succession can take as little as a few months or around a
century.
