Chapter 1 - Populations and Ecosystems Flashcards
What is a community?
All the populations of different organisms (and species) living and interacting in a particular place at the same time.
What is a habitat?
A place where a community of organisms lives.
What is a micro habitat?
Within each habitat there are smaller units, each with their own microclimate.
What is an ecological niche?
Describes how am organism fits into the environment refers to where an organism lives and what it does there. No two species occupy the same niche.
What is the equation for population growth?
(Births + immigration) - (deaths + emigration)
What is the equation for percentage population growth rate?
(Population change during period / population change at start of period) x100
What is the equation for birth rate?
(Number of births per year / total population in same year) x1000
What is the equation for death rate?
(Number of deaths per year / total population in same year) x 1000
What is average life expectancy?
The age at which 50% of the individuals in a particular population are still alive.
What is a population?
A group of interbreeding organisms of one species in a habitat.
What is frequency?
The likelihood of a particular species occurring in a quadrat.
What is abundance?
The number of individuals of a species within a given space.
What is percentage cover?
The measure of the proportion of ground in the area being studied that is covered by a particular species of plant.
What is the equation for mark-release-recapture?
Estimated population size = (individuals in first sample X individuals in second sample) / number of marked individuals recaptured
What are abiotic factors?
An ecological factor that is concerned with the non living part of the environment. E.g. Rainfall, soil pH, temperature.
What are biotic factors?
An ecological factor that is concerned with the activities of living organisms. E.g. Predation, food availability, competition.
What is intraspecific competition?
Individuals of the same species compete with one another for resources such as food, water, breeding sites.
What is interspecific competition?
Individuals of different species compete for resources such as food, light, water.
What is predation?
When one organism is consumed by another,
What is immigration?
Individuals join a population from the outside.
What is emmigration?
Individuals leave a population.
What is birth rate?
The number of children born each year per thousand if the population.
What is death rate?
The number of deaths each year per thousand of the population.
