Basics of Ecology
What is a population?
A group of individuals from the same species in the same area
What is a community?
all the species in an area
What does an ecosystem include that neither a population or a community have?
abiotic factors (nonliving things)
Name at least three different biomes.
Tropical forest, savanna, desert, chaparral, temperate grassland, deciduous forest, boreal forest, tundra, etc
What is population density?
the number of individuals per unit area (on land) or per unit volume (in water or the atmosphere)
What are two of the five interspecific interactions?
1. Coevolution
2. Competition
3. Predation
4. Herbivory
5. Symbiosis
What are four trophic levels?
1. Producers (mainly plants)
2. Primary consumers (mainly herbivores)
3. Secondary consumers (eats herbivores)
4. Tertiary consumers (eats secondary consumers)
What is a carrying capacity?
max population size an area can hold due to resources
What is at least two examples if abiotic factors that affect most communities?
Water, wind, fire, temps, sunlight, soil, etc
What are the three types of population dispersion?
1. Clumped
2. Uniform
3. Random
What are the three types of symbiosis?
1. Commensalism
2. Mutualism
3. Parasitism
Where does the energy for all trophic levels originate from?
the sun
As you go up each tropic level, what form energy lost as?
heat
Why do different latitudes have different climates?
Angle of sunlight hitting the surface of the earth varies at different latitudes. Equator has most direct sunlight, while the poles have the least direct sunlight.
Explain at least of the three survivorship curves.
Type 1 - low early death rate, high late death rate
Type 2 - constant death rate throughout all life stages
Type 3 - high early death rate, low late death rate
What is a keystone species?
a species that holds together a community; might be main food source and/or predator in the community
What is productivity in an ecosystem?
amount of life an ecosystem supports
As you go up each trophic level, how much energy is lost at each level?
90%
What are the two types of population growth?
1. exponential (j-shape) - population grows without limits
2. logistic (s-shape) - population grows until it hits carrying capacity (k) then stays constant
Describe both primary and secondary succession.
Primary - new life grows where life hasn't been
Secondary - event happens that eliminates previous life and a recovery period happens that either brings new life or regrows previous life
What is biological magnification?
When a toxin is consumed at lower trophic levels and then is passed through a food chain to higher trophic levels and concentrations of the toxin add up as you go up those trophic levels.
What is the greenhouse effect?
CO2 being released into the atmosphere and then getting trapped and heating up the earth