Population Ecology
Energy Transfer
Keystone Species
Nutrient Cycles
100
What is carrying capacity?
The maximum number of individuals an environment can support.
100
Which trophic level has the most biomass?
producers
100
What is a trophic cascade?
A spiral of indirect effects from removing an apex predator form an ecosystem.
100
Why is nitrogen a necessary nutrient to cycle?
Element found in macromolecules like proteins and nucleic acids which allow organisms to grow and develop.
200
What is the difference between logistic and exponential growth?
Exponential growth is rapid population growth du to limited resources. Logistic growth reaches a carrying capacity due to limited resources.
200
Which trophic level would have the most energy?
Producers
200
What is a keystone species?
Species that maintains stability in the ecosystem.
200
What form of nitrogen cannot be used by plants and animals?
Atmospheric nitrogen or N2 gas.
300
What is the difference between density independent and density dependent limiting growth factors?
Density dependent limiting growth factors limit growth when the population gets too large and density dependent limiting growth factors limit growth regardless of population size.
300
How much energy is transferred between trophic levels?
10%
300
Which individual in the food web would you predict is the keystone species and why?
The wolf because they are the apex predator controlling the population size of many other species in the food web.
300
What is the role of bacteria in the nitrogen cycle?
Nitrogen fixation- converting N2 gas to usable forms like ammonia
400
What are examples of density dependent limiting growth factors?
Availability of space, mates, food, shelter
Predator vs prey and disease
400
What is bioaccumulation/biomagnification?
concentration of toxins increase as you move up the food chain.
400
How does the sea otter indirectly impact the kelp population?
Kelp--> sea urchin --> sea otter
Sea otters control the sea urchin population. Without otters the urchin overgraze the kelp.
400
How do humans impact the carbon cycle?
Excessive use of fossil fuels increases atmospheric carbon dioxide.
Farming practices add extra atmospheric CO2
Deforestation/urbanization increase atmospheric CO2
500
A bacteria population is cultured on a petri dish with a nutrient medium to help the grow. The population demonstrates exponential growth.
What will the population run out of that will limit their growth?
space
500
Which trophic level would you expect to have the greatest concentration of DDT, an insecticide, from the food chain below?
Krill-->Minnow-->Tuna-->Osprey
Osprey
500
How would the removal of sea otters affect levels atmospheric carbon dioxide?
Kelp--> sea urchin --> sea otter
No otters= no kelp= more CO2 in the atmosphere
500
How do humans impact the nitrogen cycle?
Excess nutrients in water due to fertilizer run off