Community Ecology
Describe a trophic cascade.
A trophic cascade shows the presence or absence of a predator at the top of the food chain and the ripple effects it causes on other species and populations.
What is the formula for population growth?
dN/dt=B-D
What is an endothermic organism?
An organism that can regulate its body temperature.
Describe a producer.
Explain adaptations.
the action or process of adapting or being adapted
List the different symbiotic relationships.
Parasitism, Competition, Commensalism, Mutualism.
Describe the difference between logistic and exponential growth.
Logistic growth: The population reaches its carrying capacity and then stabilizes due to limited resources.
Exponential growth: The population will increase rapidly as time increases.
What is the function of an autotroph?
To produce their food from sunlight or chemical reactions.
What is a keystone species?
Describe different ways invasive species can enter an ecosystem.
Pest control, accidental introduction through shipping, agriculture.
What is the concept of niche partitioning?
A process where multiple species coexist by dividing resources in a way that minimizes competition.
If a river has a population of 800 fish at the beginning of the year, and 160 newborn fish are born, what is the birth rate?
160/800
Birth rate = 0.2
Name and explain the statement that describes energy transfer through consumers in an energy pyramid.
The 10% rule. 10% of energy is transferred between consumers.
Describe essential biotic factors.
Living organisims in the enviornment and their interactions
Where do mutations come from?
Mutations can come from internal factors within the cell or outside environmental influences.
What are ways in which cooperation between species can result in enhanced movement of access to matter and energy?
Competition, Predation, Parasitism, Mutualism, Commensalism
How do photosynthetic organisms capture energy?
Through photosynthesis.
Name ways diversity can influence the organization of ecosystems.
(at least 2 ways)
Stability and Resilience
Energy Flow and Nutrient Cycling
Productivity
What are the effects of human activities on habitats?
Habitat fragmentation, degradation, and destruction
Describe a predator/prey relationship.
1,200 foxes live in a wooded area. Over 1 year, 60 died and 180 were born. Determine the new population size at the end of the year.
There will be 1,320 foxes in the woods at the end of the year.
Explain the effect of a change in the producer level on the number and size of other trophic levels.
If producers decrease, primary consumers will have lower survival and reproduction, and the population will decline. If producers increase, more energy will be available at the base of the trophic levels, and higher trophic levels may increase in number and size.
Ways keystone species, producers, and essential biotic/abiotic factors maintain the diversity of an ecosystem.
Keystone species: regulate populations, create/modify habitats, facilitate species coexistence.
Producers: base of the food web, creation of habitats, involved in nutrient cycling.
biotic/abiotic factors: promote species richness, stabilize ecosystems
How are mutations random with no direction for selective pressure?
Mutations occur without considering their usefulness.