Vocab
A system comprising biotic and abiotic factors of an environment
Ecosystem
The table provides information on population density of mayflies, a kind of insect, in a certain area over a few years. Estimated Population Density of Mayflies (1000 organisms/km2)
2005=2.9 2006=3.7 2007=3.6 2008=1.6
Based on the population density data provided, which data provides evidence that there was a significant increase in the population of birds that prey on mayflies?
A. 2005
B. 2006
C. 2007
D. 2008
D. 2008
Give an example of how plants compete with each other.
Plants can compete for things they need, such as water, space, nutrients, and sunlight
When two or more individuals or populations attempt to obtain a resource
Competitive Interaction
Which of the following would demonstrate an appropriate prediction for the changes to one of the populations of organisms due to a predator/prey interaction?
A. When the population of sharks decreases because of fishing, the population of small fish will decrease.
B. After a period of heavy rainfall and warmer temperatures, the population of mosquitos will increase.
C. During hunting season, when many deer are killed by hunters, the mountain lion population will decline.
D. When abundant resources allow the population of mice to increase, the population of snakes will decrease.
C. During hunting season, when many deer are killed by hunters, the mountain lion population will decline.
How does a parasitic relationship differ from a predatory relationship?
In predation, the animal hunts and kills the other animal. In parasitism the parasite does not usually kill its host.
An interaction that is helpful to both organisms
Mutually Beneficial Interaction
Certain bacteria live and grow on the roots of some plants, and produce chemicals that are beneficial to the plants. Which of the following observations best supports the claim that this relationship is beneficial to the plants?
A. When the bacteria are removed from the plant roots and are grown in a laboratory setting, the bacteria fail to survive.
B. The population size of the bacteria varies greatly depending on the chemistry of the soil and the type of the plant.
C. Plants with a higher density of the bacteria on their roots have increased rates of survival and reproduction.
D. The chemical produced by the bacteria can be created by humans and added to the soil where it reaches the roots of the plant.
C. Plants with a higher density of the bacteria on their roots have increased rates of survival and reproduction.
What role do decomposers play in an ecosystem?
Decomposers break down dead plants and animals, recycling nutrients back into the ecosystem.
Examples: fungi, bacteria, earthworms.
An interaction during which one animal eats another
Predatory Interaction
Symbiotic relationships can exist between the biotic and abiotic factors within an ecosystem or even between different ecosystems. Which of the following would best represent a relationship between these two factors?
A. Bird and tree
B. Dog and bone
C. Fish and water
D. Water and rocks
C. Fish and water
What is biodiversity, and why is it important for ecosystem stability?
Biodiversity is the variety of life in an area. It increases ecosystem resilience and helps maintain balance.
Need for systems to work together to accomplish various tasks
Interdependent
The table below shows four ecosystems and different examples of species interactions in each.
Ecosystem Examples
1: A bee pollinating a flower
2: A tapeworm living in the intestine of a cow
3: A clownfish living in the stinging tentacles of a sea anemone
4: A lion and cheetah hunting gazelles
Which of the following explanations best describes the relationships within these ecosystems?
A. Ecosystems 1 and 2 contain a predatory interactions
B. Ecosystems 1 and 3 contain a mutually beneficial interaction.
C. Ecosystems 3 and 4 contain a competitive interaction.
D. Ecosystems 2 and 4 contain a parasitic interaction.
B. Ecosystems 1 and 3 contain a mutually beneficial interaction.
How can human activity disrupt ecosystem relationships? Give one example.
Humans can disrupt ecosystems through pollution, habitat destruction, introducing invasive species, or overhunting.
Example: Deforestation removes habitats and upsets food chains.