This Column
Every trophic level has a "job". What is the job of decomposers?
a. return nutrients to soil
b. eat dead organisms
c. turn CO2 into oxygen
d. keep consumer populations low
a. return nutrients to soil
What is the word for a population that is moved to an ecosystem, but is not from that area.
Introduced species
What happens to a population of oysters when the rocks they stick to are occupied.
The population dies off because it does not have a habitat
What is the independent variable?
What is the dependent variable?
Independent Variable: Time on Social Media
Dependent Variable: Less books read
How do you determine the biodiversity index for an ecosystem?
A) The number of all the organisms in an area divided by the size of the area
B) The total species divided by total individuals
C) The total organisms divided by total species
D) The number of species in an area divided by the number of samples
B) The total species divided by total individuals
Hippos eat water hyacinths. Explain what would happen to the population of water hyacinths if the hippo population tripled.
The water hyacinths population would decrease.
What is the word for a population that is moved to an ecosystem, and is so successful that it changes the balance of that ecosystem?
Invasive species
Why was the video about Hawaii titled: Strangers in Paradise?
Because all of the native species evolved from introduced species
Which question would be the best high level scientific question?
A) How many giraffes live in Africa?
B) Who made the first microscope?
C) How long ago did dinosaurs live on the Earth?
D) Does the amount of salt in water affect the temperature at which it boils?
D) Does the amount of salt in water affect the temperature at which it boils?
A scientist who wants to study the affects of fertilizer on plants sets up an experiment. Plant A gets no fertilizer, Plant B gets 5 mg. of fertilizer each day, and Plant C gets 10mg. of fertilizer each day. Which plant is the control group.
A) Plant B
B) All of them
C) Plant A
D) Plant C
C) Plant A
Imagine an ecosystem with two tertiary consumers: bears and wolves. They both eat the same food sources.
What would happen if the wolf population doubled?
The wolves would consume most of the food sources, which would give less food for the bears. That may reduce the bear population. It may also reduce the populations of secondary consumers.
California Gulls consume insects in an ecosystem in Washington State (about 800 miles from Mono Lake).
What could happen to the coyotes in Mono Lake if that population of insects becomes extinct?
The birds would have less to eat, which would lower the Gull population. That would give the coyotes less to eat, and lower the coyote population.
Why was the carnivorous caterpillar so vulnerable to ants?
The caterpillar did not evolve with a defense for the invasive ants.
A scientist conducted an experiment to determine how the amount of salt in a body of water affects the number of plants that can live in the water. In this experiment the dependent variable is
A) the temperature of the water
B) the number of plants in the water
C) the water
D) the amount of salt in the water
B) the number of plants in the water
What skill is a scientist using when she listens to the sounds that whales makes.
A) making a hypothesis
B) drawing conclusions
C) interpreting data
D) making observations
D) making observations
Explain how many of each population would be sustainable for these organisms in Yellowstone National Park, and what trophic level they are in: wolves, grasses, rabbits, foxes, deer
More grass, some deer and rabbits, very few wolves and foxes.
Producers: grass
primary consumers: deer and rabbits
secondary consumers: foxes
tertiary consumers: wolves
How would building an amusement park in the swamps of Orlando Florida affect the environment?
It would take away habitat for hunting, reproducing, and shelter.
No plants in Hawaii have evolved with thorns or poisons. How does this put them in danger?
Humans have introduced cattle, pigs, and goats. These animals can graze on all of the native plants.
Workers at a company were assigned to one of two conditions: One group completed a stress management training program; another group of workers did not participate in the training. The number of sick days taken by these workers was examined for the next 2 months.
Find the independent and dependent variables
Independent Variable: Stress Management Training
Dependent Variable: Sick days taken
A species that occurs in the region in which it evolved is called:
a. An invasive species
b. A natural species
c. A native species
d. An exotic species
c. A native species
Which of the following is an abiotic cause for a population to increase.
a. A bacteria spread on an island where sea turtles lay their eggs
b. increased rainfall in an area with many trees
c. decreased rainfall in an area with many trees
d. a tsunami destroyed the coast where sea turtles lay their eggs
b. increased rainfall in an area with many trees
What are ecosystem services?
Things from an ecosystem which humans benefit from
It may become invasive, and unbalance the ecosystem.
Students at a University were split into two groups and each received a different text for a philosophy course. Once group received a traditional text book, while the other received an interactive textbook on a tablet computer. After the course, the final exam grades between the two groups of students was compared.
Find the independent variable and dependent variable
Independent Variable: Type of book used in college class
Dependent Variable: Final exam grade
Zebra mussels, an invasive species that is pushing local species of freshwater shellfish to extinction, were introduced to the Great Lakes by:
a. Migrating Native Americans
b. Teenagers playing a prank
c. Ballast water (sea water that ships carry for stability and then discharge)
d. None of the above
c. Ballast water (sea water that ships carry for stability and then discharge)