When scientists are doing research to determine how the environment affects a life form, it often takes many years to reach a conclusion. Why do you think that is the case?
a.
Many environmental factors must be considered (water, light, and temperature were just three that were investigated in this simulation).
b.
Many tests must be performed because variables need to be tested one at a time (first test for water effects, then test for light effects, etc.).
c.
Some effects take a long time to become noticed, so the experiments often have to take place over long periods of time.
d.
All of the above.

Please select the best answer from the choices provided

A
B
C
D

Hummingbirds drink nectar from flowers, while robins eat plant seeds. what does this reduce?

1. emigration the movement of people from one place to another 2. immigration a situation in which resources are being used up at a faster rate than they can be replenished 3. migration the leaving of one's homeland to settle in a new place 4. overpopulation the movement of people to a new country 5. sustainable development a situation in which the birth rate is not sufficient to replace the existing population 6. underpopulation the ability to meet current needs without reducing the ability to meet future needs 7. unsustainable development the increase in the population of a city 8. urbanization a situation in which the number of people exceeds the available natural resources in an area

Agroup of plant cells was exposed to radiation, which damaged the chloroplasts and caused them to lose function. if the mitochondria were unharmed, what would happen to the overall function of the plant cells? a. the cells would not be able to make food, but would be able to release energy from biomolecules. b. the cells would not be able to replicate dna, but would be able to break down waste. c. the cells would not be able to break down waste, but would be able to replicate dna. d. the cells would not be able to release energy from biomolecules, but would be able to make food.