What would best explain the decrease in primary producers?

• an increase in solar energy
• a decrease in O2 levels in the H2O
• a decrease in the population of tertiary consumers
• an increase in the population of primary consumers

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

What would likely be the result if a pesticide is used to reduce the # of harvester ants?

• an increase in snakes & a decrease in hawks
• a decrease in snakes & an increase in hawks
• a decrease in mesquite bushes & an icnrease in horned lizards
• an increase in mesquite bushes & a decrease in horned lizards

Pond ecosystems require N, P, and K in order to support the growth of algae.  This increase in algal growth can cause an increase in decaying matter in the pond.  What LONG-TERM effect might an increase in algal growth have on a pond ecosystem?

• a decrease in the amount of available O2 necessary for fish in the ecosystem
• an increase of the fish population in the pond
• a population increase in other producers, such as water lilies, in the ecosystem
• an increase in available food for the fish in the ecosystem

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

NGSS.MS-LS2-4

Human-built dams across rivers have both positive & negative effects on the environment.  What effect does building dams have on environments downstream?

• a positive effect due to increasing the natural flow of nutrients
• a negative effect due to reducing populations of non-native species
• a negative effect due to increasing the populations of native species
• a negative effect due to decreasing the natural flow of nutrients

Tags

NGSS.MS-LS2-4

NGSS.MS-LS2-5

Coral reefs are important to many ocean ecosystems because they provide food & shelter for numerous marine organisms.  Climate changes that lead to increased water temperatures can slow the growth of coral.  Scientists monitor the physical conditions & species distribution of coral reefs & try to temporarily alter conditions when they are harmful to coral reefs.  Which of these actions would BEST accomplish the goal of preserving coral reefs?

• restrict regulations concerning reefs
• isolate predators from reef inhabitants
• protect the biodiversity of coral reefs
• identify new species associated with reefs

Tags

NGSS.MS-LS2-4

NGSS.MS-LS2-5

The oak savanna ecosystem is dependent on wildfires & controlled burnings to manage the growth of invasive & nonnative shrubs and trees and to help maintain the native semi-open ecosystem.  Which statement BEST describes the impact invasive plant species could have if not maintained by fires?

• they could decrease the populations of native species
• they could decrease the amount of O2 available for the native animals
• they could increase the amount of food available to native plants & animals
• they could increase the amount of N in the soil that is toxic to the native plants

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

Which factor is responsible for beginning the process of change in the ecosystem from diagram 1 to 4?

• climate change in the area
• breakdown of rock for more P in the area
• organic matter from producers
• action of roots by large trees in the area

Which of these factors is most important for reestablishing plants & trees on an abandoned farm?

• sunlight & CO2
• O2 and CO2
• glucose & N
• ATP and xylem

Tags

NGSS.MS-LS1-6

A decrease in the frog population would MOST likely lead to an increase in the population of which organisms?

• owl
• grass
• snake
• grasshopper

How would a drought in the Southern Plains most likely affect the quail population?

• an increase in the quail population due to a decrease in the rabbit population
• a decrease in the quail population due to a decrease in nesting cover
• an increse in the quail population due to a decrese in the mouse population
• all of these