Food Webs and Changes in Populations Quiz 24-25

A farmer had an accident and spilled a chemical into his pond. Several days later, he noticed many dead frogs around the pond. That summer, the number of flies around the pond was higher than ever. This is because

• the chemical doesn’t affect the populations of the pond

• the frogs are limiting factors for the flies

• the flies are a limiting factor for the frogs

• the chemical is a limiting factor for the flies

A scientist was studying a population of fish in a pond over a period of 10 years. He observed that the population increased each year for 3 years and then leveled off and stabilized for the rest of the study. The best explanation for this observation is that the population had

• No predators

• Limiting factors

• Abundant resources

• Natural hazards

These restrict populations from growing exponentially larger in ecosystems.

• carrying capacity

• limiting factor

• population density

• niche

The maximum number of organisms that an ecosystem can support is known as ________.

• changes in population

• population density

• energy pyramid

• carrying capacity

What happens to the population of an ecosystem if no limiting factors exist?

• population remains the same

• population decreases

• population increases

• population fluctuates

In the graph below where was the population growing the most?

• days 1-7

• days 9-17

• days 21-27

• days 29-35

What is the carrying capacity in the graph to the right?

• 500

• 1000

• 400

• 800

The growth rate of a population that has a limited food supply will MOST LIKELY be __.

• exponential

• natural

• logistic

• random

How many producers are in the food web?

• 3

• 2

• 1

• 0

How many carnivores in the food web?

• 0

• 1

• 2

• 3