6th Grade Science Unit 9 Review 2025

Which of the following is a biotic factor in an ecosystem?

• Water

• Sunlight

• Grass

• Soil

What is the term for a relationship where both organisms benefit?

• Parasitism

• Mutualism

• Commensalism

• Competition

Which of the following is the correct order of organization in an ecosystem from smallest to largest?

• Community, organism, population

• Organism, population, community

• Population, community, organism

• Organism, community, population

A population of rabbits has some individuals with white fur and some with brown fur. If the environment becomes snowy, which fur color is likely to be an advantage?

• Brown fur

• White fur

• Both colors

• Neither color

Which of the following is an abiotic factor that organisms in a pond ecosystem might compete for?

• Fish

• Algae

• Sunlight

• Frogs

Which relationship describes a tick feeding on a dog?

• Mutualism

• Parasitism

• Commensalism

• Competition

A group of the same species living in the same area is called a:

• Community

• Population

• Ecosystem

• Organism

Which of the following is an example of a variation within a population?

• All birds in a flock have the same beak size

• Some fish in a pond are larger than others

• All trees in a forest are the same height

• All wolves in a pack have the same fur color

If two different species of birds eat the same type of insect, what type of relationship is this?

• Predatory

• Competitive

• Mutualistic

• Parasitic

Which of the following best describes a community in an ecosystem?

• All the abiotic factors in an area

• All the populations of different species in an area

• All the organisms of one species in an area

• All the plants in an area