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Course: Middle school biology - NGSS > Unit 4
Lesson 1: Populations, communities, and ecosystemsPopulations, communities, and ecosystems
Review your understanding of populations, communities, and ecosystems in this free article aligned to NGSS standards.
Key points:
- Populations and communities are groups of organisms.
- A population is a group of the same species living in the same area.
- A community is a group of different species living in the same area.
- An ecosystem is all of the organisms in an area plus the nonliving parts of their environment.
- Organisms interact with both living and nonliving parts of their ecosystem. Organisms depend on these interactions in order to survive and have offspring.
Want to join the conversation?
- what came first the egg or chicken?(53 votes)
- A circle has no beginning.(86 votes)
- how is all the population stick together(14 votes)
- because they are the same species.(14 votes)
- did you know that there is a kind of desert rat that does not drink water and it would die if it did(8 votes)
- To be clear, they actually do need water, just very little of it. They also don't 'drink' it most of the time they get water from other sources like the food they eat, the air, and more (but they will drink water if they find it) . Also, they will not die if they drink it.(8 votes)
- I still don't get the difference of a community and a population. they seem very alike to me(5 votes)
- A population is one species of animal, for example a population of fish. A community has multiple populations in one ecosystem. like a population of fish, and a population of sharks.(8 votes)
- DO BACTERIA COUNT AS A POPULATION? Or if there are only different bacteria, like on your hand, does that count as a community?(5 votes)
- Sure. An ecosystem, however, needs to have nonliving components to it as well.(3 votes)
- What happen if a Living thing does not have water.(3 votes)
- It would die because water is a vital part of every living things life(7 votes)
- how many things can a ecostyem get befpre there is too many animals or objects in it?(2 votes)
- This is an interesting question...... I think it would depend on the ecosystem itself and how populated it was. For example, if there were a desert with a lot of animals in it then most of them wouldn't last long. There just wouldn't be enough food to go around.(7 votes)
- Is a ecosystem a ecosystem when there is no animals or plants there?(3 votes)
- My guess would be yes. Consider a large, flat area made of stone. Or a lava-spewing volcano. I would consider it an ecosystem. Although in both of these cases, I don't think there could possibly be NO life at all, there's probably microorganisms somewhere in each of these environments.(5 votes)
- this is not biology this is english why are they just feeding us definitions and saying its biology sure it may be slightly related to biology but this is literally just definitions(4 votes)
- we invent concepts to not have to keep making sense of the same things over and over again(4 votes)
- what would happen if you where in a room filled with oxygen but none of the molecules are combined?(5 votes)