Why do organisms cannot survive alone

On the worksheet have the students identify whether the picture is an individual, a population, a community, or an ecosystem. If you have coloring books on different animal or plant communities and individuals you may want each child to do a different picture and have them hang then up under a sign that says Individuals, Populations, Community, and Ecosystems.

We suggest that the students number a sheet of blank paper and list the answers, so you can re-use the sheet. The answers are: Individuals 1,3 ; Populations 2,7 ; Community 4,5 ; Ecosystems 6. Comparing individuals, populations, communities, and ecosystems. Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. Freshwater is a precious resource on the Earth's surface.

It is also home to many diverse fish, plant, and crustacean species. The habitats that freshwater ecosystems provide consist of lakes, rivers, ponds, wetlands, streams, and springs. Use these classroom resources to help students explore and learn about these places. A limiting factor is anything that constrains a population's size and slows or stops it from growing. Some examples of limiting factors are biotic, like food, mates, and competition with other organisms for resources.

Others are abiotic, like space, temperature, altitude, and amount of sunlight available in an environment. Limiting factors are usually expressed as a lack of a particular resource. For example, if there are not enough prey animals in a forest to feed a large population of predators, then food becomes a limiting factor. Likewise, if there is not enough space in a pond for a large number of fish, then space becomes a limiting factor.

There can be many different limiting factors at work in a single habitat, and the same limiting factors can affect the populations of both plant and animal species.

Ultimately, limiting factors determine a habitat's carrying capacity, which is the maximum size of the population it can support. Teach your students about limiting factors with this curated collection of resources. A biome is an area classified according to the species that live in that location. Temperature range, soil type, and the amount of light and water are unique to a particular place and form the niches for specific species allowing scientists to define the biome.

However, scientists disagree on how many biomes exist. Some count six forest, grassland, freshwater, marine, desert, and tundra , others eight separating two types of forests and adding tropical savannah , and still others are more specific and count as many as 11 biomes. Use these resources to teach middle school students about biomes around the world. A biotic factor is a living organism that shapes its environment.

In a freshwater ecosystem, examples might include aquatic plants, fish, amphibians, and algae. Biotic and abiotic factors work together to create a unique ecosystem. Learn more about biotic factors with this curated resource collection. A habitat is an environment where an organism lives throughout the year or for shorter periods of time to find a mate.

The habitat contains all an animal needs to survive such as food and shelter. A microhabitat is a small area which differs somehow from the surrounding habitat.

Its unique conditions may be home to unique species that may not be found in the larger region. Unfortunately, some habitats are threatened by pollution, extreme weather, or deforestation. This puts many of the species that live there in danger and is causing many populations to decline.

Explore different types of habitats and microhabitats with this curated collection of classroom resources. The species population size is limited by environmental factors like adequate food, shelter, water, and mates. If these needs are not met, the population will decrease until the resource rebounds. Explore carrying capacity with these curated classroom resources. Learn about the places animals live—from the grassland to the desert and the burrow to the hive.

Students brainstorm examples of familiar animals and their needs. They learn that a habitat satisfies the basic needs that must be met for an animal to survive.

Generalist species can feed on a wide variety of things and thrive in various environments. Specialist species eat a limited diet and occupy a much narrower niche. Join our community of educators and receive the latest information on National Geographic's resources for you and your students. Skip to content. Twitter Facebook Pinterest Google Classroom. Encyclopedic Entry Vocabulary.

An everyday example is that students think various lifecycle stages of a butterfly are not alive the eggs and immobile pupae , whereas a caterpillar and butterfly can move and are therefore considered to be alive. The students focus on the activity that takes place within a location. Most students list only vertebrates , particularly mammals as animals.

Some children think animals live only on land. It is common for year old students to have no conception of humans as animals. Living things may be distinguished from non-living things in their ability to carry on life processes such as movement, respiration, growth, responsiveness to environmental stimuli and reproduction. This view of living may be appropriate at this age but has some limitations and can lead to the alternative conceptions above.

For example movement in plants is not apparent to students and consequently they may not consider plants living. Decisions about whether things are alive or non-living remain problematic as not all life processes stop at the same time.

For example, human fingernails and hair continue to grow for weeks after death. To build up a concept of living things focus on the similarities shared with unlike living things.