Biomes are major communities of ecosystems grouped together based on vegetation and climate similarities.

The permanently frozen layer of soil is called permafrost.

Animals need to be adapted to the cold, harsh weather. This means they have thick fur or hollow hair.

Most plants are small because of the permafrost. The soil is so frozen that roots can't penetrate very deep. That means no large trees.

This biome is characterized by tall coniferous (evergreen) trees. They rarely shed their needles and provide cover all year.

Animals need to be adapted to cold temperatures and snow for a large portion of the year.

Coniferous trees are pine trees. They are green all year and rarely drop their needles. They are tall and provide lots of ground cover.

The temperate forest has four distinct seasons determined by the climate. These seasons are winter, spring, summer, and fall.

The animals need to be adapted to changes in weather and possibly food sources as a result.

Deciduous trees drop their leaves in the fall as a result of changing climate. The leaves regrow in the spring.

Deserts are dry biomes. The annual rate of evaporation exceeds the rate of precipitation.

Animals need to be adapted to hot, dry weather. A lot of them are nocturnal due to the heat.

Plants need to be adapted to dry climates as well. Most are succulents, which means they hold water (due to thick cuticles) so that they can use it slowly to prevent evaporation.

The tropical rain forest is an area with warm, humid temperatures. It is characterized by very tall trees that create a canopy (roof) over the area below.

Many of the animals that live in the rain forest actually live in the trees. Even the tribes that live in the rain forest often build their "houses" in the trees.

Plants in the rainforest are tropical and need to be adapted to the warm, humid climate. Most are a food source or habitat source for the animals that live there.

Grasslands can be tropical or temperate. Tropical grasslands are called the savanna and are found in Africa. Temperate grasslands are often called the prairie and are found in the middle of the United States.

Animals that live in the grasslands are often herbivores and feed on the grass. In the savanna, there are also top predators like lions that feed on the herbivores.

The grassland is dominated by grass. The grass has a large root system that helps it to regrow after a fire (fires are common).