S3U4L1 - Ecosystems and Interactions Part 2

S3U4L1 - Ecosystems and Interactions

Part 2

Land Habitats

In what ways are deserts and tundra alike and different from each other?

• Deserts and tundra are alike because they are both very dry. Neither of them gets very much rain. Also, both deserts and tundra provide harsh conditions for the plants and animals that live there.

• There are differences between the two. The tundra is much colder than a desert and parts of it stay frozen all year long.

• Deserts experience extreme temperature changes: sometimes they are very hot, and sometimes they become very cold. 

Because a desert is so dry, how do plants get the water they need to survive?

• Many desert plants store water to use when the weather is dry.

• Some desert plants have shallow roots that can quickly absorb rainwater.

• Some desert plants only appear after it rains.

Why would the rain a rain forest gets every day make the air feel sticky and damp?

• When it rains, the air takes up water vapor.

• It rains so much in a rain forest that there is a lot of water in the air.

• When the air is holding nearly all the water it can hold, we can feel it on our skin as dampness or stickiness.

• This is called humidity.

Multiple Select

Do camels store water in their humps?

• Yes

• No

• No, camels do not store water in their humps. A camel’s hump is made of fat. .

• When food is scarce, a camel’s body can use the fat as a source of energy so that the camel can do without food for weeks.

• Camels are just very good at surviving without water for long periods

Multiple Select

If a population of barn owls feeds on deer mice, are the owls and the mice part of the same population or part of the same community?

• part of the same population

• part of the same community

The owls and the mice are two different populations within the same community.

Multiple Select

A white-tailed deer is drinking from a pond. Is the pond part of the deer’s habitat or part of the deer’s community?

• part of the deer's habitat

• part of the deer's community

The pond is part of the deer’s habitat.

A community is made of populations of different organisms all living in the same area.

A habitat is an area where an organism lives.

Water Habitats

Sea otters wrap themselves in kelp when they fall asleep floating on the ocean surface. Why do you think they do this?

• Kelp is rooted on the ocean floor.

• Sea otters wrap themselves in kelp so that they don’t float too far out into the ocean.

• Otherwise, they might wake up to find themselves lost in deep waters far from home!

Multiple Choice

Can you think of another freshwater habitat that, like a pond, is completely surrounded by land?

• lake

• ocean

• pond

• river

A lake is completely surrounded by land. Most lakes are freshwater. Lakes tend to be larger than ponds and have areas of deeper water.

Why do you think that the part of a river close to the ocean is wider than the part of a river close to the mountains?

• By the time a river nears the ocean, many streams and other rivers have flowed into it on their way to the ocean.

• Each stream adds more water to the river and increases erosion, so the river is wider.

Why do you think that wetlands can be found at the edges of some ponds, rivers, or the ocean?

• Wetlands are drier than ponds, rivers, and the ocean but wetter than dry land.

• Wetlands are an area of transition between a body of water and the land that borders it. 

What are some reasons wetlands are important to Earth?

• Wetlands help clean water by filtering dirt and pollution out of it.

• They also help control flooding. When there is too much water in an area, wetlands act like a sponge and absorb the extra water.

• The roots of wetland plants prevent erosion by trapping soil so that it is not carried away by flowing water.

end of today's presentation

to be continued