the water cycle


Most precipitation that occurs over land, however, is not absorbed by the soil and is called runoff. This runoff collects in streams and rivers and eventually flows back into the ocean.

the water cycle

Whereas energy flows through an ecosystem, water and elements like carbon and nitrogen are recycled. Water and nutrients are constantly being recycled through the environment. This process through which water or a chemical element is continuously recycled in an ecosystem is called a biogeochemical cycle. This recycling process involves both the living organisms (biotic components) and nonliving things (abiotic factors) in the ecosystem. Through biogeochemical cycles, water and other chemical elements are constantly being passed through living organisms to non-living matter and back again, over and over. Three important biogeochemical cycles are the water cycle, carbon cycle, and nitrogen cycle. The biogeochemical cycle that recycles water is the water cycle. The water cycle involves a series of interconnected pathways involving both the biotic and abiotic components of the biosphere. Water is obviously an extremely important aspect of every ecosystem. Life cannot exist without water. Many organisms contain a large amount of water in their bodies, and many live in water, so the water cycle is essential to life on Earth. Water continuously moves between living organisms, such as plants, and non-living things, such as clouds, rivers, and oceans ( Figure The water cycle does not have a real starting or ending point. It is an endless recycling process that involves the oceans, lakes and other bodies of water, as well as the land surfaces and the atmosphere. The steps in the water cycle are as follows, starting with the water in the oceans: 1. Water evaporates from the surface of the oceans, leaving behind salts. As the water vapor rises, it collects and is stored in clouds. 2. As water cools in the clouds, condensation occurs. Condensation is when gases turn back into liquids. 3. Condensation creates precipitation. Precipitation includes rain, snow, hail, and sleet. The precipitation allows the water to return again to the Earths surface. 4. When precipitation lands on land, the water can sink into the ground to become part of our underground water reserves, also known as groundwater. Much of this underground water is stored in aquifers, which are porous layers of rock that can hold water.


Water also moves through the living organisms in an ecosystem. Plants soak up large amounts of water through their roots. The water then moves up the plant and evaporates from the leaves in a process called transpiration. The process of transpiration, like evaporation, returns water back into the atmosphere.

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the water cycle recycles water through both the living and non-living parts of an ecosystem.

-->  a. true

b. false

the water cycle always starts with water evaporating from the ocean or lakes.

a. true

-->  b. false

what is the process in which water evaporates from leaves?

a) condensation

b) precipitation

c) evaporation

-->  d) transpiration

what process allows water to return to the earths surface?

a) condensation

-->  b) precipitation

c) evaporation

d) transpiration

which of the following is in the correct order?

-->  a) precipitation  runoff  streams/rivers  oceans  evaporation

b) precipitation  runoff  groundwater  oceans  evaporation

c) precipitation  runoff  aquifer  oceans  evaporation

d) transpiration  runoff  streams/rivers  aquifers  evaporation

evaporation produces

a) precipitation.

b) rain or snow.

-->  c) water vapor.

d) condensation.

rain, snow, hail, and sleet are examples of

-->  a) precipitation.

b) condensation.

c) evaporation.

d) bad weather.

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