earth systems

Question 1

the earth as a planet is

Answer 1

closed system

Question 2

gaseous layer above the earth’s surface

Answer 2

atmosphere

Question 3

consists of mixtures of gases

Answer 3

atmosphere

Question 4

regulates climate

Answer 4

atmosphere

Question 5

consists of all forms of life on earth

Answer 5

biosphere

Question 6

the only thin layer at the earth’s surface

Answer 6

biosphere

Question 7

include all the water on our planet

Answer 7

hydrosphere

Question 8

what percent of the earth is covered in water

Answer 8

75

Question 9

what percent of the water is in the oceans

Answer 9

97

Question 10

what percent of the water is fresh

Answer 10

3

Question 11

solid earth

Answer 11

geosphere

Question 12

composed of iron and nickel

Answer 12

core

Question 13

in solid form because of great pressure

Answer 13

inner core

Question 14

liquid and sea of molten metal

Answer 14

outer core

Question 15

what varies the physical characteristics of the manthe

Answer 15

depth

Question 16

cool, strong, and hard, with a relatively low pressure

Answer 16

outer mantle

Question 17

outermost layer

Answer 17

crust

Question 18

upper layers of regolith

Answer 18

soil

Question 19

layer of loose fragments, clay, and sand

Answer 19

regolith

Question 20

fine-grained and closely-packed

Answer 20

clay

Question 21

loosely-grained

Answer 21

sandy soil

Question 22

decomposed litter; readily soaks moisture

Answer 22

humus

Question 23

uppermost layer of the soil that contains litter, humus, and minerals

Answer 23

o horizon

Question 24

humus, sand, silt, and clay

Answer 24

a horizon

Question 25

transitional zone where roots and other organic material grow

Answer 25

b horizon

Question 26

consists of partially weathered rock and little organic matter

Answer 26

c horizon

Question 27

solid rock

Answer 27

bedrock

Question 28

degradation of topsoil due to farming

Answer 28

agricultural depletion

Question 29

tilting of soil

Answer 29

loosens it

Question 30

help maintain the soil

Answer 30

planting cover crops

Question 31

planting of different crops in the same soil will help return nutrients to soil

Answer 31

crop rotation

Question 32

greatly increases the rate of soil erosion

Answer 32

overgrazing animals

Question 33

large amounts of earth were upheaved

Answer 33

mining operations

Question 34

large amounts of soil are exposed

Answer 34

mining operations

Question 35

soil erosion could be promoted by urban and suburban development

Answer 35

development/expansion

Question 36

human activities can cause soil erosion

Answer 36

recreational activities

Question 37

bare spots may develop from hiking trails

Answer 37

recreational activities