apes unit 3

Question 1

types of soil horizon

Answer 1

O, A, B, C, R

Question 2

o horizon

Answer 2

leaf litter, organic material

Question 3

a horizon

Answer 3

plough zone, rich in organic matter

Question 4

b horizon

Answer 4

zone of accumulation

Question 5

c horizon

Answer 5

weathering soil, little organic material or life

Question 6

r horizon

Answer 6

unweathered parent material

Question 7

chemical weathering

Answer 7

chemical weathering occurs when reactions between a rock and another substance change the chemical composition of the rock.

Question 8

physical weathering

Answer 8

Physical weathering is when a rocks composition is physically changed by another substance

Question 9

biological weathering

Answer 9

Biological weathering is the weakening and subsequent disintegration of rock by plants, animals and microbes

Question 10

physical weathering examples

Answer 10

thermal expansion: rock expands when exposed to heat
abrasion: rocks scratching and rubbing against each other causing breakage
frost wedging: constant freezing and thawing of rock

Question 11

chemical weathering examples

Answer 11

oxidation: rock breaks bc of exposure to oxygen
hydrolysis: combines acidic water and rocks and forms clay and salt
carbonation: water and co2 make carbonic acid which breaks down rocks

Question 12

biological weathering examples

Answer 12

burrowing animals: animals dig in the soil to burrow causing surrounding rocks to break or damage
organic material: the byproduct of plant and animal decomposition, added to soil and to minerals in rocks
lichens: lichens like algae and fungus produce acid that causes rocks to break down when in contact with it

Question 13

nitrogen fixation

Answer 13

when nitrogen is converted to ammonia

Question 14

nitrification

Answer 14

ammonia converted to nitrites and nitrates

Question 15

ammonificiation

Answer 15

bacteria breaks down nitrogen chemicals from dead matter into ammonia

Question 16

assimilation

Answer 16

incorporating nitrates into plant roots

Question 17

dentrification

Answer 17

nitrites and nitrated converted to gaseous nitrate and nitrogen