Ch. 31 Soil and Plant Nutrition

Question 1

A horizon

Answer 1

consists of a mixture of organic material with inorganic products of weathering

Question 2

B horizon

Answer 2

soil layer that is an accumulation of mostly fine material that has moved downward

Question 3

bedrock

Answer 3

solid rock that lies beneath the soil

Question 4

C horizon

Answer 4

layer of soil that contains the parent material, and the organic and inorganic material that is broken down to form soil; also known as the soil base

Question 5

clay

Answer 5

soil particles that are less than 0.002 mm in diameter

Question 6

epiphyte

Answer 6

plant that grows on other plants but is not dependent upon other plants for nutrition

Question 7

horizon

Answer 7

soil layer with distinct physical and chemical properties, which differs from other layers depending on how and when it was formed

Question 8

humus

Answer 8

organic material of soil; made up of microorganisms, dead animals and plants in varying stages of decay

Question 9

inorganic compound

Answer 9

chemical compound that does not contain carbon; it is not part of or produced by a living organism

Question 10

insectivorous plant

Answer 10

plant that has specialized leaves to attract and digest insects

Question 11

loam

Answer 11

soil that has no dominant particle size

Question 12

macronutrient

Answer 12

nutrient that is required in large amounts for plant growth; carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur

Question 13

micronutrient

Answer 13

nutrient required in small amounts; also called trace element

Question 14

mineral soil

Answer 14

type of soil that is formed from the weathering of rocks and inorganic material; composed primarily of sand,
silt, and clay

Question 15

nitrogenase

Answer 15

enzyme that is responsible for the reduction of atmospheric nitrogen to ammonia

Question 16

nodules

Answer 16

specialized structures that contain Rhizobia bacteria where nitrogen fixation takes place

Question 17

O horizon

Answer 17

layer of soil with humus at the surface and decomposed vegetation at the base

Question 18

organic compound

Answer 18

chemical compound that contains carbon

Question 19

parasitic plant

Answer 19

plant that is dependent on its host for survival

Question 20

parent material

Answer 20

organic and inorganic material in which soils form

Question 21

rhizobia

Answer 21

soil bacteria that symbiotically interact with legume roots to form nodules and fix nitrogen

Question 22

rhizosphere

Answer 22

area of soil affected by root secretions and microorganisms

Question 23

sand

Answer 23

soil particles between 0.1–2 mm in diameter

Question 24

saprophyte

Answer 24

plant that does not have chlorophyll and gets its food from dead matter

Question 25

silt

Answer 25

soil particles between 0.002 and 0.1 mm in diameter

Question 26

soil

Answer 26

outer loose layer that covers the surface of Earth

Question 27

soil profile

Answer 27

vertical section of a soil

Question 28

symbiont

Answer 28

plant in a symbiotic relationship with bacteria or fungi

Question 29

organic soil

Answer 29

type of soil that is formed from sedimentation; composed primarily of organic material