Ch. 39 Plant Nutrition

Question 1

essential nutrient

Answer 1

any chemical element, ion, or compound that is required for normal growth, reproduction, and maintenance of a living organism
- cannot be synthesized by the organism

Question 2

examples of essential nutrients

Answer 2

1) carbon
2) hydrogen
3) oxygen

Question 3

ways to obtain essential nutrients

Answer 3

1) from water
2) from the air
3) from the soil

Question 4

macronutrient

Answer 4

any element that is required in large quantities for normal growth, reproduction, and maintenance of a living organism
- major components of nucleic acids, proteins & phospholipids

Question 5

examples of macronutrients

Answer 5

1) nitrogen
2) phosphorus
3) potassium

Question 6

limiting nutrient

Answer 6

any essential nutrient whose scarcity in the environment reduces growth & reproduction of organisms

Question 7

examples of limiting nutrients

Answer 7

nitrogen

phosphorus

potassium

Question 8

micronutrient

Answer 8

any element that is required in very small quantities for normal growth, reproduction, and maintenance of a living organism
- function as cofactors of specific enzymes

Question 9

examples of micronutrients

Answer 9

iron

boron

copper

nickel

Question 10

nitrogen deficient plant

Answer 10

yellowing of leaves

Question 11

phosphorous deficient plant

Answer 11

stunted growth

dead spots

brown

Question 12

mobile elements

Answer 12

nitrogen / potassium / phosphorous

when limited, they are transferred from older leaves to newer leaves

scarcity reflected in determination of older leaves

Question 13

immobile elements

Answer 13

calcium / iron / copper

remain tied to older leaves

scarcity is reflected in newer leaves

Question 14

hydroponic growth

Answer 14

growth of plants in liquid cultures instead of soil

Question 15

weathering

Answer 15

gradual wearing down of large rocks by rain, running water, temperature changes, and wind
- one of the processes that transform rocks into soil

Question 16

flakes & pebbles (weathering)

Answer 16

break off from the solid rock

- the first ingredients in soil

Question 17

humus

Answer 17

decayed organic matter in soils

Question 18

texture

Answer 18

quality of soil, resulting from relative abundance of different-sized particles

proportions of gravel, sand, silt, and clay

Question 19

soil texture affects:

Answer 19

1) penetration of soil
2) soil’s ability to hold water
3) availability of oxygen

Question 20

mature soil

Answer 20

a complex mixture of organic and inorganic components

Question 21

loam

Answer 21

soil that contain equal amounts of soil, silt & clay w/ a high proportion of humus

• best soil
• contain organic matter
• good texture

Question 22

sustainable agriculture

Answer 22

agricultural techniques that are designed to maintain long-term soil quality and productivity

Question 23

leaching

Answer 23

loss of nutrients from soil via percolating water (washing)

Question 24

anion

Answer 24

ions with negative charges

• usually dissolve in soil water
• interact with water molecules via hydrogen bonding

Question 25

cation

Answer 25

ions with positive charges - dissolve in soil water - not as immediately available as anions

Question 26

examples of sustainable agriculture

Answer 26

1) planting rows of trees as windbreaks 2) minimizing the amount of plowing & tilling needed to control weeds 3) planting crops in strips that follow the contour of hillsides

Question 27

ion

Answer 27

charged particle

Question 28

role of soil pH

Answer 28

low pH = acidic (high concentrations of hydrogen ions) high pH = basic / alkaline (few hydrogen ions)

Question 29

cation exchange

Answer 29

displacement of protons or cations by protons in soil water | - released cations available for plant uptake

Question 30

zone of maturation

Answer 30

(in plant roots) a group of plant cells located several millimeters behind the root cap - they are differentiating into mature tissues - nutrient uptake occurs here

Question 31

root hair

Answer 31

extensions of the epidermal cells in the zone of maturation

Question 32

membrane potential

Answer 32

a difference in electric charge across a cell membrane - a form of potential energy aka membrane voltage

Question 33

symbiotic

Answer 33

"living together" any close and prolong physical relationship between individuals of 2 different species

Question 34

mutualistic

Answer 34

organism that is a participant and partner in a mutualistic relationship - mutually beneficial

Question 35

metallothionein

Answer 35

small plant protein that bind to & prevent excess metal ions from acting as toxins - active exclusion - requires energy

Question 36

tonoplast

Answer 36

membrane surrounding the large, central vacuole

Question 37

ectomycorrhizal fungi (EMF)

Answer 37

fungi that have hyphae that wrap around the epidermal cells of roots

Question 38

arbuscular mycorrhizal fungi (AMF)

Answer 38

fungi that have hyphae that can penetrate the walls of plant root cells

Question 39

nitrogen fixation

Answer 39

the incorporation of atmospheric nitrogen (N2) into ammonia (NH2), which can be used to make many organic compounds - occurs in only a few lineages of bacteria & archaea

Question 40

nodule

Answer 40

globular structure on roots of legume plants that contain symbiotic nitrogen-fixing bacteria look like little moles on the roots

Question 41

leghemoglobin

Answer 41

iron-containing molecule similar to hemoglobin - found in infected cells of legume root nodules - oxygen binding - creates pink coloration

Question 42

nod factor

Answer 42

molecule produced by nitrogen-fixing bacteria that help them recognize & bind to roots of legumes

Question 43

epiphytic plant

Answer 43

"upon plants" a nonparasitic plant that grows on the trunks or branches of other plants - not rooted in soil

Question 44

where do epiphytes get their nutrients?

Answer 44

from rainwater, dust & particles that collect in their tissues and crevices of bark

Question 45

parasite

Answer 45

an organism that lives on a host species (ectoparasite) or in a host species (endoparasite) - damages the host

Question 46

carnivorous plant

Answer 46

plants that use modified leaves to trap insects & other animals - make their own carbohydrates via photosynthesis - use carnivory to supplement the nitrogen available in the environment