29: plant nutrition

Question 1

what replaces mineral nutrients that have been lost from the soil?

Answer 1

fertilization

Question 2

commercial fertilizers are enriched in?

Answer 2

• nitrogen
• phosphorus
• potassium

Question 3

80-90% of a plant’s fresh mass is?

Answer 3

water

Question 4

4% of a plant’s dry mass is?

Answer 4

inorganic substances from soil

Question 5

96% of a plant’ dry mass is from?

Answer 5

CO2 assimilated into carbohydrates during photosynthesis

Question 6

how many essential elements are required for a plant to complete its life cycle and reproduce?

Answer 6

seventeen (17)

Question 7

macronutrients

Answer 7

9 essential elements that plants need in large amounts like C, O, H, N, P, S, K, Ca, Mg

Question 8

micronutrients

Answer 8

8 essential nutrients that plants need in small amounts like Cl, Fe, Mn, B, Zn, Cu, Ni, Mo

Question 9

cations adhere to negatively charge soil particles to?

Answer 9

prevent them from leaching out of the soil through ground water

Question 10

during cation exchange, which cation is usually displaced from soil particles by other cations?

Answer 10

hydrogen

Question 11

which elements can enter the soil solution and can be taken up by plant roots?

Answer 11

displaced cations

Question 12

deficiency of mobile nutrients usually affects?

Answer 12

older organs more than young ones

Question 13

deficiency of immobile nutrients usually affects?

Answer 13

younger organs more than older ones

Question 14

rhizosphere

Answer 14

the layer of soil closely surrounding the plant’s roots

Question 15

what thrives in the rhizosphere?

Answer 15

free-living bacteria

Question 16

_____ depend on nutrients secreted by plants, and in return helps to enhance plant growth

Answer 16

rhizobacteria

Question 17

which chemical element can be an important limiting nutrient for plant growth?

Answer 17

nitrogen

Question 18

which forms of nitrogen can plants absorb?

Answer 18

NO3 (nitrate), or NH4 (ammonium)

Question 19

what can convert atmospheric nitrogen to NO3, and NH4?

Answer 19

bacteria

Question 20

nodules

Answer 20

swelling alone legume roots composed of plant cells infected by nitrogen fixing rhizobium

Question 21

inside the root nodule, rhizobium takes a form called?

Answer 21

bacteroids

Question 22

2 types of mycorrhizal?

Answer 22

• ectomycorrhiza
• arbuscular mycorrhizae

Question 23

ectomycorrhiza

Answer 23

where mycelium forms a sheath over the root but doesn’t penetrate root cells

Question 24

arbuscular mycorrhizae

Answer 24

the hyphae extends into the root and penetrates the cell wall but not the plasma membrane

Question 25

3 non-mutualistic adaptations?

Answer 25

- epiphytes - parasitic plants - carnivorous plants

Question 26

epiphyte

Answer 26

plant that grows on other plants but obtains nutrients from rain