soil microbio

Question 1

bacteroid

Answer 1

N2 icing bacteria after activated by root nodule

Question 2

Rhizobium

Answer 2

soil bacteria that infect roots of legumes to form root nodules where they fix nitrogen gas and turn it into useful nitrogen for the plants= symbiotic relationship

Question 3

nodules are surrounded by

Answer 3

plant cytoplasm

Question 4

leghemoglobin

Answer 4

controls o2 levels (binding o2 protein) produced by plant cells

Question 5

Mucilage

Answer 5

viscous sugar rich fludid secreted by some plants that contain N-fixing bacteria

Question 6

plants can use both ____ and ____

Answer 6

ammonium (NH4+) and nitrate (NO3-)

Question 7

sources of nitrate

Answer 7

ammonia to nitrite to nitrate

Question 8

if soil becomes waterlogged, it becomes anaerobic which promotes _________

Answer 8

denitrification:
NO3- to nitrite ti NO to N2O to N2 gas

also promote suffer reductions to H2 gas

Question 9

humus

Answer 9

dead plant material that is resistant to decomposition - good for soil fertility

Question 10

prokaryotes are responsible for

Answer 10

production of humus
release minerals into soil
cycle nutritients
N fixing

Question 11

Cyanobacteria

Answer 11

free living

Question 12

Rhizobium

Answer 12

symbiotic- provides AA to the plant and fix nitrogen

Question 13

Nitrogen fixing is catalyzed by ________

Answer 13

denitrogenase reductase

Question 14

nitrogen fixation requires _____ from ______

Answer 14

8 electrons from pyruvate

Question 15

Dinitrogenase reductase is inhibited by______

Answer 15

oxygen

Question 16

Azotobacter

Answer 16

free living, strict aerobe

Question 17

free-living nitrogen fixers

Answer 17

Clostridium, Azotobacter and Cyanobacteris

Question 18

plants provide organic acids and ________

Answer 18

leghemoglobin for the bacteriod