Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chapter 14: Soils and Mineral Nutrition - Coggle Diagram
Chapter 14: Soils and Mineral Nutrition
Essential Elements
hydroponic solution
single element is supplied to a plant in excessive quantities to make it grow
macro essential elements
carbon
organic compounds
oxygen
hydrogen
nitrogen
amino acids
nucleic acids
chlorophyll
potassium
amino acids
osmotic balance
enzyme activator
guard/motor cell movement
calcium
controls enzyme activity
middle lamela component
affects membrane properties
phosphorus
ATP
nucleic acids
phospholipids
coenzymes
magnesium
chlorophyll
activates many enzymes
sulfur
coenzyme A
some amino acids
micro essential elements
iron
cytochromes
nitrogenase
chlorophyll synthesis
chlorine
water-splitting reactions in photosynthesis
copper
plastocyanin
manganese
chlorophyll synthesis
enzyme activity
zinc
activates enzymes
Molybdenum
Nitrogen reduction
boron
Mineral Deficiency Diseases
Causes of Deficiency Diseases
soils may have low concentrations of essential elements
example is serpentine soil
extremely deficient in potassium and phosphorus
Symptoms of Deficiency Diseases
chlorosis
leaves lack chlorophyll
yellowish color
brittle leaves
necrosis
death of patches of tissue
Mobile Elements
chlorine
magnesium
nitrogen
phosphorus
potassium
sulfur
Immobile elements
boron
calcium
iron
Soils and Mineral Availability
weathering
physical weathering
breakdown of rock by physical forces
wind
water movement
temperature changes
ice
produces variety of sizes of soil particles
coarse sand (2.0-0.2 mm) (largest)
fine sand (0.2-0.02 mm) (1/10 smaller than coarse sand)
slit (0.02-0.002 mm) (1/10 size of fine sand)
clay particles (<0.002 mm in diameter)
known as micelles
chemical weathering
chemical reactions
acids produced by decaying bodies
plants
fungi
Cation exchange
cations freely dissolve in soil solution
roots give off CO2
reacts with water forming carbonic acid
acid dissociates into proton & anion
may be diffused or absorbed/transported
Soil Acidity
as pH gets lower, concentration of protons causes more cations to be released from soil micelles
absorbed by roots
washed away in ground water
high alkaline soils (pH 9.0-10.0)
infrequent in dry climates
have too few protons to allow cation release
concentrations of minerals excessively high
Mycorrhizae and the Absorption of Phosphorus
mycorrhiza
roots of 90% of all species of plants form a symbiotic association with soil fungi
permits plants to absorb phosphorus efficiently
vascular/arbuscular mycorrhiza
fungal filaments penetrate root cortex cells
form tree-shaped arbuscule inside the cell
fungus collects phosphorus from soil and transports it into arbuscules
phosphorus accumulates as granules
phosphorus transported into the root cell protoplasm
Nitrogen Metabolism
nitrogen
does not occur as a component of rock matrixes or contaminant of rock
most abundant source in atmospheric gas N2
chemically inert
useless to almost all organisms
must be converted to chemically active forms
nitrogen metabolism
(1) nitrogen fixation
(2) nitrogen reduction
(3) nitrogen assimilation
Nitrogen Fixation
conversion of N2 gas into
nitrate
all forms of nitrogen that are substrates for a variety of enzymes
nitrite
ammonium
human manufacturing
fertilizer industry synthesizes nitrate or ammonium from atmospheric nitrogen
extremely expensive to do
energy intensive process
about 110 million tons of nitrogen fertilizer are produced annually
natural processes
fix over 190 million tons of nitrogen annually
lightning
converts elemental nitrogen to useful form
dissolves in rain and falls to earth
nitrogen-fixing bacteria/cyanobacteria
convert 130 million tons of nitrogen to forms that plants/animals can use
nitrogenase
extremely slow enzyme that uses N2 as substrate
forces electrons and protons onto nitrogen
nitrogen reduced from +0 to -3 oxidation state
ammonia (NH3) is the product
dissolves in cell's water and picks up proton
1 more item...
giant enzyme complex
composed of two distinct enzymes
dinitrogenase
composed of 4 proteins
dinitrogenase reductase
composed of 2 proteins
Nitrogen Reduction
process of reducing nitrogen from an oxidation state of +5 to -3 (ammonium)
requires 8 electrons from each nitrogen
nitrate reductase
carries electrons by means of a molybdenum atom
FADH2
NADH
carry electrons to oxidized nitrate reductase
Nitrogen Assimilation
incorporation of ammonium into organic molecules in the plant body
similar mechanism to ETC
acceptor molecule is glutamate
reacts with ammonium and ATP
produces glutamine and ADP
glutamine transfers ammonium (now referred to as an amino group) to a-ketoglutarate
transforms molecules into glutamate (starter molecule). An extra glutamate molecule is produced to transfer its amino group.
if oxaloacetate receives amino group
aspartate produced
if pyruvate receives amino group
alanine produced
transamination
the transfer of an amino group from one molecule to another
Other Aspects of Prokaryotes and Nitrogen
nitrifying bacteria
some oxidize ammonium to nitrite
some oxidize nitrite to nitrate
entire process is called nitrification
denitrification
certain bacteria reduce nitrate to gaseous nitrogen, N2
Obtaining Nitrogen from Animals
carnivorous plants
obtain significant fraction of reduced nitrogen by catching animals
ant-plants
have hollow chambers which ants use as living spaces/graveyards
ants decompose and give off nitrogen
mutualistic relationship with ants
domatium
chamber formed by plant used commonly as a living space by animal
