MINERAL NUTRITION Flashcards
define hydroponics
soil-less growth of plants in a solution mineral solution
hydroponics introduced by
Julius Von Sachs
in the hydroponics experimental set up why is the lid covered by black paper
prevent algal contamination prevent roots from reacting to sunlight
significance of hydroponics
can be used in areas with thin infertile soil pH can be altered for specific plants soil borne pathogens are controlled problem of weeding is avoided
when is a mineral defined an essential
if the mineral has a specific structural of physiological role without which the plant cannot survive
criteria for an element to be classified as essential was introduced by
Arnon and stout
criteria for an element to be essential
How many macronutrients are present in plants
9
name the macronutrients
C , H , O , N , P , K , S , Mg , Ca
how much macro and micro nutrients are present in 1 kg of dry weight of the plant
10 mmoles / kg
< 10 mmoles / kg
excess of macronutrients is toxic for the plants
TRUE OR FALSE
FALSE
Not toxic
excess fo micronutrients is toxic for plants
TRUE OR FLASE
TRUE
Name the beneficial elements
Na, Co , Si, selinium
function of macro nutrients
formation of major biomolecules
for building of plant body and protoplasmic constituents
function of micronutrients
required for functioning of enzymes
name the structural elements
C, H, O, N
Nitrogen is a constituent in (3)
chlorophyll
amino acids
proteins
elements present in energy-related compounds
Mg in chlorophyll
P in ATP
Elements that are activators and inhibitors
Mg2+
Mo
Zn2+
Mn2+
Mg2+ is activator for
ribulose bisphosphate carboxylase oxygenase (RuBisCO)
Phosphenlose pyruvate carboxylase (PEPcase)
alcohol dehydrogenase is activated by
Zn2+
nitrogenase is activated by
Mo
photolysis of water aided by
Mn2+
osmotic potential and cell turgidity is maintained by
K , Cl , sulphate
opening and closing of stomata maintained by
K
Phophate acts as a
buffer
which element is needed in greatest amounts
Nitrogen
nitrogen is absorbed mainly in …………
and also in the form ……..&……..
NO3 -
NO2 - , NH4 +
meristematic tissue and metabolically active cells require which element
nitrogen
phosphorous is absorbed as
phosphate ions
phosphorous is present in
developing fruit , seeds , storage organs , young meristematic tissue
role of phosphorous
RNA , DNA , ATP , NADP
Deficiency of phosphrous leads to
purple red spots on leaves
delay in seed germination
potasium absorbed as
K+
role of potassium
anion cation balance
protein synthesis
opening of stomata
activates enzymes present in reactions such as phosphorylation , photosynthesis , respiration and synthesis of chlorophyll
maintains cell tugidity
deficiency of potassium leads to
scorched leaf tips
decreased cambial activity
degeneration of plastids
calcium is required at
meristematic tissue and differentiating tissue
calcium is absorbed in the form of
Ca2+
role of calcium
forms middle lamella
required in formation of spindle fibers
required for normal working of cell membrane
activates enzymes like ATPase, alpha-amylase , phospholipase
magnesium absorbed in the form of
Mg2+
magnesium is required where
at the growing parts of stem , roots, seeds , leaves
role of magnesium
formation of middle lamella
required for association of ribosome subunits
activates enzymes involved in photosynthesis and respiration
part of the chlorophyll structure
involved in DNA and RNA synthesis
sulphure is abosorbed in which form
sulphate ion
role of sulphure
constituent of methionine and cysteine
required for formation of biotin and thiamine , coenzyme A , ferredoxin
deficiency of sulphur leads to
accumulation of anthocyanin
which micronutrient is needed in highest quantities
iron
iron is absorbed in which form
Fe3+ (ferric)
where is sulphur required
young leaves and meristem
where is iron required
in all parts of the plant
role of iron
constituent of proteins involved in electron transfer like ferredoxin , cytochrome
activates enzyme catalase
required for chlorophyll formation
which form is manganese absorbed in
manganous ion Mg2+
role of manganese
aids in photolysis of water
deficiency of manganese causes
gray spots in oats
zinc absorbed as
Zn2+
function of zinc
activates enzyme carboxylase
aids in synthesis of auxin
participates in tryptophan synthesis
defiency of zinc causes
leaf malformation
or
little leaf
copper absorbed as
Cu2+
role of copper
associated with proteins involved in electron transfer
Boron absorbed as
BO 3- , B4O7 2-
role of boron
Required for uptake and utilization of Ca2+
needed for carbohydrate translocation
needed for pollen germination
needed cell elongation and differentiation
deficiency of boron leads to
loss of apical dominance
absence of root nodules in legumes
molybdenom absrobed as
molybdate ions (MoO2 -2 )
funtion of molybdenum
involved in nitrogen fixation
component of enzymes such as nitrogenase and nitrate reductase
chlorine absorbed as
chloride ion (Cl-)
function of chlorine
anion cation balance along with Na and K
Also involved in Photolysis of water along with manganese
Nickle absorbed as
Ni2+
funtion of nickle
component of urea and hydrogenase
involved in urea metabolism
nitrogen found where
all parts especially meristematic regions
calcium found where
meristem and differentiating tissue
phophrous found
developing fruit , seed , storage organs
iron found
everywhere
nickle found
seeds and leaves
chlorine found
everywhere
molybdenum found
everywhere , especially in roots
boron found where
leaves and seeds
zinc found where
everywhere
copper found where
everywhere
manganese found
leaves and seeds
deficiency symptom AKA
hunger sign
define critical concentration
the concentration of an essential element below which the growth of a plant is retarded
Deficiency of what will cause chlorosis
(nani kovid mugged story from my zinc mohamed)
N , K , Mg , S , Fe , Mn , Zn , Mo
deficincy of what will cause necrosis
Ca , Mg , Cu , K
deficiency of what would cause inhibition of cell division
N , K , S , Mo
deficiency of what will cause late flowering
N, S , Mo
toxicity of Mn would cause
Prevention of uptake of Mg , Fe
prevent Mg from binding with enzymes
prevents Ca translocation
brown spots surrounded by chlorotic viens
mineral absorption divided into 2 phases
initial phase
metabolic phase
explain initial phase
passive entry of ions vio ion channels into apoplast
explain metabolic phase
entry of ions into symplast by active transport
entry of ion is influx
exit of ions is efflux
which is the limiting nutrient in natural and agricultural ecosystem
nitrogen
what form does nitrogen exist in in the atmosphere
N2
how much % of atmosphere is nitrogen
78%
conversion of N2 to ammonia is called
nitrogen-fixing
types of nitrogen fixing
Atmospheric NF
industrial NF
biological NF
Explain atmosphereic nitrogen fixing
UV and lightening provide enough energy for N2 to react with oxygen to form NO , NO2 , N20
explain industrial nitrogen fixing
Automobile exhaust and power station are good source of oxides of nitrogen
Explain biological nitrogen-fixing
cyanobacteriaand other bacteria can fix atmospheric nitrogen to form NH3 with the help of nitrogenase enzyme
name free living N2 fixing bacteria and state whether aerobic or anaerobic
Azotobacter (aerobic)
Beijerinkio (aerobic)
rhodospirlium (anaerobic)
clostridium (anaerobic)
name free living nitrogen fixing cyanobacteria
anabeana , nostoc
name symbiotic nitrogen fixing bacteria
rhizobium, Frankia
what are the steps of nitrogen cycle
nitrogen fixing
ammonification
nitrification
denitrofication
explain ammonification
conversion of decomposing organic nitrogen to ammonia
bacteria aiding ammonifcation
bacillus Vulgaris , bacillus ramosus , actinomycetes
explain nitrification
some ammonia volatize to atmosphere but some converted to nitrate by soil bacteria
2 steps
ammonia -> NO2 -
NO2- -> NO3 -
What is the step 1 of nitrification and name the bacteria aiding in the process
ammonia to nitrite
nitrosomonas
nitrococcus
what is step 2 of nitrification and name the bacteria
nitrite to nitrate
nitrobacter
nitrocystis
name the chemoautotrophs associated with nitrification
nitrosomonas & nitrobacter
why is nitrate converted to ammonia in the plant
nitrate cannot be used by the plant
what is nitrate assimilation
conversion of nitrate to nitrite to ammonia
in nitrate assimilation, nitrate to nitrite is carried out by which enzyme
nitrate reductase
nitrate reductase activated by which element
molybdenum
out of nitrate reductase and nitrite reductase which one is a flavoprotein
nitrate reductase
nitrite to ammonia is done by which enzyme
nitrite reductase
what is the source of electrons source for reduction of nitrite to ammonia
ferredoxin
nitrite reductase is associated with which elements
copper and iron
explain denitrification
left over nitrates in soil is converted to gaseous nitrogen
denitrification carried out by which bacteria
pseudomonas denitrificants
thiobascillus denitrificants
which bacteria forms nodules in leguminous plants
rhizobium
which bacteria forms nodules in non-leguminous plants
Frankia
explain nodule formation by rhizobium
rhizobium multiply and colonize a root hair
rhizobium produced Nod factor causing curling of root and hair and they enter the root hair forming an infection thread
bacteria reach the cortex and initiate nodule formation
bacteria stop dividing and form rod shape structure called bacteriod
bacteria release signals to cause the inner corticle and pericycle to divide to form the nudule
how are nodules good for nitrogen fixing
contain enzyme nitrogenase and red pigment called leghemoglobin
during nitrogen fixing
N2 is reduced by H+ provided
NADPH2 , FMNH2
by addition of H+ during nitrogen fixing , N2 is converted to
dimide, N2H2
Dimide is reduced to
hydrazine , N2H4
hydrazine is reduced to
ammonia
how many ATP molecules required to form 1 NH3 molecules
8
function of leghemoglobin
nitrogenase enzyme requires anaerobic conditions
leghemoglobin is an O2 scavenger and therefor protects nitrogenase from oxygen
why is NH4+ assimilated as soon as it is formed
becuse it is toxic
methods by which ammonium is assimilated
1) reductive amination
2) transamination
