Plant Physiology Exam quiz and
answers graded A+
Define an essential element in regards to plant nutrition - ANS✅✅necessary for normal growth &
reproduction, cannot be functionally replaced by a different element and has one or more roles in
plant metabolism
Absence causes abnormalities & can be lethal
Also regulate gene expression & signaling
Define and list macronutrients of plants - ANS✅✅Nutrients required in large quantities by plants
N, K, P, Ca, Mg, S, Si
Micronutrients - ANS✅✅Nutrients required in small quantities by plants and are required at
different amounts during certain developmental stages
Cl, Fe, B, Mn, Na, Zn, Cu, Ni, Mo
What are the Functions of Nitrogen (N) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: synthesis of proteins (growth & yield), nucleic acids coenzymes,
chlorophylls
deficiency symptoms: stunted growth, light-green newer leaves, older leaves yellow and die
(chlorosis)
What are the Functions of Phosphorous (P) as an essential nutrient in plants? How could you
recognize a deficiency? - ANS✅✅functions: cellular division, formation of energetic structures,
nucleic acids, phospholipids, coenzymes
deficiency symptoms: purplish veins, stunted growth, fewer seeds/fruits
What are the Functions of Potassium (K) as an essential nutrient in plants? How could you recognize
a deficiency? - ANS✅✅functions; regulates sugar transport in phloem - increase tuber and root
growth -- transport of sugars, stomata control, cofactor of enzymes, reduces susceptibility to
diseases, activate enzymes, maintain water balance
deficiency symptoms: reduced growth; curled, mottled, or spotted older leaves; burned leaf edges;
weakened plant
,What are the Functions of Calcium (Ca) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: Major building block in cell walls, reduces susceptibility to
diseases, key signaling molecule, enzyme cofactor
deficiency symptoms: leaves deformed; terminal buds die; poor root growth
What are the Functions of Sulfur (S) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: synthesis of essential amino acids cystine and methionine,
coenzyme A
deficiency symptoms: light-green or yellowed leaves, reduced growth
What are the Functions of Magnesium (Mg) as an essential nutrient in plants? How could you
recognize a deficiency? - ANS✅✅functions: central part of chlorophyll molecule, activation of
enzymes
deficiency symptoms: older leaves yellow and die (chlorosis), drooping leaves
What are the Functions of Iron (Fe) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: chlorophyll synthesis, electron transport, component of
cytochrome
deficiency symptoms: older leaves yellow and die (chlorosis), yellow and green striping in grasses
What are the Functions of Manganese (Mn) as an essential nutrient in plants? How could you
recognize a deficiency? - ANS✅✅functions: necessary in the photosynthesis process, role in
chlorophyll synthesis, coenzyme action
deficiency symptoms: dark veins, but leaves whiten and fall off
What are the Functions of Boron (B) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: formation of cell wall, germination and elongation of pollen tube,
metabolism and transport of sugars, roles in flowering, fruiting, cell division, nitrogen metabolism
deficiency symptoms: terminal buds, lateral branches die; leaves thicken, curl and become brittle
What are the Functions of Zinc (Zn) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: auxins synthesis, role in formation of chloroplasts and starch,
enzyme component
deficiency symptoms: older leaves yellow and die (chlorosis), mottled or bronzed leaves, abnormal
roots
, What are the Functions of Copper (Cu) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: influences metabolism of nitrogen and carbohydrates, component
of several enzymes
deficiency symptoms: older leaves yellow and die (chlorosis), dead spots in leaves, stunted growth
What are the Functions of Molybdenum (Mo) as an essential nutrient in plants? How could you
recognize a deficiency? - ANS✅✅functions: component of nitrate-reductase and nitrogenase
enzymes
deficiency symptoms: pale green, rolled or cupped leaves
potassium demand during crop cycle - ANS✅✅highest requirement during bulking up stage of
tubers - invloved in transport of sugars
Sucrose movement - ANS✅✅- loaded into phloem companion cells by a protein symporter (SUC)
- H+/pumping ATPase establishes proton gradient -- high in phloem parenchyma and low in
companion cells
- potassium channels moves potassium from phloem parenchyma cells to companion cells to
balance electropositive gradient
nitrogen demand in crop cycle - ANS✅✅required during vegetative growth, flowering and seed
formation
phosphorus demand in crop cycle - ANS✅✅high supply of phosphorus to support photosynthesis
and cell division in accelerated vegetative growth
Mobile Essential Elements - ANS✅✅Can move from mature organs to growing organs, aiding plant
growth
Nitrogen, Potassium, Magnesium, Phosphorus, Chlorine, Sodium, Zinc, Molybdenum
Immobile Essential Elements - ANS✅✅Deficiency affects growth of organs
calcium, sulfur, iron, boron, copper
answers graded A+
Define an essential element in regards to plant nutrition - ANS✅✅necessary for normal growth &
reproduction, cannot be functionally replaced by a different element and has one or more roles in
plant metabolism
Absence causes abnormalities & can be lethal
Also regulate gene expression & signaling
Define and list macronutrients of plants - ANS✅✅Nutrients required in large quantities by plants
N, K, P, Ca, Mg, S, Si
Micronutrients - ANS✅✅Nutrients required in small quantities by plants and are required at
different amounts during certain developmental stages
Cl, Fe, B, Mn, Na, Zn, Cu, Ni, Mo
What are the Functions of Nitrogen (N) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: synthesis of proteins (growth & yield), nucleic acids coenzymes,
chlorophylls
deficiency symptoms: stunted growth, light-green newer leaves, older leaves yellow and die
(chlorosis)
What are the Functions of Phosphorous (P) as an essential nutrient in plants? How could you
recognize a deficiency? - ANS✅✅functions: cellular division, formation of energetic structures,
nucleic acids, phospholipids, coenzymes
deficiency symptoms: purplish veins, stunted growth, fewer seeds/fruits
What are the Functions of Potassium (K) as an essential nutrient in plants? How could you recognize
a deficiency? - ANS✅✅functions; regulates sugar transport in phloem - increase tuber and root
growth -- transport of sugars, stomata control, cofactor of enzymes, reduces susceptibility to
diseases, activate enzymes, maintain water balance
deficiency symptoms: reduced growth; curled, mottled, or spotted older leaves; burned leaf edges;
weakened plant
,What are the Functions of Calcium (Ca) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: Major building block in cell walls, reduces susceptibility to
diseases, key signaling molecule, enzyme cofactor
deficiency symptoms: leaves deformed; terminal buds die; poor root growth
What are the Functions of Sulfur (S) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: synthesis of essential amino acids cystine and methionine,
coenzyme A
deficiency symptoms: light-green or yellowed leaves, reduced growth
What are the Functions of Magnesium (Mg) as an essential nutrient in plants? How could you
recognize a deficiency? - ANS✅✅functions: central part of chlorophyll molecule, activation of
enzymes
deficiency symptoms: older leaves yellow and die (chlorosis), drooping leaves
What are the Functions of Iron (Fe) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: chlorophyll synthesis, electron transport, component of
cytochrome
deficiency symptoms: older leaves yellow and die (chlorosis), yellow and green striping in grasses
What are the Functions of Manganese (Mn) as an essential nutrient in plants? How could you
recognize a deficiency? - ANS✅✅functions: necessary in the photosynthesis process, role in
chlorophyll synthesis, coenzyme action
deficiency symptoms: dark veins, but leaves whiten and fall off
What are the Functions of Boron (B) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: formation of cell wall, germination and elongation of pollen tube,
metabolism and transport of sugars, roles in flowering, fruiting, cell division, nitrogen metabolism
deficiency symptoms: terminal buds, lateral branches die; leaves thicken, curl and become brittle
What are the Functions of Zinc (Zn) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: auxins synthesis, role in formation of chloroplasts and starch,
enzyme component
deficiency symptoms: older leaves yellow and die (chlorosis), mottled or bronzed leaves, abnormal
roots
, What are the Functions of Copper (Cu) as an essential nutrient in plants? How could you recognize a
deficiency? - ANS✅✅functions: influences metabolism of nitrogen and carbohydrates, component
of several enzymes
deficiency symptoms: older leaves yellow and die (chlorosis), dead spots in leaves, stunted growth
What are the Functions of Molybdenum (Mo) as an essential nutrient in plants? How could you
recognize a deficiency? - ANS✅✅functions: component of nitrate-reductase and nitrogenase
enzymes
deficiency symptoms: pale green, rolled or cupped leaves
potassium demand during crop cycle - ANS✅✅highest requirement during bulking up stage of
tubers - invloved in transport of sugars
Sucrose movement - ANS✅✅- loaded into phloem companion cells by a protein symporter (SUC)
- H+/pumping ATPase establishes proton gradient -- high in phloem parenchyma and low in
companion cells
- potassium channels moves potassium from phloem parenchyma cells to companion cells to
balance electropositive gradient
nitrogen demand in crop cycle - ANS✅✅required during vegetative growth, flowering and seed
formation
phosphorus demand in crop cycle - ANS✅✅high supply of phosphorus to support photosynthesis
and cell division in accelerated vegetative growth
Mobile Essential Elements - ANS✅✅Can move from mature organs to growing organs, aiding plant
growth
Nitrogen, Potassium, Magnesium, Phosphorus, Chlorine, Sodium, Zinc, Molybdenum
Immobile Essential Elements - ANS✅✅Deficiency affects growth of organs
calcium, sulfur, iron, boron, copper
