Plant Physiology most important questions for competitive exams

Plant Physiology most important questions for competitive exams

  1. Brassino steroid is present in

(a) Mustard

(b) Cotton

(c) Wheat

(d) Sunflower

  1. In C, plant, which enzyme first react with CO₂ to form PGA

(a) Invertases

(b) Rubisco

(c) Oxaloacetate

(d) PEP

  1. Nitrate reductase is found in

(a) Chloroplast

(b) Cytokinin

(c) Mitochondria

(d) Cytoplasm

  1. Protein content in pulses ranges from

(a) 10 15%

(b) 20 25%

(c) 25 – 30%

(d) 40 – 45%

  1. Protein content of cereals ranges from

(a) 8 12%

(b) 12 – 15%

(c) 15 – 20%

(d) 20 – 25%

  1. Natural inhibitor of IAA oxidases is

(a) Caffeic acid

(b) Coumaric acid

(c) ABA

(d) Lactic acid

  1. In C, plant, the first stable product of photosynthesis is

(a) PGA

(b) Malic acid

(c) Oxalic acid

(d) Tartaric acid

  1. Close association of chloroplast, peroxosomes and mitochondria in a leaf cell are related with

(a) Photosynthesis

(b) Respiration

(c) Photorespiration

(d) None of these

  1. How many ATP are required to produce 1 mole of hexose in photosynthesis?

(a) 8

(b) 18

(c) 28

(d) 38

  1. Instrument used for measuring ‘stomatal pressure’ is

(a) Porometer

(b) Calipers

(c) Potometer

(d) Micronare

  1. Who coined the term ‘biological clock’?

(a) Went

(b) Borthwick

(c) Salisburry

(d) Bunning

  1. Most dangerous gas for depletion of ozone layer is

(a) Chlorine

(b) CFC

(c) Benzene

(d) CO₂

  1. Which process is also known as glycolate pathway ?

(a) Photosynthesis

(b) Respiration

(c) B-oxidation

(d) Photorespiration

  1. The present level of CO, in atmosphere

(a) 210-250 ppm

(c) 360-370 ppm

(b) 295-300 ppm

(d) 420-460 ppm

  1. In C, plant, enzyme responsible for the synthesis of malic acid is

(a) PEP carboxylase

(b) Rubisco

(c) Isomerase

(d) Kinase

  1. Element for most of dehydrogenase is

(a) Ca

(b) Mo

(c) Mg

(d) Zn

  1. Lysimeter is used in

(a) Light measurement of

(b) Transpiration

(c) Lysine content

(d) Water potential

  1. Agave americana is a

(a) C, plant

(b) C4 plant

(c) CAM plant

(d) Not classified

  1. The most striking feature of CAM plants is formation of malic acid at

(a) Morning

(c) Evening

(b) Afternoon

(d) Night

  1. Select the families to which CAM plants belong.

(a) Bromeliaceae

(c) Orchidaceae

(b) Cactaceae

(d) All of these

  1. Photosynthetic inhibition by O, is called as

(a) Hill reaction

(b) Warburg’s effect

(c) Feed back inhibition

(d) Competitive effect

  1. Among the following statements which one is not correct about photosynthesis

(a) Light captured by PS – I and electron passed to PS-II

(b) O2 is released from photolysis of water

(c) ATP from electron transport chain with PS-I, PS-II

(d) Light independent reactions uses energy rich molecules to reduce CO2

  1. Among following which is antioxidant ?

(a) Quinones

(b) Tocopherols

(c) Phenols

(d) Sorbitols

  1. Which ecosystem has highest net primary productivity per unit area?

(a) Tropical seasonal forest

(b) Tropical rain forest

(c) Cultivated lands

(d) Savanna

  1. At the outer boundry of the atmosphere and at the earth’s mean distance from the sun, the total irradiance (solar constant) is

(a) 1060 Jm-28-1

(b) 1360 Jm-2s-1

(c) 1060 cal m-29-1

(d) 1360 cal m-25-1

  1. The irradiance at which photosynthesis is equal to respiration rate (net CO₂ exchange is zero) is called

(a) compensation point

(b) Light saturation point

(c) Solar constant

(d) PAR

  1. The CO2 concentration at which photosynthetic fixation just balances respiratory loss is known as the

(a) O₂ compensation point

(b) O2 saturation point

(c) CO₂ compensation point

(d) CO, saturation point

  1. The transpiration ratio is highest for

(a) C, plants

(c) CAM plants

(b) C. plants

(d) None of these

  1. Photosynthesis inhibited by 21%

(a) C, plants

(b) C. plants

(c) CAM plant

(d) None of these

  1. For C, plants, the optimum temperature for photosynthesis is

(a) 15 – 25 °C

(b) 25-30 °C

(d) 35 °C

(c) 30 – 47 °C

  1. Respiratory quotient (RQ) for carbohydrates is approximately

(a) 0.5

(b) 1.0

(c) 1.33

(d) 0.7

  1. Respiratory quotient (RQ) for fatty acids is

(a) 0.7

(b) 0.5

(c) 1.33

(d) 2.0

  1. Respiratory quotient (RQ) for organic acid is

(a) 0.7

(b) 1.0

(c) 1.33

(d) >1.0

  1. The end product of glycolysis is

(a) Glucose

(b) Sucrose

(c) Pyruvic acid

(d) NADH

  1. Glycolysis take place in

(a) Mitochondria

(b) Cytoplasm

(c) Chloroplast

(d) Nucleus

  1. Electron-transport system take place in which part of mitochondria ?

(a) Matrix

(b) Cristae

(c) Outer membrane

(d) Inner membrane

  1. Krebs cycle produces

(a) 18 ATP

(b) 30 ATP

(c) 32 ATP

(d) 36 ATP

  1. First time IAA from human urine was isolated by

(a) Kogl

(b) Went

(c) Adns

(d) Miller

  1. The term ‘skototropism’ is associated with:

(a) Jumper and Jones

(b) Mayber and Mayer

(c) Strong and Ray

(d) Hans and Knot

  1. Pollen germination requires which of the following element ?

(a) B

(b) K

(c) Ca

(d) Si

  1. Who first isolated ‘zeatin’ from corn seed ?

(a) Wiesner

(b) Miller

(c) Zeigler

(d) Letham

  1. Storage protein in beans is

(a) Insulin

(b) Globulins

(c) Phaseoline

(d) Tripsin

  1. Main organic acid in pineapple is

(a) Citric acid

(b) Pyruvic acid

(c) Malic acid

(d) Acetic acid

  1. Sulphate reduction in leaves take place in

(a) Mitochondria

(b) Chloroplast

(c) Glyoxisomes

(d) Peroxisomes

  1. Polymer of cellulose is

(a) B-D glucose

(b) a-D glucose

(c) Fructose

(d) Glucose

  1. In which cell organelle, PEP carboxylation is taking place in C, plants

(a) Epidermal cells

(b) Mesophyll cells

(c) Xylem cells

(d) Bundle sheath cells

  1. Cyanide-resistant respiration follow

(a) Pentose phosphate pathway

(b) Krebs cycle

(c) Glycolysis

(d) None of these

  1. Green house gas for global warming is

(a) O2

(c) SO₂

(d) CO₂

(b) CHA

  1. photorespiration acid produced in

(a) Serine

(c) Tryptophan

(b) Arginine

(d) Methionine

  1. In monocots and dicots accumulation of
    which hormone causes collapse and lysis of mature cortical cells in the root, leading to a tissue with large air

(a) Auxin spaces

(b) Gibberellin

(c) Ethylene

(d) ABA

  1. Aerenchyma is related with

(a) ABA

(b) Ethylene

(c) Cytokinin

(d) Auxin

  1. When starch reacts with iodine produces colour

(a) Yellow

(b) Blue

(d) Red

(c) Green

  1. Under an aerobic conditions microbes grow slower but uses more sugar and produces more CO₂ and ethanol, this phenomenon known as

(a) Warburg’s effect

(b) Pasteur effect

(c) Both (a) and (b)

(d) None of these

  1. Enzyme used to cut double stranded RNA is

(a) DNAase

(b) Reverse transcriptase

(c) Restriction endonuclease

(d) Lipase

  1. Which membrane by diffusion? across

(a) CO₂

(b) O2

(c) H₂O

(d) H+

  1. In many species, the gradual decrease in respiration is reversed by a sharp increase, known as

(a) Non climacteric

(b) Climacteric

(c) Both

(d) None

  1. Conversion of organic nitrogen to NH4
    by soil microbes is called

(a) Amminization

(b) Ammonification

(c) Nitrification

(d) Mineralization

  1. Denitrification occurs in

(a) Water logged soils

(b) Well aerated soils

(c) Alkali soils

(d) Acidic soils

  1. C, cycle of carbon fixation takes place in

(a) Nucleus

(b) Thylakoid of chloroplast

(c) Stroma of chloroplast

(d) Cytosol

  1. The process by which N, is reduced to ammonium (NH,*) is called

(a) Nitrification

(b) Nitrogen fixation

(c) Denitrification

(d) Ammonia volatilization

  1. How many electrons are required for conversion of NO₂ to NH4+

(a) 4

(b) 6

(d) 10

(c) 8

  1. Mature root nodule made largely of

(a) Diploid cells

(b) Tetraploid cells

(c) Hexaploid cells

(d) None

  1. The main function of leghaemoglobin is

(a) Fe supply

(b) Water supply

(c) O₂ supply

(d) All of these

  1. Nitrogen fixation is carried out by enzyme

(a) Nitrate reductase

(b) Nitrite reductase

(c) Nitrogenase

(d) Rubisco

  1. Nitrogenase consists of

(a) Fe protein

(b) Mo protein

(c) Fe-Mo protein

(d) None

  1. Which one of the following is a phosphorus mobilizer ?

(a) VAM

(b) Rhizobium

(d) Clostridium

(c) BGA

  1. ‘Dormin’ is coined by

(a) Skoog

(b) Wareing

(c) Addicot

(d) Wilkins

  1. anatomy is found in Kranz type of

(a) Sunflower

(b) Soybean

(c) Sorghum

(d) Spinach

  1. How many Calvin cycles are needed to produce one molecule of glucose ?

(a) 1

(b) 3

(c) 6

(d) 9

  1. The ureides (allantoin and allantoic acids) is the major nitrogen compound transported from root nodules to other parts of plant in

(a) Soybean

(b) Wheat

(c) Sugarcane

(d) Sugarbeet

  1. How many quanta are there in 1 μ Einstein?

(a) 5.074 × 10 23

(b) 6.02 x 1017

(c) 6.02 x 10-23

(d) 6.02 × 10 23

  1. Unit of pressure in SI system

(a) Atmosphere

(b) Dynes/cm²

(c) Pascal

(d) mm of mercury

  1. One millimole of CaCO, weight is

(a) 100 g

(c) 1.0 mg

(b) 1 g

(d) 0.1 g

  1. In process of nitrate reduction, the oxidation number of nitrogen changes from

(a) +3 to 5

(b) +5 to – 3

(c) +6 to -3

(d) – 2 to +5

  1. Reduction of nitrite to ammonium ions is catalyzed by nitrite reductase in

(a) Chloroplast

(b) Proplastids of roots

(c) Both a & b

(d) Cytoplasm

  1. Flowering stimulus is perceived by

(a) Shoot apex

(b) Leaves

(c) Buds

(d) Flowers

  1. D. 1-amino-cyclopropane-1-carboxylic acid (ACC) is a close precursor of

(a) ABA

(b) Ethylene

(c) Salicylic acid

(d) GA

  1. The first step of assimilation of sulphate is catalyzed by

(a) ATP sulfurylase

(b) APS sulfotransferase

(c) Pyrophosphatase

(d) Cysteine synthetase

  1. Coconut fat is a rich source of

(a) Palmitic acid

(b) Stearic acid

(c) Lauric acid (d) Ricinoleic acid

  1. Phytoalexins includes

(a) Pisatin

(b) Phaseolin

(c) Isocoumarin

(d) All of these

  1. Flavonoides includes

(a) Anthocyanins

(b) Flavonols

(c) Flavones

(d) All of these

  1. Betalains have role in

(b) Pollination

(a) Germination

(c) Fruit setting

(d) Ripening

  1. The first alkaloid to be isolated and crystallized was the

(a) Nicotine

(b) Cocaine

(c) Morphine

(d) Caffeine

  1. Nicotine is produced only in

(a) Roots

(c) Seed

(b) Leaves

(d) Stem

  1. A cell lacking cell wall is also lack in

(a) Biomembrane

(b) Chloroplast

(c) Endoplasmic reticulum

(d) Mitochondria

  1. cDNA stands for

(a) Copy DNA

(b) Cyclic DNA

(c) Complementary DNA

(d) Both (a) and (b)

  1. Dry weight is commonly obtained by drying the freshly harvested plant material at

(a) 60-70 °C

(b) 70-80 °C

(c) 90-100 °C

(d) 100-105 °C

  1. In bamboos (Bambusa), which live more than half century, flowering occurs only

(a) Once

(b) Twice

(d) Not countable

(c) Thrice

  1. Fluorescence which is sensitive to the conditions of photothermal traps are said to be

(a) Constant fluorescence

(b) Dead fluorescence

(c) Background fluorescence

(d) Variable fluorescence

  1. The century plant (Agave americana) exist for a decade or more before flowering and dying

(a) Once

(b) Twice

(c) Thrice

(d) Not countable

  1. Grana stacks of thylakoid membranes are high in

(a) PS-I

(b) PS-II

(d) Chloroplast a (or) b

(c) Cyt b (or) f

  1. In the great majority of plant species, seed germination begins with

(a) Radicle

(b) Epicotyl

(c) Both (a) and (b)

(d) None

  1. Phyllotaxis is related with arrangement of

(a) Roots

(c) Leaves

(b) Branches

(d) Flower

  1. Oxygenase function of Rubisco was first shown by

(a) Andrews and Lorimer

(b) Ogren and Bowes

(c) Guttendge

(d) Went

  1. Major form of carbon transfer in plants is by

(a) Sucrose

(b) Glucose

(c) Fructose

(d) Maltose

  1. The term auxin was first used in 1926 by

(a) Frits Went

(b) Jacobs

(c) Goldsmith

(d) Yabuta

  1. Photorespiration increases at warm temperature due to

(a) Ratio of dissolved chloroplast O₂ to CO₂ is lower

(b) Ratio of dissolved chloroplast O₂ to CO₂ is higher

(c) Ratio of dissolved chloroplast O₂ to CO₂ is not affected

(d) Ratio of dissolved chloroplast O₂ to CO₂ is equal

  1. IAA is chemically similar to the amino acid

(a) Methionine

(b) Tryptophan

(c) Serine

(d) Proline

  1. Apical dominance is the result of

(a) Auxins

(b) Cytokinins

(c) Ethylene

(d) GA

  1. The bakanae (foolish seedling) disease of rice is caused by

(a) Gibberella fujikuroi

(b) Claviceps fuziformi

(c) Xanthomonas oryzae

(d) None

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