Subject

Life Sciences

Class

CNET Class 12

Pre Boards

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Sample Papers

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 Multiple Choice QuestionsMultiple Choice Questions

101.

The oxidative pentose phosphate pathway provides the reducing equivalents for nitrite reduction in plastics (leucoplasts) of non-green plants. Which one of the following statements would be correct for the above mentioned pathway?

  • Glutamate synthesized from NH4+ is translocated from the cytosol to the leucoplast.

  • α-ketoglutarate is translocated from cytosol to leucoplast.

  • Glucose-6-phosphate is translocated and moves from leucoplast to cytosol.

  • Triose phosphate is translocated from cytosol to leucoplast.


102.

Perception of blue light n plants causes

  • inhibition of cell elongation and stimulation of stomatal opening

  • stimulation of cell elongation and inhibition of stomatal opening

  • inhibition of stomatal opening

  • inhibition of cell elongation


103.

The following are few statements regarding the water potential of soil.

(A) The osmotic potential (ψs) of soil water is generally negligible, except in saline soils.

(B) The osmotic potential (ψs) of saline soil is always more than zero.

(C) In dry soils the hydrostatic pressure (ψp) of soil water potential is always positive.

(D) Gravitatinal potential (ψg) of soil water is always proportional to height of the tree.

Which one of the following combinations of above statements is true?

  • (A) and (C)

  • (B) and (D)

  • (C) and (B)

  • (D) and (A)


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104.

Which one of the following pairs of precursors amino acid and alkaloid is correct?

  • 'Ornithine aspartate-nicotine' and trptophan -quinone'

  • 'Ornithine-nicotine' and 'tyrosine-orphine' 

  • 'Tyrosine-quinone' and 'tryptophan-orphine'

  • 'Ornithine-quinine' and 'ornithine-aspartate-nicotine'


A.

'Ornithine aspartate-nicotine' and trptophan -quinone'

Ornithine aspartate-nicotine and tryptophan- quinone are the precursor of amino acid and alkaloid.


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105.

Typical morphological defects are routinely used in genetic screens to identify novel genes in signal transduction pathways. Which one of the following morphology has been used to decipher the ethylene signaling pathways?

  • Light grown morphology of seedling

  • Tripple response morphology of seedling

  • Dark grown morphology of seedling

  • Morphology of true leaves


106.

In bone marrow, stem cells are committed to different lineages. Factors that stimulate the colonies of these different lineages are interleukin-3 (multi-CSF), granulocyte-macrophage colony-stimulating factor (G-CSF or M-CSF). In a mouse deficient in GM-CSF, the number of hematopoietic cells will be altered. Which one of the following is correct?

  • Mast cells will be normal in normal while granulocytes and macrophages will be deficient in number.

  • Granulocytes count will be normal but not of macrophages

  • Macrophage number will remain unaltered.

  • Mice will be deficient in all the three cell types.


107.

An individual was suffering from digestive complications. It was observed that the individual had a dehydrated gastrointestinal tract. When an advanced investigation was done, the person was found to have defects in the following:

(A) cystic fibrosis transmembrane conductance regulator protein.

(B) glucose transporter protein

(C) Na+/ K+ ATPase

(D) Ca2+ ATPase

Which of the above could be the cause for such a digestive disorder?

  • (A) only

     

  • (B) and (C)

  • (C) and (D)

  • (D) only


108.

The action potential was recorder intracellularly from a squid giant axon bathed in two types of fluid such as sea water and artificial sea water having lower concentration of sodium ions while maintaining the same osmotic pressure with chlorine chloride. The nature of action potential was different in the two bathing fluids. Which of the following  results is most likely?

  • The resting transmembrane potential was not changed but the amplitude of action potential was increased with lower sodium concentration in the bathing fluid.

  • The amplitude of action potential was gradually decreased with reduction of sodium concentration in bathing fluid but the duration of action potential was prolonged.

  • The resting transmembrane potential was decreased and the amplitude of action potential and the amplitude of action potential was also decreased with lower sodium concentration in the bathing fluid.

  • The amplitude of action potential was not changed with reduction of sodium concentration in the bathing fluid but the duration of action potential was prolonged.


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109.

Three forms of dextrans namely neutral, polyanionic and polycationic having different molecular radii were injected separately in three groups of rats. The concentrations dextrans in glomerular filtrate were measured to determine the filterability of the dextrans. The possible outcomes could be as follows:

(A) The dextrans having smaller diameter have greater filterability than large dextrans.

(B) Neutral dextrans were filtered more than polycationic and polyanionic dextrans.

(C) Polycationic dextrans were filtered more than neutral and polyanionic dextrans.

(D) Polyanionic dextrans were filtered more than neutral and polycationic dextrans.

Which one of the following combinations is correct?

  • (A) only

  • (B) only

  • (A) and (C)

  • (B) and (D)


110.

A novel enzyme was identified in humans. The following approaches are available to identify the chromosome on which the gene encoding the enzyme is present:

(A) Suppress the activity of enzyme by RNAi.

(B) Identify polymorphism in the population and carry out pedigree analysis to study its inheritance.

(C) Purify the enzyme, decipher its amino acid sequence, predict its DNA sequence and search for its presence in the available human genome sequence.

(D) Create chromosome addition lines by making somatic hybrids between human and mouse cells, identify lines showing the enzyme and the human chromosome present in it.

Which of the above approaches can be used?

  • (A) or (B)

  • (B) or (C)

  • (C) or (D)

  • (A) or (C)


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