Class 10 Biology



Life Processes

Exemplar Problems Solutions MCQ III

Which of the following is an incorrect statement?

  • Organisms grow with time
  • Organisms must repair and maintain their structure
  • Movement of molecules does not take place among cells
  • Energy is essential for life processes

    Answer:(c) Movement of molecules does not take place among cells

The internal (cellular) energy reserve in autotrophs is

  • Glycogen
  • Protein
  • Starch
  • Fatty acid

    Answer: (c) Starch [Plants store food in the form of starch]

Choose the event that does not occur in photosynthesis

  • Absorption of light energy by chlorophyll
  • Reduction of carbon dioxide to carbohydrates
  • Oxidation of carbon to carbon dioxide
  • Conversion of light energy to chemical energy

    Answer: (c) Oxidation of carbon to carbon dioxide [Reduction of carbon dioxide releases oxygen which is utilised for making carbohydrates.]

The opening and closing of the stomatal pore depends upon

  • Oxygen
  • Temperature
  • Water in guard cells
  • Concentration of CO2 in stomata

    Answer: (c) Water in guard cells [Entry of water in guard cells results in opening of stoma and reverse of it results in closing of stoma.

Choose the forms in which most plants absorb nitrogen

  • Proteins
  • Nitrates and Nitrites
  • Urea
  • Atmospheric nitrogen
    • (1) and (2)
    • (2) and (3)
    • (3) and (4)
    • (1) and (4)

      Answer: (b) (2) and (3) [Protein is made by plants by utilising nitrogen. Plants cannot take up atmospheric nitrogen.]

Which is the first enzyme to mix with food in the digestive tract?

  • Pepsin
  • Cellulase
  • Amylase
  • Trypsin

    Answer: (c) Amylase [salivary amylase from saliva is the first enzyme to mix with food.]

Which of the following statement(s) is (are) correct?

  • Pyruvate can be converted into ethanol and carbon dioxide by yeast
  • Fermentation takes place in aerobic bacteria
  • Fermentation takes place in mitochondria
  • Fermentation is a form of anaerobic respiration
    • (1) and (3)
    • (2) and (4)
    • (1) and (4)
    • (2) and (3)

      Answer: (c) 1 and (4) [Fermenation is a form of anaerobic respiration whic takes place in cytoplasm and liberates ethanol/lactic acid and carbon dioxide.]

Lack of oxygen in muscles often leads to cramps among cricketers. This results due to

  • Conversion of pyruvate to ethanol
  • Conversion of pyruvate to glucose
  • Non conversion of glucose to pyruvate
  • Conversion of pyruvate to lactic acid

    Answer: (d) Conversion of pyruvate to lactic acid [Accumulation of lactic acid in muscles results in muscle cramps.]

Choose the correct path of urine in our body

  • kidney → ureter → urethra → urinary bladder
  • kidney → urinary bladder → urethra → ureter
  • kidney → ureters → urinary bladder → urethra
  • urinary bladder → kidney → ureter → urethra

    Answer: (c) kidney → ureters → urinary bladder → urethra

During deficiency of oxygen in tissues of human beings, pyruvic acid is converted into lactic acid in the

  • Cytoplasm
  • Chloroplast
  • Mitochondria
  • Golgi body

    Answer: (a) Cytoplasm [Lactic acid is formed after anaerobic respiration in muscle cells and this happens in cytoplasm.]

Which of the following shows the correct equation for photosynthesis?

  • 6CO2 + 12H2O → C6H12O6 + 6CO2 + 6H2O
  • 6CO2 + H2O + Sunlight → C6H12O6 + O2 + 6H2O
  • 6CO2 + 12H2O + Chlorophyll + Sunlight → C6H12O6 + 6O2 + 6H2O
  • 6CO2 + 12H2O + Chlorophyll + Sunlight → C6H12O6 + 6CO2 + 6H2O

    Answer: (c) 6CO2 + 12H2O + Chlorophyll + Sunlight → C6H12O6 + 6O2 + 6H2O



Exemplar MCQ1

Exemplar MCQ2

Exemplar Short Answer 1

Exemplar Short Answer 2

Exemplar Short Answer 3

Exemplar Long Answer

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