NET, IAS, State-SET (KSET, WBSET, MPSET, etc.), GATE, CUET, Olympiads etc.: Botany MCQs (Practice_Test 97 of 104)
Glide to success with Doorsteptutor material for competitive exams : get questions, notes, tests, video lectures and more- for all subjects of your exam.
- Which one of the following plants has dimorphic chloroplasts in its leaves?
- Zea mays
- Triticum aestivum
- Oryza sativa
- Nicotiana tabaccum
- Consider the following events in the photochemical conversion of light energy into chemical energy by chlorophyll during photosynthesis:
- Charge separation
- Absorption of a quantum of energy
- Ejection of electron
- Transfer of light energy
- The correct sequence of these events is
- 4,2, 1,3
- 4,2, 3,1
- 2,4, 1,3
- 2,4, 3,1
- Which one of the following compounds in the photosynthetic electron transport chain contains copper?
- Cytochrome
- Ferredoxin
- Plastoquinone
- Plastocyanin
- On storage, the sweetness of corn is lost due to conversion of soluble sugars into polysaccharide. If corn is immersed after harvest in boiling water and cooled, the sweetness remains because the
- Polysaccharide is re-converted into soluble sugars
- Concentration of sugar increases due to heating
- Conversion of sugars to polysaccharide stops
- Enzymes responsible for the conversion are destroyed
- Which one of the following statements correctly disguises Nitrosamines and Nitrobacter?
- Nitrosamines is nitrifying bacterium whereas Nitrobacteria is a denitrifying bacterium
- Nitrosamines oxidizes ammonia to nitrite while Nitrobacteria oxidizes nitrite to nitrate
- Nitrosamines fixes atmospheric nitrogen into ammonia while Nitrobacteria oxidizes ammonia to nitrate
- Nitrosamines is responsible for amino acid synthesis while Nitrobacteria is responsible for protein synthesis.
- The following compounds are intermediates in the pathway of photorespiration:
- Phosphoglycolate
- Glyxylate
- Serine
- Glycine
- The correct sequence of their appearance in the pathway is
- 1,2, 3,4
- 2,1, 3,4
- 1,2, 4,3
- 2,1, 4,3
- Trios phosphate dehydrogenises in glycol sis and Calvin cycle are NOT exactly identical enzymes because
- These are separated compartmentally
- Glycols takes place both in light and darkness while Calvin cycle does not require light
- In glycol sis, it is NAD-linked, while in Calvin cycle, it is NADP-linked
- In glycol sis it is associated with catabolic reactions, while in Calvin cycle it is associated with anabolism
- A competitive enzyme inhibitor
- Alters the Vmax but does not alter the Km of the enzyme
- Alters the Km but does not alter the Vmax of the enzyme
- Alters both Km and vmax of the enzyme
- Does not alter either the Km or Vmax of the enzyme
- Consider the following statements about enzymes:
- Most enzymes arc pertinacious, although some are RNA molecules.
- The specificity of an enzyme is due to its well-defamed three-dimensional structure and the active site present in it.
- Prosthetic group is loosely bound to the apoenzyme part of the enzyme.
- Portions, prosthetic group and apoenzyme are enzymatic ally inactive when separated from each other.
- Of these statements.
- 1,2 and 3 are correct
- 1,3 and 4 are correct
- 1,2 and 4 are correct
- 2,3 and 4 are correct
- Which one of the following statements about protein synthesis in a eukaryotic cell is true?
- Fornicated tRNA is important for initiation of translation
- Cycloheximide blocks elongation during translation
- Single in mRNAs specify for more than one gene product
- Erythromycin inhibits elongation during translation
- Which of the following statements are true of all tRNAs?
- The 5՚-end is phosphorylated.
- They are single chains.
- The antic Odon loop is identical.
- The 3՚-end base sequence is CCA.
- Select the correct answer
- 1,2 and 3
- 1,3 and 4
- 1,2 and 4
- 2,3 and 4
- The function of end nuclease is to
- Nick the DNA molecule at the terminal end
- Nick the DNA molecule in the middle
- Nick the reverse transcriptase
- Terminate elongation of Okazaki fragments
- To start the transcription process, a specific factor called the sigma (s) factor is required. Its function is to
- Help RNA polymerase to start transcription
- Help binding of RNA polymerase to DNA template
- Help binding of rho (stop) factor
- Act as a stop signal
- RNA is structurally susceptible to chemical and enzymatic degradation because of
- The presence of uracil
- The absence of thymine
- The presence of a hydroxyl group
- Ribofuranose ring structure
- Which one of the following is a secondary metabolite?
- Ribulose
- Glycerol
- Metabolic acid
- Cholesterol