MCQs Botany-40 Posted on October 27, 2025December 3, 2025Author agropublishers 0 MCQs Botany-40 1. Roots are absent in _________ Angiosperms Bryophytes Pteridophytes Gymnosperms 2. The central dogma of molecular biology describes the flow of genetic information as________ Protein → DNA → RNA DNA → RNA → Protein RNA → DNA → Protein DNA → Protein → RNA 3. The regulation of the Calvin Cycle involves several key mechanisms. The light-activated enzyme Ferredoxin-Thioredoxin System (Fd-Trx system) reduces disulfide bridges on target enzymes. Which of the following enzymes is NOT activated by this reduction? Fructose-1,6-bisphosphatase (FBPase) Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) Phosphoribulokinase (PRK) Sedoheptulose-1,7-bisphosphatase (SBPase) 4. What is the defining characteristic of imprinted genes? They have an exceptionally high rate of spontaneous mutation Their expression is determined by their parental origin, leading to monoallelic expression They code for the enzymatic machinery involved in epigenetic silencing They are permanently inactivated in all cells of the body 5. Which of the following nitrogenous bases is NOT found in DNA? Uracil Adenine Thymine Guanine 6. What term describes a large, naturally occurring community of plants and animals that occupy a specific habitat, such as a forest, desert, or ocean? Biome Ecosystem Habitat Niche 7. Oxygen generally composed of _______ of biomolecules in living organisms 18% 65% 35% 40% 8. During photosynthesis, energy is converted from ___ energy into ___ energy, stored in the bonds of glucose Chemical; Chemical Light; Chemical Mechanical; Light Kinetic; Chemical 9. Non-coding RNAs, such as microRNAs (miRNAs), can be considered part of epigenetic regulation because they___________ Code for histone proteins Are the primary components of chromatin Directly repair DNA damage Regulate gene expression at the post-transcriptional level without altering the DNA sequence 10. In plants true roots first evolved among _________ Pteridophytes Angiosperms Bryophytes Gymnosperms Loading … Question 1 of 10