MCQs Botany-40 Posted on October 27, 2025December 3, 2025Author agropublishers 0 MCQs Botany-40 1. Which of the following nitrogenous bases is NOT found in DNA? Guanine Uracil Adenine Thymine 2. During photosynthesis, energy is converted from ___ energy into ___ energy, stored in the bonds of glucose Mechanical; Light Kinetic; Chemical Chemical; Chemical Light; Chemical 3. What term describes a large, naturally occurring community of plants and animals that occupy a specific habitat, such as a forest, desert, or ocean? Niche Ecosystem Habitat Biome 4. The central dogma of molecular biology describes the flow of genetic information as________ Protein → DNA → RNA DNA → RNA → Protein DNA → Protein → RNA RNA → DNA → Protein 5. Roots are absent in _________ Angiosperms Gymnosperms Pteridophytes Bryophytes 6. In plants true roots first evolved among _________ Pteridophytes Angiosperms Gymnosperms Bryophytes 7. Oxygen generally composed of _______ of biomolecules in living organisms 40% 18% 35% 65% 8. Non-coding RNAs, such as microRNAs (miRNAs), can be considered part of epigenetic regulation because they___________ Regulate gene expression at the post-transcriptional level without altering the DNA sequence Are the primary components of chromatin Directly repair DNA damage Code for histone proteins 9. 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? Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) Phosphoribulokinase (PRK) Sedoheptulose-1,7-bisphosphatase (SBPase) Fructose-1,6-bisphosphatase (FBPase) 10. 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 Loading … Question 1 of 10
