MCQs Biology-20 Posted on November 27, 2025December 3, 2025Author agropublishers 0 MCQs Biology-20 1. Toxicology studies ———– Protein synthesis DNA replication Harmful effects of chemicals on organisms Beneficial chemicals 2. The discovery of mustard gas as a mutagen was significant because it showed that __________. Chemicals could also induce heritable genetic changes Radiation was the only mutagenic agent Mutations could not be induced artificially Mutations were always lethal 3. The number of crossovers per bivalent depends on ——– Cell size Chromosome size Centriole number Cytoplasmic volume 4. Recombinant DNA technology is primarily used in ———– Molecular cloning Fossil analysis Anatomy studies Ecosystem monitoring 5. Microscopic gaps between the endings of one neuron and another cell are called__________ Pores Nodes Synapses Transmitters 6. Rhizobium is an example of ———–bacteria Symbiotic nitrogen-fixing Saprophytic Chemosynthetic Parasitic 7. Which example cannot describe a sample? 105 plants chosen from a field All plants in the field 12 leaves measured from one tree 25 students chosen randomly 8. A protoplast is best defined as _____________ A plant cell, after removing its cell wall, containing the plasma membrane and all cellular contents it surrounds A plant cell with its cell wall removed The living part of a cell, including the cytoplasm and nucleus The plasma membrane and all cellular contents it surrounds Loading … Question 1 of 8
