During a school microbiology practical, students prepare agar plates to culture a harmless strain of Bacillus subtilis. The teacher instructs them to incubate their inoculated plates at 25 ∘C25\text{ }^{\circ}\text{C}25 ∘C rather than the bacterium's optimal growth temperature of 37 ∘C37\text{ }^{\circ}\text{C}37 ∘C.
Explain the health and safety reason for incubating the bacterial cultures at this lower temperature.
