In high concentrations, hydrogen sulfide (H₂S) is typically toxic to many plants. Frederick D. Dooley and colleagues wanted to understand what effects low doses of H₂S might have on plant growth. They treated bean, corn, wheat, and pea seeds with various concentrations (measured in micromoles per liter) of H₂S and tracked the germination of those seeds along with the germination of untreated seeds. Treatment with particular concentrations of H₂S was associated with accelerated germination.

Which choice most effectively uses data from the graph to complete the statement?

A. At 168 hours, more than 90% of seeds treated with H₂S at concentrations of 10 or 500 micromoles per liter had germinated, whereas less than 70% of untreated seeds had germinated.

B. At 48 hours, approximately 50% of seeds treated with H₂S at a concentration of 10 micromoles per liter had germinated, whereas only approximately 30% of untreated seeds had germinated.

C. At 24 hours, less than 10% of seeds treated with H₂S at a concentration of 10 micromoles per liter had germinated, whereas more than 90% of those seeds had germinated at 168 hours.

D. At 48 hours, more than 70% of seeds treated with H₂S at a concentration of 10 micromoles per liter had germinated, whereas only approximately 50% of untreated seeds had germinated.

D) at 48 hours, more than 70% of seeds treated with H2S at a concentration of 10 micromoles per liter had germinated, whereas only approximately 50% of untreated seeds had germinated.

Explanation:

This is the best choice. The claim is that some concentrations of H2S led to increased germination rates, and this choice accurately shows that seeds treated with 10 micromoles per liter of H2S tended to germinate faster than untreated seeds.

TealRedmann TealRedmann · Answer 2 · 2023-12-24T15:20:03-05:00

Option B is the correct answer: at 48 hours, approximately 50% of seeds treated with H2S at a concentration of 10 micromoles per liter had germinated, whereas only approximately 30% of untreated seeds had germinated.

Hydrogen sulfide (H2S) is recognized for its toxicity in high concentrations, yet this gas can be found naturally in the atmosphere as a result of various processes involving organic sulfur compounds and can also be released through industrial activities such as wood pulping. Given its toxic nature, it's surprising to learn that H2S can have a stimulatory effect on plant growth at low concentrations. The experiment conducted by Frederick D. Dooley and colleagues illustrates this by treating various seeds including bean, corn, wheat, and pea with different concentrations of H2S and comparing their germination rates to those of untreated seeds. The treatment with H2S indeed accelerated seed germination; specifically, seeds treated with H2S showed higher germination rates than untreated seeds at early time points. This indicates a potential application of H2S in agricultural procedures to enhance germination, though careful handling and consideration of its toxicity is essential. The stimulation of germination suggests that H2S, despite its toxic reputation, may play a complex role in plant physiology at low doses.