Question

what is a significant impact of deforestation on ecosystems? a. decreasing carbon dioxide levels b. disrupting habitats and reducing biodiversity c. encouraging biodiversity d. enhancing oxygen balance how do ecosystems contribute to nutrient cycling? a. by isolating different species from one another b. by limiting the growth of plant species c. through the continuous movement of elements like carbon and nitrogen d. by absorbing pollutants and increasing soil erosion what characterizes commensalism in symbiotic relationships? a. one benefits, the other is harmed b. both species are harmed c. one benefits, the other remains unaffected d. both species benefit

Explanation:

1. Deforestation destroys the natural habitats of many species, leading to a reduction in biodiversity. Trees also absorb carbon - dioxide, and deforestation increases carbon - dioxide levels, not decreases them. It disrupts oxygen - carbon dioxide balance negatively and does not enhance oxygen balance.
2. Nutrient cycling in ecosystems occurs through the continuous movement of elements such as carbon, nitrogen, phosphorus, etc. among different components like soil, plants, animals, and the atmosphere. Isolating species or limiting plant growth does not contribute to nutrient cycling, and increasing soil erosion is not related to positive nutrient - cycling contributions.
3. In commensalism, one organism benefits while the other is neither helped nor harmed. When one benefits and the other is harmed, it is parasitism. When both are harmed, it is amensalism. When both benefit, it is mutualism.

Answer:

1. B. Disrupting habitats and reducing biodiversity
2. C. Through the continuous movement of elements like carbon and nitrogen
3. C. One benefits, the other remains unaffected