Final answer:
Organisms die due to various factors, and their nutrients are recycled back into the environment by decomposers, helping to maintain vital nutrient cycles. Excessive nutrients from human activities can disrupt these cycles, creating dead zones. Cellularly, cell size and shape affect nutrient intake and waste elimination rates.
Step-by-step explanation:
When organisms die, their cells stop functioning and they can no longer maintain life processes, which is a result of factors such as genetic predispositions, environmental stress, disease, and depletion of vital resources. Decomposers play a crucial role by breaking down dead organisms and thus recycling the nutrients back into the environment. In aquatic ecosystems, this recycling process is vital for maintaining the nutrient cycles.
However, if an ecosystem is overloaded with nutrients due to runoff containing excess phosphorus and nitrogen, it can lead to devastating effects such as the formation of dead zones, where depleted oxygen levels result in the death of many organisms.
In a cellular context, during the death phase of a culture, the accumulation of toxic wastes and the exhaustion of nutrients lead to the death of cells. Some cells may lyse and release nutrients, allowing a few surviving cells to persist and maintain viability.
Meanwhile, the overall rate of nutrient intake and the rate of waste elimination are influenced by the size and shape of cells. Smaller cells with a higher surface-to-volume ratio can more efficiently exchange substances with their environment than larger cells with a lower surface-to-volume ratio.