Characteristics Of Living Things: Share 8 Characteristics ✓ Solved

Characteristics Of Living Thingsliving Things Share 8 Characteristics

Characteristics of Living Things Living things share 8 characteristics (listed in Chapter 1 of your textbook on page 19). A living thing grows, undergoes metabolism, responds to its environment, reproduces, passes DNA to the next generation, maintains homeostasis, changes over time, and is made up of cells. A non-living thing may seem to do one or more of these things, but to be classified as living; all eight characteristics must be present. Sometimes, you may see something that seems alive but is not. Though you can’t see it, you have likely experienced it; one of those things is a virus.

Answer BOTH of the following questions: 1. Using all 8 of the characteristics that define life, indicate which one(s) viruses have and which one(s) they do not, and explain each difference. 2. With these results, present an argument that a virus is a living thing. Then, present the opposite argument that viruses are not alive.

Sample Paper For Above instruction

Viruses occupy a unique position in the biological spectrum, raising questions about their classification as living or non-living entities. To explore this, it is essential to evaluate viruses against the eight characteristics that define life: reproduction, passing traits through DNA, consuming energy and maintaining homeostasis, responding to stimuli, changing over time, individual variation within a species, and being composed of cells.

Viruses and the Eight Characteristics of Life

Starting with reproduction, viruses can reproduce, but only within a host cell. Outside a host, they exist as inert particles incapable of independent reproduction. They pass along their genetic material—DNA or RNA—through infection of host cells, thus satisfying the passing of traits characteristic. However, viruses do not actively consume energy sources or expel waste products to maintain homeostasis; they lack metabolic processes entirely.

Regarding response to their environment, viruses can respond indirectly; they may recognize and bind to specific host cell receptors, but they do not respond actively to stimuli in their environment as living organisms do. They do not change over time independently, as evolution occurs across viral populations through mutation, but individual viruses do not evolve or change during their lifespan.

Viruses are not made up of cells. They are composed of genetic material encased in a protein coat called a capsid. Lastly, viruses do not maintain homeostasis, nor do they exhibit growth or change as individuals, and they cannot differ as individuals while being part of a species since they are products of genetic replication.

Arguments Supporting Viruses as Living Organisms

Despite lacking cell structure and metabolic activity, viruses exhibit critical features of life—most notably, reproduction and genetic transmission. They possess genetic material (DNA or RNA) that they pass on to their progeny during replication, aligning with the characteristic of inheritance. Viruses also evolve over time, demonstrating change within populations, which reflects their ability to adapt and survive in changing environments. These aspects parallel the fundamental processes considered essential to life.

Furthermore, viruses have the ability to infect and hijack host cellular machinery, effectively coordinating complex biochemical processes necessary for replication—a trait shared by living organisms. Their capacity for evolution and adaptation further supports their classification as living entities at a biological level.

Arguments Supporting Viruses as Non-Living Entities

Conversely, viruses do not fulfill several criteria defining living organisms. They lack cellular structure, which is fundamental for life, and do not carry out metabolic processes independently. They cannot generate their own energy or carry out waste elimination, making them inert outside of host cells. Without metabolic activity, viruses are essentially dormant particles until they infect a host.

Additionally, individual viruses do not grow, respond to stimuli in a meaningful biological sense, or maintain homeostasis. They do not exhibit any of these behaviors on their own, which is a core criterion for life. Their dependence on host cells to reproduce and carry out life processes indicates they are more akin to molecular parasites rather than autonomous living organisms.

Conclusion

In summary, viruses demonstrate some characteristics of life, such as genetic inheritance and evolution over time, but lack key features like metabolism, cell structure, and independent response to stimuli. This duality has led many scientists to classify viruses as non-living entities that occupy a gray area in biological classification. The debate continues, focusing on whether the defining features of life should include internal metabolic processes and cellular complexity or whether genetic transmission and adaptability suffice for classification as living organisms.

References

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