Problem 3 - Campbell Biology

Question

Which of these best demonstrates unity among organisms? (A) emergent properties (B) descent with modification (C) the structure and function of DNA (D) natural selection

Step-by-Step Solution

Answer

Option C - The structure and function of DNA.

Step 1: Define Unity Among Organisms

Unity among organisms refers to the characteristics or aspects that are shared amongst all living beings, showing commonalities or a shared lineage.

Step 2: Analyze Option A - Emergent Properties

Emergent properties are characteristics that arise from the interactions and synergistic phenomena of simpler components within a system. While important, they do not specifically demonstrate unity among organisms as they can occur in many different contexts, not just biological ones.

Step 3: Analyze Option B - Descent with Modification

Descent with modification is a fundamental concept in evolutionary biology that describes how species change over generations, passing down traits but also modifying them. This implies a shared ancestry among all organisms, which aligns with the idea of unity.

Step 4: Analyze Option C - The Structure and Function of DNA

The structure and function of DNA are nearly universal among organisms and provide a powerful demonstration of unity, as DNA carries the genetic information that is used for the growth, development, and reproduction of all known living organisms.

Step 5: Analyze Option D - Natural Selection

Natural selection is a mechanism by which populations evolve, favoring traits that improve survival and reproduction. It explains diversity more than unity, as it leads to different adaptations in different environments.

Step 6: Conclusion

Out of the given options, the structure and function of DNA best demonstrate unity among organisms because DNA is a common thread underlying the biology of all living things.

Key Concepts

Emergent Properties

Emergent properties refer to characteristics that arise when simpler entities interact to form more complex systems. These properties are not present in the individual components but manifest through the interactions of these components. For example, the human brain's ability to think and process information is an emergent property of the network of neurons.
Emergent properties can be observed in various contexts, such as in ecosystems, where the interaction between different species leads to a balanced environment. Although fascinating, emergent properties are not exclusive to living organisms and do not necessarily demonstrate unity among them.
In a biological context, emergent properties are seen when cells combine to form tissues, organs, and ultimately organisms. Each level of organization displays new properties and functions that are not found in the simpler levels below.

Descent with Modification

Descent with modification is a core principle of evolutionary biology. It explains how species evolve over time through genetic changes across generations. This concept suggests that all organisms share a common ancestor and have diverged through adaptations to their respective environments.
Key elements of descent with modification include:

• Genetic inheritance: Traits passed down from parent to offspring.
• Mutations: Random changes in DNA that introduce new traits.
• Natural selection: The process by which advantageous traits become more common in a population.

This illustrates the unity among organisms, as all life forms can trace their lineage back to a common origin. It highlights the shared ancestry and genetic connections among different species.