Questions: Scientists have uncovered evidence showing that cyanobacteria have been present on Earth over the past 3.5 billion years, yet a single cyanobacterium has a life-span of only a day or two. Which biological principle does this set of observations best illustrate? Cells use matter and energy from the environment to maintain the living state, to grow, and to reproduce. Life is continuous, with successive generations connected in an unbroken chain of transfer of biological information. Cells are the fundamental units of life, and all organisms are composed of cells, All organisms present on Earth today share a common ancestor, Environmental factors can influence the growth and development of an organism.

The answer is the second one: Life is continuous, with successive generations connected in an unbroken chain of transfer of biological information.

Explanation for each option:

1. Cells use matter and energy from the environment to maintain the living state, to grow, and to reproduce.

   • This principle explains how individual cells function and sustain life, but it does not directly address the continuity of life over billions of years despite the short lifespan of individual organisms.

2. Life is continuous, with successive generations connected in an unbroken chain of transfer of biological information.

   • This principle is the most relevant to the question. It explains how life can persist over billions of years through the continuous reproduction and transfer of genetic information from one generation to the next, despite the short lifespan of individual organisms like cyanobacteria.

3. Cells are the fundamental units of life, and all organisms are composed of cells.

   • While this is a true statement, it does not specifically address the continuity of life over long periods of time.

4. All organisms present on Earth today share a common ancestor.

   • This principle speaks to the common origin of all life forms but does not directly explain the persistence of cyanobacteria over billions of years.

5. Environmental factors can influence the growth and development of an organism.

   • This principle is about how the environment affects individual organisms, but it does not explain the long-term continuity of life.

Summary: The principle that best illustrates the observation that cyanobacteria have been present on Earth for 3.5 billion years despite their short individual lifespans is that life is continuous, with successive generations connected in an unbroken chain of transfer of biological information.