Chapter 15, Problem 17STP

Summary Introduction

To explain:

The reason behind the belief that understanding the origin of life on Earth would help with discovering life on other planets.

Introduction:

Scientists Stanley Miller and Harold Urey were the first to show that simple organic molecules could be made from inorganic compounds. Many experiments were conducted under conditions that were similar to the atmosphere of early Earth. Scientists studied life existing in harsh conditions such as hot springs and volcanic vents.

Answer to Problem 17STP

Knowledge about origin of life on Earth would help with discovering life on Earth as well as on other planets. By studying about organisms living in deep ocean hypothermal vents and hot springs, scientists tried to understand how life could have evolved in early Earth and other planets as these conditions were similar to the atmosphere of the early earth.

Explanation of Solution

The hot spring at Yellowstone National Park and the volcanic vents have an environment similar to the environment of early Earth. It is believed that early Earth had very high temperatures due to colliding meteorites, compression of minerals and decay of radioactive materials. Volcanoes were frequently releasing gases and lava. Gases like ammonia, methane and hydrogen formed the early atmosphere and it lacked free oxygen.

Scientists hypothesize that prokaryotes were the first cells to have occurred on Earth. Many scientists think that modern prokaryotes called archaebacteria are the closest relatives of Earth’s first cells. These organisms live in extreme conditions such as the hot springs of Yellowstone National Park.

By studying these organisms, scientists concluded that life on early Earth could have started with these prokaryotes. Perhaps this could also throw some light on life on other planets as the conditions are similar to that on early Earth.