Chapter 15, Problem 14STP

Summary Introduction

To infer:

The benefit a primitive cell would get from a symbiotic relationship with a mitochondrion

Introduction: The endosymbiont theory was proposed by Lynn Margulis. In 1966, Margulis proposed that the ancestors of eukaryotic cells lived in association with prokaryotic cells. In some cases prokaryotes might have lived inside eukaryotes. Prokaryotes might have entered as undigested prey or could have been internal parasites. Eventually the relationship became mutually beneficial and prokaryotic symbionts became organelles in eukaryotic cells.

Answer to Problem 14STP

The primitive cell got chemical energy from mitochondria as a result of symbiotic relation with them.

Explanation of Solution

The endosymbiont theory proposed by Lynn Margulis suggests that an early eukaryotic cell or a primitive cell might have been parasitized by or ingested some aerobic prokaryotes. The aerobic prokaryotes established symbiotic relationship with the primitive cell. The prokaryotes got protection from the cell and in return the cell got chemical energy from them. The aerobic prokaryotes, over millions of years became mitochondria. They were no longer able to live on their own. So they became organelles (mitochondria) within all eukaryotic cells.