Bioelectrogenesis (bioelectricity)

Bioelectrogenesis, which is also called bioelectricity, is the production of electricity by a living organism. Bioelectrogenesis is present in nearly all living creatures. Although most living organisms do not give off enough electricity to be noticed by a casual observer, electrical pulses help living things think and move. Some creatures have developed much stronger forms of bioelectricity. These animals, mostly creatures that live in the water, can discharge electric currents into their environment. They do this mostly to protect themselves from predators and to catch prey.

Background

The production of electricity inside a living organism is important for life. Various cells inside living things produce electricity. The electricity inside a living creature, such as a human, can move to other cells thanks to certain biochemical conditions. Human bodies are made up mostly of water, and water is a good conductor of electricity. Furthermore, the water in the body is full of dissolved salts, which also help conduct electricity. The salts in the human body are often ions with positive and negative charges. These positive and negative charges help pass the electrical impulses in the body.

The generation of electricity occurs in the cells of the bioelectric organisms. Although an animal that generates electricity might not be creating the electricity all the time, the cells inside the organism do not "turn off." Instead, they are constantly ready to transmit the electronic pulse. Many different types of cells can support membrane voltage. This membrane can send small electronic pulses from the cell to other cells. These tiny electrical impulses help people and animals think and move. They are very important in animal life. Neurons are specialized cells in the brain. They send electrical impulses through biochemical processes.

Medical professionals can measure bioelectricity in humans. The electroencephalogram (EEG) is a test that detects electrical activity in the brain. Neurons in the brain transfer electrical impulses, and the EEG can identify these impulses. Another test, the electrocardiogram (ECG or EKG), measures the electrical impulses in the heart. The cells in the heart send electrical impulses that help move the muscle that is the heart. With each heartbeat, a wave of electricity passes through the heart. The EKG measures these waves of electricity. The EEG and EKG are important because medical professionals can detect some health problems if they notice irregularities in the bioelectric impulses in the brain or heart.

Overview

Although most living things produce electricity on some level, only some types of animals have developed bioelectrogenesis at the organism level. That is, the animal has special body parts that emit larger voltages of electricity. The electricity passes from inside the animal into its surroundings. Many of the animals that produce electricity through their organs live in the water. Water is a much better conductor of electricity than air, so the electricity passes into other living things around the animals. These animals have special cells called electrocytes. These cells are excitable, and they are the cells that generate the electricity inside the animals' organs. The electrocytes also use dissolved salt ions to help create the electricity.

These animals use their bioelectricity to protect themselves from predators and to stun and catch prey. Some fish also use electricity to sense prey, to observe their environment, and to communicate with other fish. Scientists believe that different types of fish evolved the organs that create bioelectricity at different times. That means that this biological characteristic is most likely very helpful since different animals evolved to have similar abilities.

One of the most famous examples of an organism that has organs that produce electricity is commonly called the electric eel. Despite its name, the fish is a type of knife fish and not a true eel. This fish can grow to be six feet long and can discharge a current of up to five hundred volts. These long fish have special organs that help them produce the electricity. These organs take up large portions of their bodies. When hunting, the fish will create a small electric field around itself. The electric field helps it locate and identify prey. The eel then swims next to the prey and discharges a charge of about five hundred volts to stun and incapacitate its prey. This is a powerful electric current that would stun an adult human. Once the prey is incapacitated by the shock, the fish will eat it.

Another animal known for its bioelectricity is the electric ray, which is sometimes called the torpedo ray. These rays often stay near the bottom of the ocean floor during the day. They hide in the sand. If a fish gets close enough to it, the ray will discharge a current of electricity strong enough to stun the prey. Then, the ray eats it. Although these fish do not create a strong enough voltage to kill a person, the rays are not afraid of people in part because of their powerful defense mechanism. These rays discharge the electric current through two glands on either side of their heads.

Scientists are using elements of bioelectrogenesis in their work. After studying the electric eel, some scientists attempted to make a battery based on the bioelectrogenesis observed. The scientists planned to create a battery using cells and sugars to generate electricity in a way that would be similar to the way the fish produces electricity. The scientists interested in making these new types of batteries hoped that their work would improve solar panels and other technologies. The ideas for bio-batteries could make important advances in technology in the future.

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