Chlorella

This is a tiny green plant.

It is made of very small cells. The cells are round like balls. They are a bright green color.

These plants need water and sunlight to grow. They also need air and minerals. The sunlight helps them make food.

One cell can split into many new cells. This helps them grow fast. They can even live in groups.

Some people take this plant in pills.

It can even help make the air we breathe.

Chlorella is a type of tiny green algae.

It is made of very small, round cells. These cells do not have tails to swim. They use a green part called a chloroplast to make food. This process uses sunlight, water, and carbon dioxide. This way of making food is called photosynthesis. Chlorella is very good at this. It can be even better than crops like sugar cane.

To grow, Chlorella cells go through a set of steps. First, the cells grow larger. Next, they get ready to split. Then, the cell divides into two, four, or eight new parts. These parts are called autospores. The old cell wall breaks open. This lets the new cells out to grow.

In the past, scientists thought Chlorella could end world hunger. They hoped it could be a cheap food for everyone. But growing it in large amounts is hard. It needs special light and expensive water to work well. It also has a very tough cell wall. This makes it hard for humans to digest. Today, many people take it in pills.

Some companies say it can treat diseases. However, the American Cancer Society says studies do not support this.

Chlorella is a group of about thirteen species of tiny green algae. These algae are made of single cells or small groups called colonies. Each cell is shaped like a tiny ball or an oval. They are very small, measuring only 2 to 10 micrometers across. These cells do not have tails to swim through the water. Instead, they use green parts called chloroplasts to make food. These parts contain pigments called chlorophyll-a and chlorophyll-b. This helps them use sunlight to grow.

To make more cells, Chlorella follows a specific way of working. This way of working is called asexual reproduction. First, the cells enter a growth phase to get bigger. Next, they enter a ripening phase to prepare for splitting. During the post-ripening phase, the cell contents divide into two, four, or eight parts. These new parts are called autospores. Eventually, the old cell wall breaks open to release them. Once released, each new cell grows into its own individual.

Many famous scientists have studied this tiny green algae. Martinus Beijerinck first described Chlorella in 1890. Later, Otto Heinrich Warburg studied how these cells breathe. He won a Nobel Prize in 1931 for his work. In 1961, Melvin Calvin also won a Nobel Prize. He studied how Chlorella uses carbon dioxide to grow. These scientists helped us understand how such small things work. Their research showed how important photosynthesis is to life.

Chlorella has a very interesting history with human food. In the 1940s and 1950s, people worried about world hunger. Experts thought Chlorella could be a cheap way to feed everyone. Some tests showed it could turn 20% of solar energy into food. It can also contain 50% protein when dried. However, growing it in large amounts proved to be a hard job. It needs special light and expensive carbonated water to work best. Its cell walls are also very tough for humans to digest.

Today, you might see Chlorella in a different way. Many people take it as a dietary supplement in pill form.

Some companies claim these pills can treat diseases like cancer. However, the American Cancer Society says studies do not support this. The government has even warned companies about making these false claims. Even so, Chlorella remains a fascinating part of our natural world. It shows how much we can learn from tiny living things.

Chlorella is a genus of approximately thirteen species of green algae. These organisms belong to the division Chlorophyta. They can exist as single cells or as small groups called colonies. Each cell is shaped like a sphere, a subsphere, or an ellipsoid. They are very small, measuring only 2 to 10 micrometers in diameter. These cells lack flagella, which are tiny tail-like structures used for swimming. Instead, they rely on specialized parts to survive and grow.

Inside each cell, a single chloroplast performs the work of photosynthesis. The chloroplast is parietal, meaning it lies against the inner side of the cell membrane. This organelle contains green pigments known as chlorophyll-a and chlorophyll-b. Within the chloroplast, a single pyrenoid is surrounded by grains of starch. To reproduce, Chlorella uses a process called autosporulation. This is a form of asexual reproduction where the cell contents divide into two, four, or eight protoplasts. These new units are called autospores. Eventually, the parent cell wall ruptures to release them.

Researchers have identified four specific phases during asexual reproduction in Chlorella ellipsoides. First is the growth phase, where cells increase in size using photosynthetic products. Next is the ripening phase, where cells mature for division. The third is the post-ripening phase. During this stage, a mature cell divides twice, either in light or in the dark. Cells formed in the dark are called dark-to-light phase cells, and they grow in size again. Finally, the division phase occurs when the parent cell wall ruptures to release the unicells. Sulfur is considered essential for this cell division to happen.

Many Nobel Prize-winning scientists have studied Chlorella to understand life. Martinus Beijerinck first described the genus in 1890. In 1931, Otto Heinrich Warburg won the Nobel Prize in Physiology or Medicine for his research on cell respiration. Melvin Calvin later won the Nobel Prize in Chemistry in 1961. He used Chlorella to study the pathways of carbon dioxide assimilation in plants. These studies helped scientists understand how plants turn gas into food. Chlorella also exists in symbiosis with other living things. Certain strains, like K10, live inside the animal Hydra viridissima.

In the mid-20th century, Chlorella was viewed as a potential solution to world hunger. Following World War II, there were fears of a massive human population boom. In 1946, a report suggested the world would need much more food by 1960. Some scientists thought Chlorella could be a highly efficient primary food source. Initial tests at the Stanford Research Institute showed it could convert 20% of solar energy into biomass. When dried, the algae could contain 50% protein. One scientist even predicted that a 1,000-acre farm could produce 10,000 tons of protein annually using only 20 workers.

However, large-scale production proved to be much more difficult than expected. To reach maximum efficiency, the algae required artificial light or shade. Growing it at high productivity required expensive carbonated water. Scientists also discovered that the cell walls were too tough for humans to digest easily. After a decade of study, researchers found it captured only 2.5% of solar energy in sunlight. This was not much better than conventional crops. Because of these high costs and technical hurdles, Chlorella never became a major global food source like soybeans or grains.

Today, Chlorella is mostly used as a niche dietary supplement.

It is sold in various forms, including pills. Some companies have falsely claimed it can treat diseases like cancer. The American Cancer Society states that studies do not support these claims. The U.S. Food and Drug Administration has issued warnings to companies making these false advertisements. Despite this, Chlorella remains important in other areas. For example, the Russian BIOS-3 experiment found that 8 square meters of Chlorella could replace oxygen for one human in a sealed environment. It remains a vital subject for studying how organisms manage carbon dioxide and oxygen.