WHAT ARE PHOTOSYNTHETIC ORGANISMS? - BIOLOGY - 2025

The photosynthetic organisms are those able to capture solar energy and use it for the production of organic compounds. This energy conversion process is known as photosynthesis.

These organisms are capable of making their own food using solar energy. These include higher plants, some protists, and bacteria, which can convert carbon dioxide to organic compounds and reduce it to carbohydrates.

The energy necessary for this process to occur comes from sunlight, which promotes the activity of photosynthetic organisms for the production of organic compounds and carbohydrates, which are used by heterotrophic cells as an energy source.

It is important to note that most of the foods consumed daily and the fossil fuel found in nature are products of photosynthesis.

Photosynthetic organisms are considered primary producers within the trophic chain, since among them are those that produce oxygen, which are green plants, algae and some bacteria.

But there are also organisms that are photosynthetic and do not produce oxygen, among these are purple sulfur bacteria and green sulfur bacteria.

What is photosynthesis and what are photosynthetic organisms?

Photosynthesis is the process by which plants, some algae and bacteria are capable of producing glucose and oxygen, taking carbon dioxide and water from the environment. The energy required for this process to occur comes from sunlight.

Photosynthesis. Education. (sf). Image via photosynthesiseducation.com

As can be seen in the image, the plant takes carbon dioxide from the environment, and with the participation of sunlight and water, returns oxygen to the environment.

Upper floors

Higher plants are plants that are known as vascular plants or tracheophytes, since they have tissues for the conduction of water through them and others that allow the passage of photosynthesis products.

These plants have structures in their leaves called chloroplasts, which have a pigment called chlorophyll, they absorb sunlight and are responsible for photosynthesis to occur.

Higher plants, as well as some types of bacteria, are called primary producers, since they are capable of producing organic matter such as glucose, splitting inorganic matter (carbon dioxide) through the process of photosynthesis.

These producers are called autotrophic organisms and represent the starting point for the circulation of nutrients and energy in the trophic chain, since the carbohydrates and other chemicals that they produce serve as food for the primary consumers, which are herbivores.

Algae

Like higher plants, these organisms are eukaryotes, that is, they are organisms whose cells have a nucleus and organelles within their membranes. Many of these algae are single-celled, but can occasionally form large colonies and behave like plants.

Among the structures that these eukaryotic organisms have, there are chloroplasts, which are organized subunits whose main role is to carry out the process of photosynthesis, which, as in plants, chlorophyll captures the energy from sunlight to convert it and store it.

Cyanobacteria

Cyanobacteria are prokaryotic organisms, this means that they are unicellular organisms that do not have a nucleus, but they can behave the same as organisms that carry out photosynthesis.

Although they do not contain organelles like the cells of algae, they have a double external system and an internal system with a thylakoid membrane, so they can carry out photosynthesis.

These organisms can produce oxygen from their photosynthetic reactions, because they use water as an electron donor, unlike other bacterial organisms, which carry out a type of photosynthesis called anoxygen.

Sulfur purple bacteria

They are organisms with a very versatile metabolism, since they can use a variety of compounds to obtain electrons and although they do not produce oxygen in their photosynthetic reactions, they have no problem to survive if oxygen is not present.

In the event that environmental conditions favor the change of their metabolism to a photosynthetic way of life, they begin to add more layers to their cytoplasmic membrane system, so that it later becomes an intracytoplasmic membrane, which is necessary for photosynthesis occurs.

Sulfur green bacteria

This type of bacteria does not have mobility, but can have multiple forms, among which are the spiral, spheres or rods. They are located at the bottom of the oceans and survive the lack of light and warm wind.

These bacteria carry out the photosynthesis process in their plasma membrane, without causing any additional alteration to it, since they have vesicles to adjust their depth and thus achieve better illumination and use sulfur as an electron donor, their photosynthesis is anoxic.

Heliobacteria

They are anoxygenic phototrophic bacteria whose discovery is recent. They contain bacteriochlorophyll g, which is a unique pigment for its species, which allows it to absorb different frequencies unlike other photosynthetic organisms.

They are Gram-positive bacteria and the only one of them able to perform phototrophy. They are also capable of forming endospores. They are photoheterotrophic, since they obtain energy from sunlight, but carbon is taken exclusively from organic sources, and they are also anaerobic.

It should be taken into account that life on earth depends mainly on solar energy, which is transformed into glucose and oxygen through the process of photosynthesis, which is responsible for the production of all organic matter.

This organic matter is present in the composition of food consumed daily, in fossil fuels such as oil, in trees and in raw materials used in industries.

The process of photosynthesis is necessary for life to exist on earth, since without the production of oxygen that is secreted through the pores of plant leaves, it is unlikely that the metabolism of animals can take place. cape.

That is why it is said that photosynthesis is a process that has far-reaching implications, because like plants, humans and other animals depend on the glucose that is generated in this process as a source of energy. Hence the importance of photosynthetic organisms.

References

1. Bailey, R. (2016). Photosynthetic Organisms. Retrieved from biology.about.com.
2. Eschool today. (2016). Photosynthesis. Retrieved from eschooltoday.com.
3. Watson, D. (2014). The Flow of Energy Through Plants and Animals. Retrieved from ftexploring.com.
4. Roose, J. (nd). Photosynthesis: Not just for plants. New Under The Sun Blog. Retrieved from newunderthesunblog.wordpress.com.
5. Photosynthesis Education. (sf). Photosynthesis in Bacteria. Retrieved from photosynthesiseducation.com.
6. Asao, Marie, and Madigan, Michael T. (2010). In: eLS. John Wiley & Sons Ltd, Chichester. Retrieved from els.net.
7. Encarta Encyclopedia. (2000). Retrieved from life.illinois.edu.