What do you really know about algae? In this lesson we’ll take a look at red, green, and brown algae, including their characteristics and their importance, both naturally and commercially.
What are Algae?
You’ve likely heard of algae, but how much do you really know about them? People often confuse algae with plants because they look similar and both are autotrophic, or self-feeders, but algae are very special organisms, and they are definitely not plants! While they are all called algae, the organisms that fall into this classification can be quite different from each other, so much so that they are found in multiple different phyla. Algae can be uni- or multicellular, are found in both fresh- and saltwater environments, come in all different shapes and colors, and have both natural and commercial importance.Since there’s no good way to describe all algae, what we’ll do here is just cover a few important ones that you should know about: red algae, green algae, and brown algae.
Ready to get started?
Red algae are named as such because of their bright red color, and there are over 6,000 of species of them. They have chlorophyll, but they’ll also have an accessory pigment that hides the green color that is usually associated with it. Most red algae are multicellular, and many species are important in the building and maintaining of coral reefs. Not surprisingly, most red algae species like to make their home in warm, tropical waters.Red algae are also commercially important. Carrageenan is a gel used to stabilize man-made products, such as ice cream and pudding (yum!), and is derived from some species of red algae. Some of the most common red algae are coralline algae and Irish moss.
Next up are green algae, which can be found as colonies, unicellular organisms, and multicellular seaweeds. As you might expect, these guys get their name from their bright green color. They are found in both fresh and saltwater environments, and some even live on land in very wet soils. Green algae are also quite diverse, with over 4,000 known species on Earth. Some of the most well-known are sea lettuce and dead man’s fingers.Green algae are an important food source for many aquatic animals. They also contain beta carotene, which is used in a number of commercial applications such as food coloring and some cancer prevention treatments.
Last but certainly not least are the brown algae. You are probably most familiar with these, because these are things like kelp and sargassum. There are almost 2,000 species of brown algae, none of which are known to be unicellular. They are the largest of the three algae and are almost exclusively found in marine environments. They also have a root-like structure than anchors them into the ground, which creates environments like the beautiful kelp forests underwater.
Like green algae, brown algae are also an important food source to many marine organisms like otters, fish, and even sea urchins.You’ve probably guessed by now that brown algae are also important to humans, and you’re right! Brown algae have components that can form gels that are used in toothpastes, ice creams, soaps, and so much more! Did you ever think that seaweed could be so exciting and useful?
While the word ‘algae’ sounds simple enough, these organisms are so diverse that there’s no way to describe them all succinctly. Some of the most important algae are the red, green, and brown algae, which even among themselves, differ quite a bit. Some of these algae are found in freshwater environments, but most are marine. The brown algae are the only ones that are not known to be unicellular, and all three are autotrophs, or self-feeders.Red, green, and brown algae are all important components of marine environments. Red algae are involved in the building and support of coral reefs, and green and brown algae provide an important food source for marine life.
All three are commercially important as well, providing natural gels, pigments, and other components to our toiletries, medicines, and so much more.