Plant cells share a lot of similarities and dissimilarities with animal cells. Some structures are present equally in both plant and animal cells. However, there are some structures which are exclusive only to animal cells or plant cells.
One such structure is flagella. Flagella is the structure in cells that helps with motility and progression in a favorable environment. But do plant cells have flagella? Is there any role of flagella in plant cells?
Let’s find out what flagella is and how it functions in the discussion below.
What are flagella, and What Do they Do?
Flagella are one of the most important attributes in a cell. They can be defined as hair-like or lash-like structures of the cell. They are also known as the ‘organ of locomotion. As their name suggests, flagella assist in locomotion and accumulation of food. They also have an active role in circulation.
Flagella are usually located at the terminal ends or poles of the cells. They may be one in number or maybe several in number, depending on the organism and species.
So, where did the name ‘flagella’ come from?
It originated from the Latin word ‘flagellum,’ which denotes a whip. Since it resembles a whip and is long and slender in appearance, it received the name flagella.
Flagella may be present in certain organisms like bacteria, protozoa, algae, fungi, and some animals. It is usually a notable feature of the Mastigophora group but may be present in a wide range of species.
The main function of flagella is to help in locomotion. In bacterial cells, flagella help in proceeding towards their destination. Flagella also has an active role in motility and fertilization. Spermatic cells contain flagella at the end of their structures which helps them to move towards the ovum and engage in fertilization, which later undergoes implantation. So, flagella are known to have an important role in the progression of zygotes.
Besides, flagella also play role in the colonization of host tissue surfaces, which prepares for invasion. They also take part in the exchange of essential nutrients and waste substances in certain bacteria.
Flagella also has an active role in maintaining the cytoplasmic pH in any cell. This locomotory organ helps in the adaptation of certain organisms to their respective environmental conditions.
Do Plant cells have flagella?
Despite being such an essential organ for locomotion, plant cells lack flagella. Since plant cells do not have to move like bacteria or animal cells, there are no flagella present within them.
However, plant sperm cells bear one or more flagella at the ends of their cells. This is because plant sperm cells have to take part in fertilization and zygote formation. So, even though there are no flagella in plant cells, plant sperm cells are always flagellated.
Flagella is an exclusive structure for eukaryotic cells that consist of membrane-bound organelles. Most bacteria, algae, and fungi are included in this category. Animal cells also bear flagella for the purpose of passage.
How Do Flagella Help Cells Move?
Flagella helps cells move from one position to another with the help of bacterial chemotaxis. This kind of chemotaxis involves the movement of bacteria towards environmental conditions that have the optimum amount of beneficial chemicals and a low amount of toxins.
Flagella assist in cellular movement by conducting a corkscrew motion to impel the cell. Cilia is another hair-like extension of the cell which acts in a similar way to aid in motility and locomotion.
Different Types of Flagella
Flagella in cells are mostly of three types- bacterial, archaeal, and eukaryotic flagella. Let’s have a look at what each type looks like-
This type of flagella is probably the longest type of flagella available. It surpasses the eukaryotic and archaeal flagella in size and consistency. Usually, this type of flagella is very thin and measures about 20 nm in diameter.
They have a helical shape which sets them apart from eukaryotic or archaeal flagella. The basal bodies of the bacteria consist of a rotary motor which has total control over the movement of the bacterial flagella. There are almost 30 proteins in this type of flagella.
On the other hand, archaeal flagella are thinner in consistency and bear hooks that vary from one species to another in terms of length. This type of flagella has exceptional speed and is organized in a right-handed helix.
Eukaryotic flagella are a characteristic structure of eukaryotic cells, mostly the cells containing membrane-bound organelles. Animal cells like sperms, algae, fungi etc., contain eukaryotic flagella.
This type of flagella contains hundreds of proteins in its structure and has to depend on microtubules sliding for locomotion. Their main functions include assisting in fertilization, cell feeding, and progression to a favorable environment.
Bringing it to the end, it can be said that the importance of flagella in locomotion and motility is immense. In bacterial cells and different animal cells, flagella play a very crucial role in helping them adapt to a favorable environment. However, since plants do not require any means for movement, flagella are absent in plant cells.