Thallophyta: Definition, Features & Examples

Thallophyte, also known as thallobionta or thallophyta, are non – mobile organisms of a polyphyletic group that are conventionally called “lower plants” or “relatively small plants” or “thalloid plants”. The plant has a hidden system of reproduction and as a result, they are included in Cryptogamae. But as opposed to the cormophytes, the Thallophyte has undifferentiated bodies with stems and roots. In the marine ecosystem, different kinds or groups of Thallophytes contribute to a large extent to their entire sphere and dynamism. The most popular definition of thellaphyte given in the Merriam – webster ( one of the most trusted online dictionaries) states, “it is any of a group of plants or plantlike organisms (such as algae and fungi) that lack differentiated stems, leaves, and roots and that was formerly classified as a primary division (Thallophyta) of the plant kingdom”. It is comprised of lichens, fungi and algae. The plant body has the absence of a vascular system which means that there is no availability of the conducting tissues.

Characteristics of Thallophyta

• Some of the basic characteristics of thallophyta are mentioned below:

• Their sex organs are single-celled and simple.

• There is the provision of forming an embryo once the fertilisation is done or over.

• It is not like the other plants in the context that there is no presence of phloem or xylem found.

• Vascular tissue is not present in the plant.

• Around their cells, they have a cellulose composing cell wall.

• One of the different and unique characteristics of the thallophyta is that there is the production of glucose after photosynthesis and a part of this is consumed immediately. The remaining part of glucose is transformed into starch, a kind of complex compound.

• The food that is reserved by the plant generally appears to be starch.

• Most of the members of the group are responsible for manufacturing their food. However, a few of them, for instance: fungi are dependent for their food on other sources.

• Their nature is found to be autotrophic.

• These groups of members are mostly found in wet or moist places.

• It happens because of the absence of vascular tissue and “true roots” which is required to make a network of connections for minerals and water. Because of this, they are found in wet and moist places.

• The members of this group are one of the most primitive forms of plants. Their body is not found to be differentiated between leaves, stem and roots. They appear to be in the form of an undistinguished thallus. The group is commonly termed algae.

• Their sexual reproduction takes place by the amalgamation of two gametes.

• There may or may not be any alteration of generation present or available. Their life cycle may be divided into diplohaplontic, diplontic or diploid.

• The body of the plants is segregated into different parts like leaves, stem or root.

Division of Thallophyta

If we ever have a look into the broader aspect or Division of the plant kingdom, Thallophyta comes at the lowermost part. It does not possess a well–structured design of the body. It means that there is no structure of the plant body as others in the form of roots, stems or leaves. These plants are permanently aquatic and commonly termed algae. However, in addition to the above-mentioned segmentation of the plant kingdom, there is also a sub-division of this specific plant is available. Thallophyta is classified into two broad Divisions; these are fungi and algae.

Fungi:

These are the achlorophyllous (as they are not able to produce chlorophyll) heterotrophic Thallophytes. To overcome the handicap, there is the probability that very often the fungi may generate a symbiotic connection with a cyanobacterium or an alga. Since the algae contain chlorophyll, they can produce the food by themselves and in return, the fungi shield the algae by providing it with a safe environment and keeping it safe from the UV rays. One of the important examples is lichen where two organisms are found to be acting in the form of a single unit. Some of the characteristics of fungi are:

• They are non – motile.

• They can be considered as the best recycler.

• Unlike a plant, instead of cellulose, chitin is used to make up the cell walls.

Algae:

These are the thalloid bearing chlorophyll. They are mostly aquatic plants and are autotrophic. In addition to this, it is also observed that green algae are found to be forming a symbiotic network of connection with sloths. It is to be mentioned here that sloths are native to Central America and South America’s lush tropical rainforests. It is because of this that the algae are given chance to flourish because the sloth fur creates a damp and moist environment for them. In return for this, the alga gives the sloth safety from the predators by giving it a chance of camouflage and also providing it extra nutrition. Spirogyra is one of the most common and important examples of this. Some of the basic characteristics of algae are:

• These do not have any leaves, stems or roots.

• To carry out the process of photosynthesis, they have chlorophyll as well as other forms of pigment.

• They can be both unicellular and multicellular.

• Most of the time in water that the unicellular algae are occurred, specifically in plankton.

In Summary

• Thallophytes is non – mobile organisms of the polyphyletic group.

• They are conventionally called “lower plants” or “relatively small plants” or “thalloid plants”.

• Their life cycle may be divided into diplohaplontic, diplontic or diploid.

• Spirogyra is one of the most common and important examples of this.

• Thallophyta is classified into two broad divisions; these are fungi and algae.

Thallophyta, it is Characteristics and Examples

A set organism or any other evolving elements, which are grouped according to its characteristics but does not necessarily mean that they share a common ancestor is termed as the Polyphyletic group, and the Polyphyletic non-motile organisms, which are normally described as “Thalloid Plants”, or “lower plants”, or even “Relatively simple plants” are called Thallophytes.

Thallophyte creates a separation of the Plantae Kingdom which remains isolated from the others and includes lichens and algae, and rarely bryophytes, bacteria, and slime moulds. Thallophytes are incorporated into the similar abandoned Crytptogamae as opposed to the Phanerogamae because Thallophytes have a hidden reproductive system. In the ecosystems of the marine Various groups of thallophytes are the major contributors.

Characteristics of Thallophyta

Major characteristics of Thallophyta are given below:

• For the most part, Thallophytes are found in moist or wet places.

• The reserve food of the Thallophyta is generally starch.

• The vascular tissue which is xylem and phloem are not found in the Thallophyte, because they are aquatic habitats, and hence the water conduction is not required for it.

• The vegetative reproduction of the Thallophyta is by the fragmentation, as Each of the Fragments develops into a thallus.

• The reproductive organs of the Thallophyta are single-celled and there is no embryo formation in Thallophyta after the fertilisation. Also, cellulose is found in their cell walls.

• Thallophyte consumes the glucose almost immediately after the production of the same through photosynthesis. And this is one of the unique characteristics of the Thallophyte.