Phanerogams: Definition, Characteristics & Importance

In 1883 a German botanist A.W Eichler divided the whole plant kingdom into Phanerogams and Cryptogams. Phanerogams are the most advanced plants on our planet, and their plant body is divided into roots, stems, and leaves. They have particular reproductive organs that produce seeds, also known as seed-producing plants. 

The pine trees, grasses, crops, flowers, bamboo trees, etc., which we see around us all belong to Phanerogams. It is the largest subkingdom, divided into two parts: gymnosperm and angiosperm. Let us go through this article to learn more about the main aspects of Phanerogams.

Phanerogams Definition 

“Plants with well-differentiated reproductive parts that ultimately make seeds are called Phanerogams”. (Source: NCERT) 
Phanerogams are seed-producing plants, and they are the most advanced plant group of the plant kingdom. Phanerogams are formed by two Greek words, “Phaneros”, which means visible and “Gamos”, which means marriage. Phanerogams are also known as Spermatophytes

Characteristics of Phanerogams

The characteristics of Phanerogams are given below:

1. These plants are always multicellular and eukaryotic. The plant body is divided into distinct roots, shoots, and leaves. 
2. The major phase is represented by diploid and sporophytic. They are commonly called flowering plants.
3. They produce special reproductive structures and generate seeds. Seeds enclose the future generation. They are also called Spermatophyta.
4. The majority of these are chlorophyllous and are autotrophic. Certain plants are parasitic (like Cuscuta, Viscum) or achlorophyllous (like Cuscuta).
5. They contain conducting elements, like xylem and phloem. The xylem may be without vessels (as in most Gymnosperms) or vessels (as in Angiosperms). So they are also called Tracheophyta.
6. The phloem may be without companion cells (as in most Gymnosperms) or companion cells (as in most Angiosperms).
7. They occupy worldwide distribution. Gymnosperms are restricted to colder climatic regions, but the Angiosperms are present in all possible climatic conditions. They also occupy terrestrial and aquatic habitats.
8. The reproduction is sexual and vegetative. Asexual spores are absent in them. Flowers (or cones or strobili) are reproductive structures.
9. They show alternation of generation. The lifecycle of these plants is completed in two generations: sporophytic generation and gametophytic generation.
10. The gametophytic generation is much reduced and is represented by cells. They have no independent existence.
11. Flagellates male gametes are absent, except for primitive Gymnosperms (Cycas has multiciliate male gametes). Union of gametes is brought about by a technique called siphonogamy.
12. Sexual reproduction is always an oogamous type.

Now you know how to write the characteristics of phanerogams, you can easily understand what phanerogams are.

Classification

The Phanerogams are classified into two parts such as:

1. Gymnosperms (naked seed plants)
2. Angiosperms (covered seed plants)

1. Gymnosperms

Gymnosperms are naked seeded plants. They are also known as primitive seed plants. The word gymnosperm is formed by two Greek words, “Gymno”, which means naked and “Sperma”, which means seed. The features of gymnosperms are:

1. They have restricted distribution in the colder regions of the world.
2. Tall, woody, perennial trees mainly represent them. Few forms are woody climbers. Herbs are absent.
3. Many of them show xerophytic adaptations.
4. Xylem lack vessels (except in a few genera, like Gnetum).
5. They are always heterosporous, producing two spores, microspores (male) and megaspores (female).
6. Microspores are found inside microsporangia on microsporophyll, while megaspores are found inside megasporangia on megasporophyll.
7. Showy flowers are absent. Instead, cones (strobilus) are formed.
8. Ovules are naked; ovaries are absent. Seeds, thus formed, are without fruit walls. 
9. The endosperms are either haploid.

2. Angiosperms

Angiosperms are also known as flowering plants, and they have seeds enclosed within the fruits. The word angiosperm originated from “Angion”, which means hidden, and “Sperma”, which means seed. The features of angiosperms are:

1. They are found in all types of habits and habitats. They are practically adapted to various environmental conditions, like high mountains, desert, water, land, etc.
2. They are found in various forms, like herb, shrub, tree, creeper, twinner, climber, epiphyte, etc.
3. Flowers are the most beautiful part of these angiosperms, and they add beauty to these plants. 
4. They possess vessels in the xylem and companion cells in the phloem (except for some families like Winteraceae).
5. Flowers are the reproductive organ of angiosperms. They are highly reduced and modified shoots for sexual reproduction.
6. They produce fruits (fertilized ovaries). The seeds are enclosed inside the fruits.
7. They are adapted to pollinate abiotic (like wind and water) and various biotic agents (like bees, birds, snails, bats, etc.).
8. They show double fertilization and triple fusion.
9. The endosperm is the product of double fertilization and is triploid. This provides nutrition to the developing embryo.

Phanerogams Examples

The examples of Phenograms are mentioned below:

Gymnosperms

1. Cycas
2. Pinus
3. Ginkgo
4. Gnetum
5. Ephedra

Angiosperms

1. Sunflower 
2. Rose
3. Mustards
4. Bamboo
5. Wheat

                        Fig: Examples of Phanerogams

Importance of Phanerogams

The importance of Phanerogams is mentioned below:

1. They are the source of food for humans and other living organisms, and they also provide habitat to animals.
2. These plants prevent soil erosion.
3. They produce oxygen for us to breathe, and thus keeping balance in our ecosystem.
4. These plants are the primary source of paper pulp, lumber, turpentine, resins, cotton, and rubber.
5. They are a good source of fuel.
6. All the timber and hardwood used in the construction of buildings and furniture comes from trees.
7. Some of these plants are also used for decoration and ornaments.

Difference between Cryptogams and Phanerogams

The differences between Cryptogams and Phanerogams are mentioned below:

Summary

Phanerogams is mainly a subkingdom of the plant kingdom. It is classified into two parts: Gymnosperms and Angiosperms. Phanerogams are considered the most advanced group. They are the most primitive plant group on this planet. They are seed-bearing plants and have a unique structure for reproduction.

Moreover, the plant body consists of roots, stem, and leaf. Phanerogams produce their food with the help of photosynthesis, and they also possess chlorophyll. They have a well-developed vascular system. These plants are terrestrial and can be found in habitats like deserts, mountains, and rainforests. You understood about what are the characteristics of phanerogams.

FAQs

Q.1: What are the two main groups of Phanerogams?
Ans: The two main groups of Phanerogams are Gymnosperms and Angiosperms.

Q.2: Which plant group is called Phanerogams without ovaries?
Ans: Gymnosperms are a part of Phanerogams which do not possess ovaries. Gymnosperms are seed-producing plants with unclosed seeds, i.e., their seeds are open without any protection. Gymnosperms have naked seeds, which results in the lack of an ovary as the seeds are not contained in fruit.

Q.3: What are Phanerogams in biology?
Ans: Phanerogams possess special structures for reproduction and generate seeds. In these plants, the seed is formed after reproduction. The seed contains an embryo and stores food that is used for the initial growth of the embryo at the time of germination of seed.

Q.4: Which plants are called Phanerogams?
Ans: The plants which produce seeds are called Phanerogams.

We hope you find the Phanerogams information helpful. In case of any queries, you can reach back to us in the comments section, and we will try to solve them.