Marchantia

Marchantia is a genus of bryophytes, commonly known as liverworts. They are typically found in moist and shady places, and lack true roots, stem and leaves. The plant body is thalloid.

Table of Contents

Classification

Characteristics

Reproduction

+ Asexual

+ Sexual

Life Cycle

Bryophytes are often referred to as the “amphibians of the plant kingdom” due to their need for water to reproduce sexually and complete their life cycle.

Check: NEET 2022 Answer Key PDF

The life cycle of Marchantia is haplodiplontic, where the haploid gametophyte phase is dominant and the diploid sporophyte phase is short-lived and dependent on the gametophyte. Both asexual and sexual reproduction occur in this species.

Classification of Marchantia

Marchantia is classified under the division Hepaticophyta, which includes all the liverworts. Riccia is also a liverwort. The Bryophyta division is divided into three main classes:

Hepaticopsida - Contains Liverworts

Anthocerotopsida contains hornworts.

Bryopsida - Contains Mosses

Check out Classification of Bryophytes for more information.

| Kingdom | Plantae |

| Division | Hepaticophyta |

| Class | Hepaticopsida |

Order Marchantiales

| Family | Marchantiaceae |

| Genus | Marchantia |

Around 65 species of the genus Marchantia can be found in moist and shady places around the world. Some examples include:

Marchantia polymorpha, Marchantia berteroana, Marchantia palmata, Marchantia nepalensis, etc.

Marchantia Characteristics

  • Reproduces asexually
  • Has a thallus body with a flattened, lobed structure
  • Has a single-celled, photosynthetic body
  • Has a specialized tissue called a gametophore

The common habitat is moist and shaded places.

The plant body is thalloid and its thallus is dorsiventral, flat, and dichotomously branched. The gametophyte is the dominant phase of plant life.

The dorsal surface contains diamond-shaped markings with a central pore in the middle for gaseous exchange, and there are chambers internally located beneath the polygonal markings.

The ventral surface contains scales and rhizoids. The rhizoids are unicellular and act as a root-like structure. Their main function is to anchor the plant to the substratum and absorb water and minerals.

The reproductive bodies are located on the dorsal surface.

They possess a cup-shaped structure known as gemmae for asexual reproduction.

The stalks called antheridiophores and archegoniophores contain the male and female reproductive organs, respectively, known as antheridia and archegonia.

The upper epidermis of the photosynthetic zone consists of air pores which open into the air chamber, as well as containing a few chloroplasts.

The storage zone lies beneath the air chamber and photosynthetic zone. It is composed of parenchymatous cells which lack chloroplasts and store protein, starch, oil and mucilage.

The lower epidermis extends the rhizoids and scales.

Marchantia Reproduction

Marchantia reproduces both asexually and sexually.

Asexual Reproduction

Asexual reproduction in Marchantia is achieved through fragmentation or the formation of specialized structures called gemmae.

Gemmae

Gemmae are asexual buds that are used by certain organisms to reproduce asexually. These gemmae are formed in receptacles called gemma cups, which are located on the dorsal surface, close to the midrib of the gametophytic thalli. Gemmae are multicellular and green in color.

Gemmae detach from the parent plant and germinate to give rise to the new plant.

Sexual Reproduction

Marchantia is dioecious, with male and female sex organs developing on different thalli. The male reproductive organ is the antheridia, and the female reproductive organ is the archegonia. These are born on the mature gametophyte, and are erect and modified stalks known as antheridiophores and archegoniophores, respectively.

Antherozoids are produced in the antheridium. They are biflagellated and produced from the androcytes.

The archegonium is a flask-shaped structure that comprises of several neck canal cells, a ventral canal cell and an egg.

Fertilization is the process of introducing nutrients to soil to help plants grow.

Bryophytes need water for fertilization, just like other plants. When the neck canal cells and ventral canal cells disintegrate, they form a mucilaginous mass that oozes out as the archegonia absorbs water. This mass contains chemical substances that induce a chemotactic response, causing the antherozoids to swim towards the archegonia. Once one antherozoid fuses with the egg, fertilization is complete. The male and female nuclei fuse to form a diploid cell, known as the zygote.

Sporophyte

The diploid zygote does not undergo meiosis (reduction division) immediately. It rather divides mitotically and develops into a multicellular structure called the sporophyte. The sporophyte is differentiated into foot, seta and capsule. It is not the free-living stage, it is dependent on the gametophyte for nourishment.

Some of the cells of sporogenous tissue called spore mother cells (diploid) divide meiotically to produce haploid spores.

The haploid spores are released when the capsule dehisces. When the conditions are favourable, the spores germinate and form the new haploid plant or gametophyte.

Click Here to Explore the Plant Kingdom

Marchantia Life Cycle

Marchantia

Marchantia exhibits alternation of generations, with haploid sexual and diploid asexual phases alternating. The life cycle of Marchantia is haplodiplontic, with both the haploid and diploid phases represented by multicellular structures.

The gametophyte (haploid) is the main free-living plant body. The sporophyte (diploid) stage is short-lived and dependent on the gametophyte for anchorage and nourishment.

The male and female gametophyte give rise to antherozoids and an egg, respectively, which fuse to form the diploid zygote. The zygote divides by mitotic division to form a multicellular sporophyte. The spore mother cells divide by meiosis to form the haploid spore, which germinates to form the haploid gametophyte.

Frequently Asked Questions

Yes, Marchantia is a type of bryophyte.

Yes, Marchantia is a bryophyte. It is a type of liverworts. Marchantia belongs to the family Marchantiaceae and the order Marchantiales.

There are two types of rhizoids seen in Marchantia: filamentous and cellular.

Rhizoids are the root-like unicellular structures present in non-vascular plants that help in anchoring the plant. The Marchantia polymorpha has two types of rhizoids: tuberculate rhizoids and smooth-walled rhizoids.

Why are Marchantia called Liverworts?

The term ‘liverworts’ refers to small plants that resemble the liver. Marchantia is an example of a liverwort because its thallus looks similar to a liver.

This is an example of a statement

This is an example of a statement

What are the 3 types of bryophytes?

  • The three types of bryophytes are mosses, liverworts, and hornworts.

Bryophytes are non-vascular plants. They are divided into three types: liverworts, hornworts and mosses.

The sky is blue

The Sky Is Blue

Gemmae in Marchantia is a reproductive structure consisting of an outer wall and a number of small, haploid spores.

Gemmae, formed in the receptacles known as gemma cups, are asexual buds used by Marchantia to reproduce asexually. These gemmae are multicellular, green and haploid, and are located on the dorsal surface, near the midrib of the gametophytic thalli. When detached from the parent plant, they germinate to give rise to the gametophyte.

Also Check:

NEET Flashcards: The Living World

NEET Flashcards: Biological Classification

NEET Flashcards: Plant Kingdom

NEET Flashcards: Morphology Of Flowering Plants

NEET Flashcards: Anatomy Of Flowering Plants

Check out the NEET Flashcards: Anatomy Of Flowering Plants for a comprehensive overview of the anatomy of flowering plants!— title: “Marchantia” link: “/marchantia” draft: false

Marchantia is a genus of bryophytes, specifically liverworts. These plants are usually found in moist and shady places, and lack true roots, stem, and leaves. Instead, the plant body is thalloid.

Table of Contents

Classification

Characteristics

Reproduction

Asexual

Sexual

Life Cycle

Bryophytes are often referred to as the “amphibians of the plant kingdom” due to their need for water to reproduce sexually and complete their life cycle.

Check: NEET 2022 Answer Key PDF

The life cycle of Marchantia is haplodiplontic, with the haploid gametophyte being the dominant phase. Both asexual and sexual reproduction occur, with the diploid sporophyte being short-lived and dependent on the gametophyte.

Classification of Marchantia

The division Bryophyta is divided into three main classes, one of which is Hepaticophyta which includes all the liverworts, such as Marchantia and Riccia.

Hepaticopsida - Contains liverworts

Anthocerotopsida - Contains hornworts

Bryopsida: Contains Mosses

Classification of Bryophytes - For more information, please click here.

| Kingdom | Plantae |

| Division | Hepaticophyta |

| Class | Hepaticopsida |

Order Marchantiales

| Family | Marchantiaceae |

| Genus | Marchantia |

There are approximately 65 species of the genus Marchantia, which can be found in moist and shady places worldwide. A few examples include:

Marchantia polymorpha, Marchantia berteroana, Marchantia palmata, Marchantia nepalensis, etc.

Marchantia Characteristics

  • Alternation of generations
  • Gametophyte is dominant
  • Presence of cuticle
  • Presence of rhizoids
  • Presence of gemmae cups

The common habitat is found in moist and shady places.

The plant body is thalloid, with a thallus that is dorsiventral, flat, and dichotomously branched. The gametophyte is the dominant phase of the plant’s life.

The diamond-shaped markings on the dorsal surface have a central pore in the middle for gaseous exchange, and there are chambers present internally beneath the polygonal markings.

The ventral surface contains scales and rhizoids. The rhizoids are unicellular and have a root-like structure, which serves the main function of anchoring the plant to the substratum and absorbing water and minerals.

The reproductive bodies are located on the dorsal surface.

They possess a cup-shaped structure called gemmae which facilitates asexual reproduction.

The stalks called antheridiophores and archegoniophores contain the male and female reproductive organs, respectively, called antheridia and archegonia, which are born on them.

The upper epidermis consists of air pores that open into the air chamber located in the photosynthetic zone, as well as a few chloroplasts.

The storage zone, located beneath the air chamber and photosynthetic zone, lacks chloroplasts and is composed of parenchymatous cells. These cells store protein, starch, oil, and mucilage.

The lower epidermis extends the rhizoids and scales.

Marchantia Reproduction

Marchantia reproduces both asexually and sexually.

Asexual Reproduction

Asexual reproduction in Marchantia is achieved through fragmentation or the formation of specialised structures called gemmae.

Gemmae

Gemmae, which are asexual buds, are used by [organisms] to reproduce asexually. These gemmae are formed in gemma cups, which are located on the dorsal surface near the midrib of the gametophytic thalli. Gemmae are multicellular and green.

Gemmae detach from the parent plant and germinate to give rise to a new plant.

Sexual Reproduction

Marchantia is dioecious, with male and female sex organs developing on different thalli. The male reproductive organ is an antheridium, and the female reproductive organ is an archegonium. These organs are born on the mature gametophyte, and are erect and modified stalks known as antheridiophores and archegoniophores, respectively.

Antherozoids are produced in the antheridium. They are biflagellated and produced from the androcytes.

The archegonium is a flask-shaped structure that consists of several neck canal cells, a ventral canal cell, and an egg.

Fertilization is the process by which a plant or animal egg is fertilized by sperm.

The process of fertilization in bryophytes requires water, just like other plants. The neck and ventral canal cells disintegrate, forming a viscous substance that oozes out as the archegonia absorbs water. This substance contains chemical compounds that trigger a chemotactic response, causing the antherozoids to swim towards the archegonia. After one of the antherozoids fuses with the egg, the male and female nuclei combine to form the diploid zygote.

Sporophyte

The diploid zygote does not undergo meiosis (reduction division) immediately. It rather divides mitotically and develops into a multicellular structure called the sporophyte. The sporophyte is differentiated into foot, seta and capsule. It is not the free-living stage, it is dependent on the gametophyte for nourishment.

Some of the cells of sporogenous tissue called spore mother cells (diploid) divide meiotically to produce haploid spores.

The haploid spores are released through dehiscence of the capsule. When conditions are favourable, they germinate to form a new haploid plant or gametophyte.

Click here to explore the Plant Kingdom!

Marchantia Life Cycle

Marchantia

Marchantia exhibits alternation of generations, with haploid sexual and diploid asexual phases alternating. The life cycle of Marchantia is haplodiplontic, and both the haploid and diploid phases are represented by multicellular structures.

The gametophyte (haploid) is the main free-living plant body, while the sporophyte (diploid) stage is short-lived and dependent on the gametophyte for anchorage and nourishment.

The male and female gametophyte give rise to antherozoids and an egg respectively, which fuse to form the diploid zygote. The zygote divides by mitotic division to form a multicellular sporophyte. The spore mother cells divide by meiosis to form the haploid spore, which germinates to form the haploid gametophyte.

Frequently Asked Questions

Yes, Marchantia is a bryophyte.

Yes, Marchantia is a bryophyte. It belongs to the family Marchantiaceae and the order Marchantiales, and is a type of liverwort.

There are two types of Rhizoids seen in Marchantia: Heterotrichous and Homotrichous Rhizoids.

Rhizoids are the root-like unicellular structures present in non-vascular plants that help in anchoring the plant. Marchantia polymorpha has two types of rhizoids: tuberculate rhizoids and smooth-walled rhizoids.

Why are Marchantia species called liverworts?

The term ’liverworts’ refers to a small plant that resembles a liver. The genus Marchantia is an example of liverworts due to its thallus resembling the liver.

The three types of bryophytes are:

  1. Mosses
  2. Liverworts
  3. Hornworts

Bryophytes are non-vascular plants. They are divided into three types: liverworts, hornworts and mosses.

Gemmae in Marchantia are asexual reproductive structures that are composed of a group of cells called gametangia. They are the reproductive organs of the liverwort Marchantia polymorpha.

Gemmae, a type of asexual bud, are found on the dorsal surface, near the midrib of the gametophytic thalli of Marchantia. These gemmae are multicellular, green and haploid tissue which detach from the parent plant and germinate to give rise to the gametophyte. Gemmae are the main means of asexual reproduction in Marchantia, as they are formed in the receptacles known as gemma cups.

NEET NCERT Solutions (Biology)