What is prothallus Class 11?

Prothallus refers to gametophytes of bog moss or liverwort. It is a fungus that develops from germinated spores. They are heart-shaped structures and are short-lived. Their structure and appearance differ according to the species.

Why is it called prothallus?

A prothallus, or prothallium, (from Latin pro = forwards and Greek θαλλος (thallos) = twig) is usually the gametophyte stage in the life of a fern or other pteridophyte. Occasionally the term is also used to describe the young gametophyte of a liverwort or peat moss as well.

What is thallus and prothallus?

A prothallus is the haploid gametophyte stage of a fern or other seedless vascular plant. A thallus is the vegetative body of a green alga or other photosynthetic protist. A prothallus is a haploid structure that is the sexual reproductive organ of a fern.

What is prothallus cell?

prothallium, the small, green, heart-shaped structure (gametophyte) of a fern that produces both male and female sex cells (gametes). The prothallium forms from a spore.

What is the Colour of prothallus?

Prothallus is the gametophyte of pteridophytes. Gametophyte in pteridophytes is independent, bears sex organs and is green in colour due to the presence of chlorophyll pigments.

Is prothallus haploid or diploid?

It has haploid spores in it both male and female due to which it is known to be monoecious when it has independent male or female spores it is known to be diecious prothallus. Correct option is C.) A gametophyte free-living structure formed in pteridophytes.

What is prothallus describe its structure?

The prothallial cell divides to form the filament-like structure which has an apical cell. The apical cell divides and forms a structure of small prothallus. The cells mature and result in the formation of a prothallus which is flat and dorsiventral in shape.

What is prothallus topper?

Hence, A prothallus is a gametophytic-free living structure formed in pteridophytes. Solve any question of Plant Kingdom with:- Patterns of problems.

What is prothallus Ncert?

The prothallus is the fern gametophyte. It is a green, photosynthetic structure that is one cell thick, usually heart or kidney-shaped, 3–10 mm long and 2–8 mm broad. It doesn’t have roots, stems or leaves, but it does have rhizoids that anchor it to the soil and help with absorption.

What is prothallus and protonema?

The protonema and prothallus are structures seen in primitive plants. The key difference between both these structures is that protonema constitutes the first stage of development in liverworts and mosses, while prothallus is seen in pteridophytes and is its gametophyte.

Is prothallus monoecious or dioecious?

Thus, the heart shaped form of prothallus in homosporous species of pteridophytes represents monoecious gametophyte stage.

What does prothallus fern produce?

Prothallus of fern produces male and female gametes which after fertilization give rise to dioploid sporophyte which produces spores. The underside of the prothallus is where the gametes are produced from the male and female sex organs. The prothallus has both male and female sex organs.

What is ploidy class 11?

Ploidy is the number of sets of chromosomes in a cell or organism. Types of ploidy: Haploid: Haploid means the presence of a single set of chromosomes in an organism. Diploid: Diploid means the presence of two sets of chromosomes in an organism.

Is prothallus found in Cycas?

Answer: Prothallus is not found in – O Cycas. Explanation: Cycas is a Gymnosperm.

Why prothallus is known as the gametophyte of pteridophytes?

Prothallus is autotrophic, independent and free-living in nature. The male and female sex organs can develop either on a single prothallus (monoecious) or on a different prothallus (dioecious). Hence, a prothallus is a gametophyte and free-living structure formed in pteridophytes.

What is dioecious prothallus?

The prothallus is monoecious (ferns) or dioecious (Selaginella). It bears sex organs i.e., male antheridia and female archegonia. They are present ventrally. Prothallus is autotrophic. So, the correct answer is option A and C ‘Gametophyte, monoecious or dioecious and autotrophic present in pteridophyte.

Where is the prothallus of a fern?

Definition. The structure representing that part of a fern’s life cycle between the germination of the haploid spore and the formation of the zygote. Fern prothalli are small, green, often heart-shaped, and bear the archegonia and antheridia where the egg and sperm are produced, respectively.

Where is archegonia found?

archegonium, the female reproductive organ in ferns and mosses. An archegonium also occurs in some gymnosperms, e.g., cycads and conifers. A flask-shaped structure, it consists of a neck, with one or more layers of cells, and a swollen base—the venter—which contains the egg.

Is archegonia haploid or diploid?

Is the archegonium diploid or haploid? The archegonium is a haploid structure.

Is prothallus a haploid structure?

A gametophyte is the plant that produces gametes. The fern gametophyte is a small (approximately 5 mm), bisexual, heart-shaped plant called a prothallus. The prothallus is haploid, since it grew from a spore which had been formed by meiosis.

How are pteridophytes prothallus formed?

(c) Prothallus is usually a gametophyte stage in the life of a Pteridophyte. Spore germinates to form a prothalium, it is short lived inconspicuous heart shaped structure with a number of rhizoids developed beneath and sex organs, archegonium and antheridium.

Is prothallus the same as gametophyte?

Gametophytes contain both female (archegonium) and male (antheridium) sex organs. They mature at different times in order to increase the chances of cross-fertilisation and genetic variation. The prothallus is the fern gametophyte.

Is prothallus photosynthetic?

Prothallus of pteridophytes is inconspicuous small, multicellular, free living photosynthetic thalloid gametophyte. Haploid spore germinats to form a flat green heart shaped prothallus. It is monoecious, i.e., both sex organ male (antheridia) and female (archegonia) are present.

What is rhizoids in biology?

rhizoid, a short, thin filament found in fungi and in certain plants and sponges that anchors the growing (vegetative) body of the organism to a substratum and that is capable of absorbing nutrients. In fungi, the rhizoid is found in the thallus and resembles a root.

What is Protonema Class 11?

Hint: Protonema is a creeping, green, branched, and often filamentous stage of the growth process. It is a haploid, autonomous, gametophytic stage of the moss life cycle. Complete answer: A protonema is a thread-like chain of cells that forms the gametophyte’s earliest stage of growth in the life cycle of mosses.

Do NOT follow this link or you will be banned from the site!