Bryophytes (General) Questions in English

(B) The capsule wall is a part of the sporophyte generation in mosses,which is $2n$ (diploid).
Since the protonema is developed directly from the cells of the capsule wall through vegetative propagation (apospory),the resulting protonema will retain the same ploidy level as the parent tissue.
Therefore,the protonema will be diploid $(2n)$.

(C) The life cycle of mosses,such as $Funaria$,includes a distinct stage known as the $Protonema$.
$Protonema$ is a creeping,green,branched,and frequently filamentous stage that develops directly from a germinating spore.
It represents the juvenile gametophyte phase in the life cycle of bryophytes,specifically mosses.
$Spirogyra$ is an alga,$Rhizopus$ is a fungus,and $Escherichia$ is a bacterium; none of these organisms possess a $Protonema$ stage.

(D) In $Funaria$,the young sporogonium is covered by a structure called the calyptra.
It is a haploid covering that is derived from the cells of the venter of the archegonium.

(D) The sporophyte of the moss $(Funaria)$ is not differentiated into true roots,stems,or leaves. Instead,it is differentiated into three distinct parts: the foot,the seta,and the capsule. Therefore,the correct option is $(d)$.

(C) In mosses,the capsule is the structure responsible for spore production. The dehiscence (opening) of the capsule to release spores occurs at a specific region known as the $Annulus$. The $Annulus$ is a ring of specialized cells located between the $Operculum$ (lid) and the $Theca$ (main body of the capsule). When these cells dry out and rupture,the $Operculum$ is shed,allowing the spores to be dispersed through the $Peristome$ teeth.

(D) The archegonium of $Funaria$ (a moss) consists of a venter and a long neck.
The neck is composed of six vertical rows of cells.
It contains $6$ or more elongated,uninucleate neck canal cells that degenerate at maturity to form a passage for the male gamete (antherozoid) to reach the egg cell.
Therefore,the correct range is $6$ to $18$.

(B) The $Funaria$ gametophyte is monoecious and autoecious.
$Monoecious$ means that both male (antheridia) and female (archegonia) sex organs are borne on the same plant body.
$Autoecious$ refers to the condition where the male and female sex organs are present on the same individual plant,specifically on different branches of the same gametophyte.

(D) The sporophyte of $Funaria$ consists of three parts: $Foot$,$Seta$,and $Capsule$.
$1$. The $Foot$ is the basal part that anchors the sporophyte to the gametophyte and absorbs nutrients from it.
$2$. The $Seta$ is the stalk that elevates the capsule to facilitate spore dispersal.
$3$. The $Capsule$ contains the $Peristome$ teeth and the $Annulus$,which are specialized structures that regulate the release of spores.
Therefore,the $Foot$ is not involved in spore dispersal,as its primary function is anchorage and absorption.

(A) In $Funaria$,the fully developed sporophyte is differentiated into three distinct regions: the basal foot,the seta,and the capsule.
$1$. The foot is embedded in the gametophyte and absorbs nutrients.
$2$. The seta is the stalk that elevates the capsule.
$3$. The capsule is the terminal part where spores are produced via meiosis.

(B) In mosses,the central part of the stem axis is known as the medulla or central strand. This region consists of a conducting strand made of slightly thick-walled,elongated,dead parenchymatous cells,which is specifically referred to as the $Hadrome$. The $Hadrome$ functions in the conduction of water and minerals,analogous to the xylem in higher plants.

(D) In $Funaria$, vegetative reproduction occurs through several methods.
$1$. $Secondary$ $protonema$: This is the most common method where the protonema develops from the spores or from injured parts of the gametophyte.
$2$. $Primary$ $protonema$: It can also give rise to new gametophores.
$3$. $Gemmae$: These are specialized multicellular buds that detach and grow into new plants.
Since all these structures contribute to vegetative propagation in $Funaria$, the correct answer is $D$.

(B) The dominant phase in the life cycle of $Funaria$ (a moss) is the $Leafy \, gametophyte$.
It develops from the secondary protonema as a lateral bud.
The leafy stage consists of an upright, slender axis bearing spirally arranged leaves.
This stage bears the sex organs (antheridia and archegonia) and is responsible for sexual reproduction.

(C) The $Apophysis$ is the basal sterile portion of the moss capsule that is in direct continuation with the $Seta$. In the capsule of $Funaria$,stomata are present exclusively in the $Apophysis$ region.

(B) The peristome of $Funaria$ consists of a total of $32$ teeth arranged in $2$ concentric rings,with $16$ teeth in each ring.
These are divided into an outer ring of $16$ thick,larger teeth and an inner ring of $16$ thinner,smaller teeth.
The primary function of these peristome teeth is to facilitate the gradual dispersal of spores from the sporangium of the $Funaria$ capsule.

(D) The protonema of moss is a creeping,green,branched,and frequently filamentous stage in the life cycle of mosses. While it resembles green algae in appearance,it is distinct because it possesses:
$1$. Buds: These develop into the leafy gametophore.
$2$. Colourless rhizoids: These help in anchorage and absorption.
$3$. Oblique septa: The cross-walls in the filaments are characteristically oblique.
Therefore,all the mentioned features are characteristic of moss protonema and distinguish it from green algae.

(D) In $Funaria$,the male reproductive organ is the antheridium.
These antheridia are surrounded by sterile,green,multicellular,hair-like filaments known as paraphyses.
These structures help in the protection of the developing antheridia and also assist in the retention of water,which is essential for the dehiscence of antheridia and the movement of antherozoids.

(C) The moss life cycle consists of two phases: the gametophyte and the sporophyte.
$A$. Spores are the first stage of the gametophyte generation.
$B$. The protonema is the juvenile stage of the moss gametophyte.
$C$. The columella is a sterile central column of tissue found within the capsule of the moss sporophyte,not the gametophyte.
$D$. Paraphyses are sterile multicellular hairs found among the sex organs on the gametophyte.
Therefore,the correct answer is $C$.

(A) In mosses,the life cycle is dominated by the haploid gametophyte $(n)$.
However,the sporophyte $(2n)$ is partially or fully dependent on the gametophyte.
The capsule is a part of the sporophyte generation,which is diploid $(2n)$.
Conversely,the gametophyte,archegonia,egg,antheridia,sperm,and spores are all haploid $(n)$ structures.

(D) The moss capsule is a complex structure involved in spore dispersal.
It typically contains a central sterile region called the columella,a specialized ring of teeth-like structures called the peristome,and air spaces bridged by filaments known as trabeculae.
Prostomium is a structure found in annelids (earthworms),not in mosses.
Therefore,the correct answer is $D$.

(C) In $Funaria$,the female sex organ is known as the $archegonium$.
These $archegonia$ are produced at the apex of the female branch,which is typically larger than the male shoot.

(B) The stem of $Funaria$ is densely covered with simple,sessile,and ovate leaves. These leaves are arranged in a spiral manner around the stem axis.

(B) The capsule of $Funaria$ is considered a semi-parasite because it remains attached to the gametophyte through the foot and seta.
It absorbs water and minerals from the gametophyte,but it contains chlorophyll and is capable of synthesizing its own food through photosynthesis.

(B) $Funaria$ belongs to the group $Bryophyta$. The defining characteristics of bryophytes include the absence of true roots,stems,and leaves (they have root-like,stem-like,and leaf-like structures). They are non-vascular plants,meaning they lack specialized xylem and phloem tissues. $A$ key feature of their life cycle is that the sporophyte is multicellular and permanently attached to the photosynthetic gametophyte for nutrition. Therefore,option $B$ is the correct description of a bryophyte characteristic among the choices provided.

(C) In mosses (Bryophytes),the life cycle is haplodiplontic.
The gametophyte is the dominant,independent,and photosynthetic phase.
The sporophyte is multicellular and is not free-living; instead,it remains attached to the photosynthetic gametophyte and derives nourishment from it.
Therefore,the gametophyte is independent,and the sporophyte is dependent on the gametophyte for nutrition.

(C) In $Funaria$,the spores germinate to produce a branched,filamentous,green,creeping structure known as the $Protonema$. This $Protonema$ stage represents the juvenile phase of the gametophyte in mosses,which later develops into the leafy gametophore.

(B) $Funaria$ is a moss belonging to the class $Bryopsida$. In the sporophyte of $Funaria$,the capsule is differentiated into three parts: $apophysis$,$theca$,and $operculum$. The $apophysis$ is the basal sterile part of the capsule. The epidermis of the $apophysis$ contains stomata,which facilitate gaseous exchange for the developing sporophyte.

(B) Mosses lack true vascular tissues like xylem and phloem.
Instead,the axis of a moss plant contains a central conducting strand composed of slightly thick-walled,elongated parenchymatous cells.
This specialized tissue is known as 'hadrom' and is responsible for the conduction of water.

(A) The apophysis is the sterile basal part of the capsule in mosses (like Funaria).
All cells in the apophysis region contain chloroplasts and are chlorophyllous,which allows them to perform photosynthesis to provide nutrition to the developing sporophyte.

(C) In the life cycle of mosses like $Funaria$,the spore germinates to produce a creeping,green,branched,and frequently filamentous stage known as the protonema.
This stage represents the juvenile gametophyte.
It eventually develops into the leafy gametophyte stage.

(A) In $Funaria$,the leaves that surround the cluster of archegonia are known as perichaetial leaves.
These leaves form a protective,cup-like structure known as the perichaetium,which encloses the female reproductive organs.

(D) The peristome in $Funaria$ is differentiated into two whorls of radially arranged peristomial teeth. Each whorl consists of $16$ teeth.
The outer ring of these teeth is hygroscopic in nature,meaning they respond to changes in humidity by bending or twisting,which facilitates the gradual dispersal of spores from the capsule.

(B) The spore in $Funaria$ is spherical and possesses two distinct wall layers.
The outer layer is smooth,coloured,and is known as the $exosporium$.
The inner layer is colourless,smooth,and is known as the $endosporium$.
Therefore,the correct answer is $B$.

(B) Mosses exhibit a heteromorphic alternation of generations.
In the life cycle of mosses (like $Funaria$), there are two distinct phases: the gametophytic generation $(haploid)$ and the sporophytic generation $(diploid)$.
The gametophyte is the dominant, independent, and complex phase, while the sporophyte is partially dependent on the gametophyte for nutrition and support.
Since these two generations are morphologically and structurally different, this pattern is termed as heteromorphic alternation of generations.

(C) The main plant body of $Funaria$ is a gametophyte.
It is differentiated into a stem-like axis,leaf-like structures,and multicellular,branched rhizoids.
Therefore,the correct option is $C$.

(B) In $Funaria$,the male sex organ is a reddish-brown,stalked,multicellular structure known as the antheridium,which is club-shaped.

(D) In mosses (Bryophytes),the stem-like axis is structurally simple.
It lacks true vascular tissues like $Xylem$ and $Phloem$.
Instead,the central part of the axis consists of a strand of elongated,thin-walled cells known as the hydrome or conducting tissue,which helps in the conduction of water and nutrients.
Therefore,the centre is occupied by conducting tissue.

(C) In the capsule of the moss $Funaria$,the columella is a central sterile column of cells.
Its primary function is to provide water and essential nutrients to the developing spores within the spore sac.
Therefore,it acts as a nutritive tissue.

(C) The mature sporophyte of $Funaria$ is diploid $(2n)$ in nature.
Spore mother cells are part of the sporophytic generation and are formed within the capsule.
Therefore,these cells are diploid $(2n)$ and undergo meiosis to produce haploid spores.

(C) The calyptra is a protective,haploid covering that surrounds the young sporogonium (sporophyte) in bryophytes.
It is derived from the cells of the venter of the archegonium.
Therefore,it is associated with the sporophyte generation.

(D) In $Funaria$,the zygote undergoes division to form an embryo. The development is described as $Holoblastic$ because the entire zygote is involved in the formation of the embryo. In $Holoblastic$ cleavage,the entire egg or zygote divides completely,which is characteristic of bryophytes like $Funaria$.

(B) The spore is the first cell of the gametophytic generation in $Funaria$.
Upon germination,the spore develops into a filamentous structure known as the $Protonema$.
The $Protonema$ stage is the juvenile phase of the gametophyte,which later gives rise to the leafy gametophore.
Therefore,the development of the $Funaria$ gametophyte is initiated from the $Protonema$.

(A) In mosses,the capsule contains a specialized structure called the peristome.
The peristome consists of a ring of teeth-like structures known as peristome teeth.
These teeth are hygroscopic in nature,meaning they respond to changes in humidity.
When the air is dry,the peristome teeth bend outward,allowing the spores to be released and dispersed by the wind.
Therefore,the dispersal of spores in a moss capsule occurs through the peristome teeth.

(A) The $Funaria$ plant body represents the gametophyte stage,which is haploid $(n)$.
In $Funaria$,the sporophyte is dependent on the gametophyte and is diploid $(2n)$.
Therefore,the gametophyte is the haploid stage.

(B) The sporophyte of $Funaria$ is a partial parasite (semiparasite) on the gametophyte (moss plant). It remains attached to the gametophyte to obtain water,minerals,and certain growth factors,although it may contain some chlorophyll and perform limited photosynthesis.

(C) The peristome in $Funaria$ consists of two rings of teeth.
The outer ring of peristomial teeth is hygroscopic,meaning it absorbs moisture from the atmosphere.
This property allows the teeth to move in response to changes in humidity,which facilitates the gradual dispersal of spores from the capsule.

(D) In $Funaria$ (a moss),the sex organs are the $Antheridium$ (male) and $Archegonium$ (female).
After fertilization,the zygote is formed within the $Archegonium$.
The zygote undergoes mitotic divisions to develop into an embryo,which eventually differentiates into the sporophyte.
Therefore,the development of the sporophyte begins within the $Archegonium$.

(A) In $Funaria$ (a moss),the spore germinates to produce a juvenile stage known as the $Protonema$.
This $Protonema$ is a creeping,green,branched,and frequently filamentous stage in the life cycle of mosses.
It develops directly from the spore and eventually gives rise to the leafy gametophyte stage.

(B) The peristome in a moss capsule is typically differentiated into two concentric whorls of radially arranged teeth,known as the endostome and the exostome. Therefore,the total number of peristome whorls is $2$.

(D) In $Funaria$,the sporophyte is diploid $(2n)$.
Meiosis (reduction division) occurs within the spore mother cells located in the capsule of the sporophyte.
This process results in the formation of four haploid $(n)$ spores,which are the first cells of the gametophytic generation.

(C) The main plant body of $Riccia$ is gametophytic $(n)$,which is thallose,meaning it lacks true roots,stems,and leaves.
Since the gametophyte represents the haploid phase of the life cycle in bryophytes,the thallus of $Riccia$ is haploid.