Mix Examples- Plant Kingdom Questions in English

(D) Phanerogams are seed-bearing plants.
Both gymnosperms and angiosperms produce seeds,whereas pteridophytes are cryptogams (seedless plants).
Therefore,both $(b)$ and $(c)$ are grouped under phanerogams.

(B) In the five-kingdom classification system,land plants (Kingdom Plantae) are broadly categorized based on the presence or absence of vascular tissues.
$1$. Bryophytes are non-vascular land plants that lack true xylem and phloem.
$2$. Tracheophytes are vascular land plants that possess specialized vascular tissues (xylem and phloem) for the conduction of water and nutrients.
Therefore,land plants are classified into Bryophyta and Tracheophyta.

(D) The group $Embryophyta$ consists of all land plants that produce a multicellular embryo during their life cycle.
This group includes $Bryophyta$, $Pteridophyta$, and $Spermatophyta$ (Gymnosperms and Angiosperms).
Since all these groups possess a well-developed embryo from which the new plant originates, the correct answer is $All \text{ the above}$.

(D) The term 'fission algae' is commonly used to refer to $Schizosaccharomyces$ (a yeast) or certain algae that reproduce primarily by fission. Among the given options,none of these are specifically classified as 'fission algae'. $Nostoc$ is a cyanobacterium,$Oedogonium$ is a filamentous green alga,and $Volvox$ is a colonial green alga. Therefore,the correct option is $D$.

(D) The condition described is known as the dikaryotic phase $(n+n)$.
In the life cycle of Basidiomycetes,plasmogamy (fusion of protoplasm) results in a dikaryotic cell where two nuclei from different mating types exist together.
These nuclei do not fuse immediately (karyogamy is delayed) but divide simultaneously as the mycelium grows,maintaining the dikaryotic condition in each new cell.
Therefore,the fungus belongs to the class Basidiomycetes.

(A) Algae differ from $Bryophyta$ primarily in the structure of their reproductive organs.
In algae,the sex organs are typically unicellular and naked,meaning they lack a sterile protective layer.
In contrast,$Bryophyta$ possess multicellular sex organs that are covered by a sterile jacket of cells,which provides protection to the developing gametes.
Therefore,the correct distinction is that algae possess naked sex organs.

(C) Thallophytes are a group of plants that have a simple,undifferentiated body structure known as a thallus.
This group primarily includes algae,which are photosynthetic and autotrophic.
However,the group also includes fungi,which are heterotrophic as they lack chlorophyll and cannot perform photosynthesis.
Therefore,thallophytes can be either autotrophic (like algae) or heterotrophic (like fungi).

(D) The term $Thallophyta$ refers to a group of plants that have a simple,undifferentiated body structure known as a $thallus$. In the traditional classification system,$Thallophyta$ primarily includes organisms like $Algae$ and $Fungi$. $Bryophyta$ are excluded from this group as they possess a more complex body structure compared to $thallophytes$.

(D) $Equisetum$,$Selaginella$,and $Marsilea$ are all examples of pteridophytes. None of these belong to the group Algae. Therefore,the correct option is $D$.

(A) $Spirogyra$ is a green alga that reproduces sexually via conjugation,where the gametangia are typically uninucleate.
In contrast,$Mucor$ is a zygomycete fungus that forms multinucleate gametangia during sexual reproduction.
Therefore,the primary difference mentioned in the options is that $Spirogyra$ possesses uninucleate gametangia,whereas $Mucor$ possesses multinucleate gametangia.

(C) In $Ulothrix$,the life cycle is haplontic.
The zygote $(2n)$ is the only diploid stage in the life cycle.
During favourable conditions,the zygote undergoes meiosis (reduction division) to produce haploid zoospores or aplanospores.
Therefore,meiosis occurs during the germination of the zygote.

(D) In $Bryophytes$,vascular tissues (i.e.,$xylem$ and $phloem$) are completely absent.
Water and nutrients enter cells by diffusion,whereas in $pteridophytes$,vascular tissues consist of $xylem$ (without true vessels) and $phloem$ (without companion cells).

(B) The correct answer is $B$.
Both gametophytes and sporophytes in mosses and ferns contain chlorophyll.
This allows them to perform photosynthesis,making them autotrophic in their mode of nutrition.
While their independence varies between the two groups,the ability to synthesize their own food via autotrophic nutrition is a shared characteristic.

(B) $Funaria$ is a bryophyte,while $Pinus$ is a gymnosperm.
$Pinus$ (gymnosperm) produces seeds,whereas $Funaria$ (bryophyte) does not produce seeds.
Therefore,the absence of seeds is a key characteristic that differentiates $Funaria$ from $Pinus$.

(D) Thallophyta is a division of the plant kingdom where the plant body is not differentiated into roots,stems,and leaves,commonly referred to as a thallus.
$Spirogyra$ is an alga,which belongs to Thallophyta.
$Mucor$ is a fungus. Although fungi were historically grouped with plants,they are now classified in a separate kingdom,Kingdom Fungi. However,in the context of traditional botanical classification,they are often excluded from Thallophyta.
$Moss$ $(Funaria)$ belongs to the division Bryophyta,where the plant body is differentiated into stem-like and leaf-like structures,and it is not thalloid.
Therefore,both $Mucor$ and $Moss$ are not members of Thallophyta.

(C) Birbal Sahni was a renowned Indian paleobotanist.
He is widely recognized for his significant contributions to the study of fossil plants.
He established the Birbal Sahni Institute of Palaeosciences in Lucknow,$(UP)$,and is particularly famous for his description of the fossil plant genus $Williamsonia$ $sewardiana$.

(A) The correct answer is $A$.
Algae,bryophytes (mosses),and pteridophytes (ferns) require an external source of water for the process of fertilization.
This is because their male gametes (sperms) are flagellated and motile,meaning they require a water medium to swim and reach the female gamete (egg) to complete fertilization.

(C) Both bryophytes and pteridophytes require water for the process of fertilization. In these plant groups,the male gametes (antherozoids) are flagellated and motile,meaning they require a film of water to swim to the female gamete (egg) located within the archegonium.

(A) Mosses (Bryophytes) and ferns (Pteridophytes) are found in moist and shady habitats because they require water for the process of fertilization.
In these plants,the male gametes (antherozoids) are flagellated and motile,and they need a film of water to swim to the female gamete (egg) to achieve fertilization.
Therefore,the presence of water is an essential external factor for their sexual reproduction.

(B) The correct answer is $B$ (Tracheophyta).
Tracheophyta,or vascular plants,are considered the most important group of plants on Earth.
They possess specialized vascular tissues,$Xylem$ and $Phloem$,which allow them to transport water and nutrients efficiently over long distances.
This adaptation enabled them to grow to large sizes and colonize diverse terrestrial habitats,forming the basis of most terrestrial ecosystems.
They include ferns,gymnosperms,and angiosperms,which provide food,oxygen,shelter,and raw materials for human civilization.

(D) $Funaria$ is a bryophyte,while $Pteris$ is a pteridophyte.
In bryophytes $(Funaria)$,the main plant body is the gametophyte,and the sporophyte is dependent on the gametophyte.
In pteridophytes $(Pteris)$,the main plant body is the sporophyte,which is independent and dominant.
Therefore,$Pteris$ differs from $Funaria$ by having a dominant sporophytic phase.

(B) In the life cycle of mosses $(Bryophytes)$,the dominant phase is the gametophyte. The protonema is a filamentous stage of the gametophyte.
In $Dryopteris$ $(Pteridophytes)$,the main plant body is the sporophyte. The prothallus is a small,multicellular,free-living,photosynthetic,thalloid structure which represents the gametophytic phase.
Therefore,both the protonema of moss and the prothallus of $Dryopteris$ are gametophytic in nature.

(A) $Funaria$ is a bryophyte,while $Selaginella$ is a pteridophyte.
$Selaginella$ possesses true roots,whereas $Funaria$ lacks true roots and instead has root-like structures called rhizoids.
Both $Funaria$ and $Selaginella$ produce an archegonium (female sex organ),form an embryo after fertilization,and have motile sperms (antherozoids) that require water for fertilization.
Therefore,roots are not common to both.

(D) In heterosporous pteridophytes like $Selaginella$,the megaspores and microspores are retained and germinate within the sporangia to form female and male gametophytes,respectively.
In gymnosperms like $Pinus$,the development of the male gametophyte (pollen grain) occurs within the microsporangium,and the female gametophyte develops within the megasporangium (ovule).
Therefore,both $Selaginella$ and $Pinus$ exhibit the phenomenon where the primary development of gametophytes occurs within the sporangia.

(D) The main plant body of both gymnosperms and angiosperms is a sporophyte,which is differentiated into true roots,stems,and leaves.
- Option $A$ is incorrect because companion cells are characteristic of angiosperms only.
- Option $B$ is incorrect because in gymnosperms,the endosperm is haploid and formed before fertilization,whereas in angiosperms,it is triploid and formed after fertilization.
- Option $C$ is incorrect because gymnosperms have naked seeds,while angiosperms have seeds enclosed within fruits.
- Therefore,the correct similarity is that both possess well-developed vegetative structures like roots,stems,and leaves.

(A) Ferns (Pteridophytes) and Cycas (Gymnosperms) both exhibit a characteristic developmental feature known as circinate vernation,where the young leaves are coiled like a watch spring.
This feature is a primitive trait shared between certain pteridophytes and cycads.
While pollen tubes are found in Cycas,they are absent in most ferns.
Ovules and seeds are characteristic of Gymnosperms (Cycas) but are absent in Pteridophytes (ferns).

(C) Both angiosperms and gymnosperms exhibit $Siphonogamy$.
In this process,the male gametes are transported to the female gametes (or archegonia) through a pollen tube.
While angiosperms typically have double fertilization and triploid endosperm,and gymnosperms have haploid endosperm,both groups share the common feature of using a pollen tube for fertilization.

(D) Phanerogams are seed-bearing plants.
Both gymnosperms and angiosperms produce seeds,whereas pteridophytes are cryptogams (non-seed-bearing plants).
Therefore,both $(A)$ and $(B)$ are classified as phanerogams.

(C) The correct answer is $C$.
In bryophytes and pteridophytes,fertilization is dependent on water.
The movement of male gametes (antherozoids) towards the archegonia is a chemotactic response.
Archegonia of $Pteris$ secrete specific chemical substances,primarily malic acid,which act as a chemoattractant.
This chemical specifically attracts the sperms of $Pteris$ through chemotaxis,ensuring species-specific fertilization.

(B) Heteromorphic alternation of generations refers to a life cycle where the sporophyte and gametophyte generations are morphologically distinct from each other.
In $Funaria$ (a bryophyte),$Selaginella$ (a pteridophyte),and $Cycas$ (a gymnosperm),the sporophyte and gametophyte phases are morphologically different.
$Spirogyra$ and $Rhizopus$ are algae and fungi respectively,which do not exhibit this specific type of alternation of generations in the same manner as land plants.

(B) The correct answer is $B$. In $Pteris$ (a fern),the antheridium produces numerous multiflagellated,coiled antherozoids. Similarly,in $Cycas$ (a gymnosperm),the male gametes (antherozoids) are large,top-shaped,and multiciliated (multiflagellated). In contrast,bryophytes like $Riccia$,$Funaria$,and $Marchantia$ typically possess biflagellated antherozoids.

(D) $Zea$ (maize) is a monocotyledonous plant, which possesses $1$ cotyledon.
$Cycas$ is a gymnosperm that typically has $2$ cotyledons in its embryo.
$Pinus$ is a gymnosperm that exhibits polycotyledony, meaning it has many cotyledons in its embryo.
Therefore, the correct sequence is $1, 2, \text{many}$.

(A) The correct matches are as follows:
$(A)$ Peritrichous flagellation: $Escherichia \text{ } coli$ $(L)$. Bacteria with flagella distributed over the entire surface are called peritrichous.
$(B)$ Living fossil: $Ginkgo$ $(J)$. $Ginkgo \text{ } biloba$ is a classic example of a living fossil.
$(C)$ Rhizophore: $Selaginella$ $(M)$. $Selaginella$ possesses a specialized root-bearing organ called a rhizophore.
$(D)$ Smallest flowering plant: $Wolffia$ $(N)$. It is a genus of tiny aquatic plants known as watermeal.
$(E)$ Largest perennial alga: $Macrocystis$ $(K)$. It is a giant kelp that can grow to massive lengths.
Therefore, the correct sequence is $A-L, B-J, C-M, D-N, E-K$.

(B) Plants such as Pteridophytes and Bryophytes rely on spores for reproduction and dispersal.
Unlike seeds,which contain a food reserve and a protective coat allowing for long-distance survival and dispersal,spores are unicellular and lack these protective mechanisms.
Therefore,these plants have a more limited distribution compared to seed-bearing plants (Gymnosperms and Angiosperms) because their spores require specific environmental conditions,such as moisture,to germinate and survive.

(D) The xylem of most gymnosperms lacks vessels (tracheids are present instead),and the phloem lacks companion cells (albuminous cells are present instead). Similarly,Pteridophytes also lack these specialized structures. Therefore,both vessels and companion cells are absent in both Pteridophyta and Gymnosperms.

(D) In many bryophytes and pteridophytes,the apical cell responsible for the growth of the gametophyte or sporophyte is typically tetrahedral or pyramid-like in shape. This shape allows for the production of daughter cells in three or four directions,facilitating the three-dimensional growth of the plant body.

(C) Complex tissues,such as xylem and phloem,are specialized tissues responsible for conduction and mechanical support in vascular plants.
$(c)$ All gametophytes are haploid structures that produce gametes and are typically composed of simple parenchymatous cells,lacking complex vascular tissues like xylem and phloem.

(B) Centrioles are typically absent in higher plants such as $Angiosperms$ and $Gymnosperms$.
However,they are present in the cells of certain lower plants,specifically in the motile stages of $Moss$ and some $Ferns$ (pteridophytes),where they are involved in the formation of flagella or cilia.
Therefore,the correct option is $B$.

(C) The minimum haploid number $(n)$ of chromosomes in the plant kingdom is $1$. This is observed in the species $Haplopappus$ $gracilis$,which has a diploid number $(2n)$ of $4$,meaning its haploid number $(n)$ is $2$. However,the absolute minimum haploid number of $n = 1$ is found in certain plants like $Mucor$ (though a fungus) or specific reduced chromosome sets in experimental botany. In the context of standard botanical records for vascular plants,$n = 2$ is often cited,but $n = 1$ is the theoretical and observed minimum in specific biological contexts.

(B) The movement of a motile organism or cell in response to a chemical stimulus is called chemotaxis.
In bryophytes and pteridophytes,the archegonia release specific chemical substances (exudates) that attract the male gametes (sperms) towards the archegonial neck.
Since the sperms are motile and their movement is directed by a chemical gradient,this phenomenon is specifically termed as chemotaxis.

(D) $Aldrovanda$ is a free-floating aquatic carnivorous plant.
$Vallisneria$ is a submerged aquatic plant that exhibits hydrophily (pollination by water).
$Sancatia$ is also recognized as an aquatic plant species.
Therefore,all the given options are adapted for an aquatic habitat.

(A) In the Bentham and Hooker system of classification,the subclass $Gamopetalae$ is divided into three series: $Inferae$,$Heteromerae$,and $Bicarpellatae$. The options $Thalamiflorae$,$Disciflorae$,and $Calyciflorae$ are the three series belonging to the subclass $Polypetalae$. Therefore,$Superae$ (often referred to as $Inferae$ in this context) is the correct series belonging to $Gamopetalae$.

(A) The classification system proposed by Bentham and Hooker divides Dicotyledonae into three subclasses: $1$. Polypetalae,$2$. Gamopetalae,and $3$. Monochlamydeae.
Within the subclass Polypetalae,there are $3$ series: Thalamiflorae,Disciflorae,and Calyciflorae.
However,the question refers to the classification structure where the subclass Polypetalae is divided into $8$ series (Thalamiflorae,Disciflorae,Calyciflorae,Heteromerae,Bicarpellatae,Inferae,etc.,across different subclasses).
Specifically,the Bentham and Hooker system is noted for its hierarchical structure where the subclass Polypetalae is divided into $3$ series,but the entire Dicotyledonae group is organized into series and families without the formal rank of 'Order' as used in modern systems. Among the options provided,Thalamiflorae is a series within Polypetalae.

(A) The series $Inferae$ is part of the $Bentham$ and $Hooker$ classification system for seed plants. It includes $3$ orders: $Asterales$,$Campanales$,and $Rubiales$.

(C) In the Bentham and Hooker system of classification,the sub-class $Polypetalae$ is divided into three series: $Thalamiflorae$,$Disciflorae$,and $Calyciflorae$.
$Inferae$ is a separate sub-class within the class $Dicotyledonae$ in this system,not a series within $Thalamiflorae$.
Therefore,$Inferae$ is the correct answer.

(D) Plants that produce seeds are collectively known as $Spermatophytes$.
$Spermatophytes$ include two major groups: $Gymnosperms$ (naked-seeded plants) and $Angiosperms$ (flowering plants).
Therefore,both $Gymnosperms$ and $Angiosperms$ are seed-bearing plants.

(D) In the haplodiplontic life cycle,both the haploid and diploid phases are multicellular and often free-living.
This pattern is characteristic of Bryophytes and Pteridophytes.
In Bryophytes,the dominant phase is the gametophyte $(n)$,while in Pteridophytes,the dominant phase is the sporophyte $(2n)$.
Therefore,both groups exhibit a haplodiplontic life cycle.

(D) Recent researchers and taxonomists have classified the Plant Kingdom into $5$ major groups: $1$. Algae,$2$. Bryophytes,$3$. Pteridophytes,$4$. Gymnosperms,and $5$. Angiosperms. This classification is based on the evolutionary complexity and reproductive structures of the plants.

(D) The plant kingdom is broadly classified into two main groups: Cryptogams (non-flowering plants) and Phanerogams (flowering plants).
Cryptogams are plants that do not produce seeds or flowers.
They are further divided into three main groups based on their body structure and complexity:
$1$. $Thallophyta$: Simple body structure,not differentiated into roots,stems,and leaves.
$2$. $Bryophyta$: Small,non-vascular plants that lack true roots,stems,and leaves.
$3$. $Pteridophyta$: First vascular plants that possess true roots,stems,and leaves but do not produce seeds.
Therefore,all the given options are groups of Cryptogams.