Pdf chapter 21 meet the bryophytes forter jr puguon. Sex organs produce gametes to form a diploid zygote. The following diagram gives one example of a bryophyte life cycle, that of the moss funaria hygrometrica. This is the multicellular, haploid phase of the life cycle. Mosses are widely distributed from pole to pole and occupy a broad range of habitats. In the common haircap moss, polytrichum commune shown here, there are three kinds of shoots. Introduction to bryophytes pdf format download online e. If you know of any bryophyte books that are missing from the list please leave a message in the comments. The leafy shoot of mosses is haploid and thus part of the gametophyte generation. O the division pteridophyta includes primitive living and fossil vascular plants o they were originated in the silurian period and flourished in the devonian period. In bryophytes, where the two generations are morphologically different, the type of alternation of generations is known as heteromorphic. Like all land plants embryophytes, bryophytes have life cycles with alternation of generations. Bryophyte definition, characteristics, life cycle and examples.
Brochure on the bryophytes of northeastern connecticut. The bryophytes are fundamentally terrestrial plants but require presence of water to complete their life cycle. Mature gametophytes produce antheridia or archegonia, depending on sex. The life cycle of bryophytes is like all the other land plants embryophytes with alternation of generations. O bryophytes are terrestrial plants but require water at every stages in their life cycle. Bryophyte definition, characteristics, life cycle and.
These key innovations allowed plants to colonize the land, setting. Oct 04, 2019 bryophyte life cycle the bryophyte lifecycle consists of alternating generations between the haploid gametophyte and the diploid sporophyte. In the case of bryophytes the gametophyte generation is conspicuous and longerlived phase of the lifecycle in comparison to that of sporophyte generation. Moss reproduction can also be taught, as students will have the opportunity to see fertilization and sporophyte development firsthand.
Mosses together, mosses and liverworts comprise most of the phylum bryophyta. The gametphyte is haploid and an independent plant at maturity. The water is needed for dehiscence of antheridia, liberation of antherozoids, transfer of antherozoids from anthertdta to archegonia, opening of archegonial neck, and the movement of antherozoids into the archegonial neck. Read this lesson to learn about the surprisingly complex. Mosses, hornworts, and liverworts were once placed together in the division bryophtya.
Gametophytic and sporophytic phases are present in the life cycle of brophytes. The life cycle of marchantia shows regular alternation of two morphologically distinct phases. In this article we will discuss about the gametophytic phase, reproduction and sporophytic phase in the life cycle of riccia. Molecular evidence, however, led to a major revision of the groups taxonomy. The sporophyte plant produces spores, while the gametophyte bears gametes. This stands in direct contrast to the tracheophyte life cycle, in which the diploid stage is dominant. Fern spores are catapulted into the air, and the spores develop into heartshaped haploid gametophytes that contain both male and female sex organs. Quiz questions focus on types of bryophytes as well as bryophyte genetics and reproduction.
As do all plants, bryophytes alternate a gametophytic generation with a sporophytic one a sporic meiosis, a life cycle in which meiosis gives rise to spores, not. Sporophyte diploid generation is attached to and dependent on the gametophyte for the entire life cycle. Asexual reproduction does not involve any sex cells or gametes. Bryophyta characteristics, life cycle and examples of. In the life cycle of gymnosperms, the dominant sporophyte phase alternates with the short gametophyte phase. In addition to being nonvascular, bryophytes have a set of common features that help to distinguish them from all other land plants. Like liverworts and hornworts, mosses possess a gametophytedominated life cycle. Bryophyte, traditional name for any nonvascular seedless plantnamely, any of the mosses division bryophyta, hornworts division anthocerotophyta, and liverworts division marchantiophyta. Unlike vascular plants, in bryophytes the haploid gametophyte 1n is the dominating generation. In the case of bryophytes the gametophyte generation is conspicuous and longerlived phase of the life cycle in comparison to that of sporophyte generation. O few bryophytes are truly aquatic and underwater forms. The gameteproducing phase in the life cycle of a plant. The sporeproducing phase in the life cycle of a plant. But sporophytic phase is short lived and completely dependent upon gametophytes.
The study of plants is called botany or plant biology. British columbia has the highest bryophyte diversity in canada so this is a wonderful place to study them. Bryophytes evolved important advances in both phases of the land plant life cycle. Most bryophytes lack complex tissue organization, yet they show considerable diversity in form and. Bryophytes were a pivotal step in land plant evolution, and their significance in the regulation of ecosystems and the conservation of biodiversity is becoming increasingly acknowledged. The life cycle of bryophytes contains an alternation of two stages or generations, known as the gametophyte and the sporophyte. Pteridophyta characteristics, life cycle, classification. In other it is externally differentiated into stem and leaves, however there are no roots. In each cycle, a haploid gametophyte, each of whose cells contains a fixed number of unpaired chromosomes, alternates with a diploid sporophyte, whose cell contain two sets of paired chromosomes. However, in pteridophytes, the main plant body is a sporophyte which is differentiated into true root, stem and leaves. Bryophytes, the secret plants that surround us duration. This page will start with the bryophyte life cycle in a nutshell. Whenever a spore germinates, it usually generates the protonema, which precedes the look of the more elaborately arranged gametophytic plant, the gametophyte, which.
The life cycle of pteridophytes is a continuous reproductive process that is dominated by the sporophyte sexual stage of the alternation of generations. The diversity increases at tropical and subtropical latitudes. In bryophytes such as the liverwort marchantia, gametophytes produce organs for sexual reproduction. Mosses, hornworts and liverworts all reproduce using spores rather than seeds and dont produce wood, fruit or flowers. The life history of bryophytes involves an alternation between sporophytic and gametophytic generations that differ in form and function. The sexuality of pteridophytic gametophytes can be classified as follows. Similar to the life cycle of seed plants, the pteridophytes also involves the alternation of generations in its life cycle. This basic life cycle is found in all nonseed producing plants including mosses and liverworts, horsetails genus equisetum, lycophytes genera lycopodium, isoetes, and selaginella, and ferns details of the life cycles in these groups differ. The plant body of riccia is gametophytic and gametophytes are fleshy, prostrate and dichotomously branched. The gametophytes of typical bryophytes are dieciousnthat is, they are either male or female. Bryophytes basic biology basic biology inspired by life.
Leaf through this article to get an insight about gymnosperm life cycle in detail. One of the generations is haplophase and the other is diplophase. These key innovations allowed plants to colonize the land, setting off a series of spectacular adaptive radiations, first among bryophytes and later in vascular plants. Gametophytic phase is long lived, independent, green, and freely branched. Mar 27, 20 bryophytes, the secret plants that surround us duration. Introduction to bryophytes introduction to bryophytes. The term bryophytes is a general, inclusive term for these three groups though they are only superficially related. Focus your answer on traits structures or processes that affect the success of various transitions in the life cycle. Their lifecycle is dominated by a gametophyte generation which provides support and. O they fail to complete its life cycle in the absence of water. Few of them grow in water and others in bogs, moist walls, rocks and tree trunks. The spores produced in a spore capsule are the result of sexual reproduction. Chapter 22 bryophytes university of california, davis.
Characteristics of bryophytes life cycle and reproduction. Diploid zygotes formed by the fusion of haploid sperm and. Nutrients absorbed through leaf cant grow tall water needed for fertilization use sperm, not pollen bryophyte characteristics haploid gametophyte dominate life form green, photosynthesizing diploid sporophyte shortlived depends on gametophyte for nutrients plant. Mosses alone now represent the division bryophyta, and hornworts and liverworts are placed in the divisions anthocerotophyta and marchantiophyta, respectively. Adapted by eike stubner based on figure by ladyofhats public domain, from wikimedia commons.
Bryophytes are plants that can be found all throughout the world. Life cycles of bryophytes, seedless vascular plants and gymnosperms essay sample. Like other plants, bryophytes change between two generations with different morphology and function heteromorphy. Life cycles of bryophytes advanced ck12 foundation. Gametophytes produce haploid sperm and eggs which fuse to form diploid zygotes that grow into sporophytes. Bryophytes are primitive land plants that grow on moist shady places. Plant body is gametophytic and consists of two different stages namely. Pteridophyte life cycle just as with bryophytes and spermatophytes seed plants, the life cycle of pteridophytes involves alternation of generations. Pteridophytes are characterized by a life cycle that usually involves an alternation of two freeliving generations sporophyte and gametophyte with the sporophyte the. Life cycles of bryophytes, seedless vascular plants and. Comparing thallophytes, bryophytes and tracheophytes.
The first structure formed from spores in most mosses and many liverworts is a filamentous, algallike. For more information about the life cycles of bryophytes and tracheophytes, see alternation of generations. Each of the haploid 1 n spores is capable of developing into a multicellular, haploid individual, the gametophyte. Nutrients absorbed through leaf cant grow tall water needed for fertilization use sperm, not pollen bryophyte characteristics haploid gametophyte dominate life form green, photosynthesizing diploid sporophyte shortlived depends on gametophyte for nutrients plant life cycle gametophyte 1n. Though they started land life, they require presence of water to complete their life cycle for movement of motile male gametes antherozoids. It gives rise to diploid sporophyte, which however contains twice the number of paired chromosomes. The bryophyte life cycle bryophyte generations alternate between a sporophytic generation, which means they use spores to reproduce, and a gametophytic generation, which means they use sperm and. Life cycle of marchantia with diagram hepaticopsida. The bryophyte lifecycle consists of alternating generations between the haploid gametophyte and the diploid sporophyte.
Mar 08, 2016 you may recall that in bryophytes the dominant phase in the life cycle is the gametophytic plant body. Multiple choice questions on bryophytes mcq biology. In this article we will discuss about the gametophytic phase, reproduction and sporophytic phase in the life cycle of funaria. As do all plants, bryophytes alternate a gametophytic generation with a sporophytic one a sporic meiosis, a life cycle in which meiosis gives rise to spores, not gametes. Female, which develop archegonia at their tip a single egg forms in each archegonium male, which develop antheridia at their tip. Bryophytes mosses, hornworts, and liverworts can be found in all ecosystems of earth.
Repeated dichotomy results into a typically rosette like appearance figs. These organs possess welldifferentiated vascular tissues. During the gametophyte stage, haploid gametes male and female are formed in the specialized sex organs. In marchantia this phase is dominant and produces the sex organs. Bryophytes are a type of green plant that includes the mosses, liverworts, and hornworts. Using mosses in the classroom, students can see phenomena such as the formation of antheridia, the male sex organs, and archegonia, the female sex organs. The basic bryophyte life cycle begins with a haploid 1 n spore that germinates on moist soils and grows into a haploid gametophyte, the dominant life cycle stage. O bryophytes are quite uncommon in marine environments. However, the pteridophytes differ from mosses and seed plants in that both generations are independent and freeliving.
A haploid gametophyte cell contains a fixed number of unpaired chromosomes. Transfer of pollen from the anther to the stigma of a plant. O they are known as vascular cryptogams cryptogams with vascular system o they show heteromorphic alternation of generation with prominent sporophytic and gametophytic phases. Read this lesson to learn about the surprisingly complex life cycle these plants have. A haploid cell has one set of chromosomes, a diploid cell has two. Thesporophyte each sporophyte is divided into foot, seta and capsule the archegonia are ranged in 8radiating rows on lowersurfaceofdisc.
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