division bryophyta and its land adaptations

hope well thanks for your great support in the previous segments of this blog so in this segment of this blog i would like to talk to talk about division bryophytes its structure structure its definition and such of the characteristics that bryophytes have developed for better survival on dry conditions such on land so and if you want to know anything related to biology so please let of known down in the comment section so
                          LETS START
it is though that the first plant to come on land and colonize on earth are bryophytes they are generally thought to be evolved from green algae due due their similarity with them
so habitat of bryophytes is known as the place where bryophytes generally live such that the bryophytes are poorly adapted to life on land and are mainly confined to damp moist and shad places
*these plants are devoid of special vascular bundles such that they dont have vascular bundles such as xylem and phloem tissues and other strengthening tissues only the process of diffusion helps in the transportation of food as well as the transportation water and minerals and some of the other substances 
*some of them have a thick and waxy cuticle some of them have a very thin cuticles and some of the bryophytes dont have a cuticle such that they have diversity related to cuticle 
*they are said to be amphibians(having dual nature) of green plants the reason is that they cannot live away from water as they need water for reproduction need water for the transformation of male gametes to female for the process of reproduction and also they are flowerless 
*these plants show a regular hetromorphic (morphological different) alternation of generation such that in them different generations alter with each other 
*gametophyte generation is dormant independent and free living 
*they may be thalloid as in many of the liverworts or is differentiated into structure resembling to stem leaves and absorbing and anchoring organs rhizoids as in some of the mosses and some of the liverworts the gametophyte produces a sporophyte which is a less conspicuous generation partially or totally dependent upon the gametophyte for its nutrition 
*in bryophytes the sporophyte generation generally consist of foot seta and capsule 
*the sporophyte is diploid (2n) which produces in sporangia one kind of haploid spores (such that it is homosporous) by meiosis
*the spores germinate to give rise to gametophyte which is also haploid 
*multi-cellular male ad female sex organs that is antheridia and archegonia respectively are born on gametophyte either on same plant or on different plant  
*these sex organs are multi cellular and is protected by a sterile covering of cells 
*gametes are produced by the cell division known as the mitosis 
*male gametes produced within antheridia are called antherozoids such that antherozoids are motile and is always produced in large number 
*female gametes are found within archegonia and are termed as the eggs 
*such that only a single egg is formed in each archegonia 
*fertilization takes place in water antherozoids (n) are attracted towards archegonia (n) chemotactially
*a single antherozoids(n) fuses with a single(n) thus accomplishing fertilization which results in the formation of the diploid zygote 2n
*the zygote is retained within the female sex organ (that is archegonium) for some of the time 
*after its resting period the zygote develops through mitotic division into a diploid embryo
*the embryo ultimately changes into a sporophyte which is a diploid 
*the entire development of sporophyte thus takes place within the gametophyte plant body 
*even when the sporophyte is fully developed it remains attached to the gametophyte for its nourishment and protection because it does not obtain chloroplast and is unable to perform photosynthesis
*there is a alternation of generation in the life cycle of bryophytes that is multicellur haploid gametophytes(gametes producing) generation alter with the multicellular diploid sporophyte (spores producing ) generation 
*it is a very important process which provides continuous genetic variability and selection for the best genetic make up for the survival and adaptions in the changing environments
so bryophytes are defined as vascular system absent gametophyte dormant sporophyte attached to gametophyte and is homosporous 
in general bryophytes developed following adaptive characters for the terrestrial environment 
conservation of water 
*formation of a compact multicellular body helps in conservation of water by reducing cell surface area exposed to dry land conditions 
*presence of cuticle further reduces loss of water by the process of evaporation 
development of photosynthetic tissue  
*development of photosynthetic tissues into special chambers for the adsorption of carbon dioxide without losing much of the water and much of the exposure to the sunlight 
formation of rhizoids
*there is formation of special structure structures in them that is known as the rhizoids that are used for the adsorption of water and for anchorage 
in them the process of heterogamy is evolved forming non motile eggs containing stored food and motile sperms 
protection of gametes 
gametes is produced and is protected by the special multicellular organs called antheridia and archegonia 
retention on embryo in archegonia 
multicellular embryo is formed which is retained and is protected inside the female reproductive body during its development 
alternation of generation 
alternation of spores producing generation that is sporophyte with gametes producing generation that is known as the gametophyte that enables the plant to produce and test the best combinations for the adaptions to the versatile terrestrial conditions 
      THANKS FOR READING                                      


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