BIO NOTES & FACTS

Bryophyta  Mosses  Characteristics:-  They mostly prefer moist and shady habitats Their plant body is simple: They don't produce their own seeds or flowers, They have simple leaves which is covered with thin stems, They have root-like structures, Rhizoids  Like liverworts, the gametophyte is the predominant stage in the life cycle of mosses Gametophyte:- it consists of 2 stages Protenema It develops from a spore, They are green, creeping and branched structure Leafy stage (final gametophyte)  It develops from secondary protonema, They have an upright axis with spirally arranged leaves  Examples;- Funaria, Sphagnum, Common hair cap moss  Reproduction:- Asexual reproduction Fragmentation:- Stems, leaves from the moss accidentally broken off can regenerate to form a new plant. Budding:- New individual is formed as an outgrowth  of the parent, Daughter separates away and parent continues to exist  Sexual reproducti...

Bryophyta Body differentiation exists:- They have stem-like and leaf-like structure  These are known as plant amphibians because even if they live in soil but they need water to complete their life cycle. water is something which is mandatory for them.  They are mostly found in moist hilly areas the specialized vascular tissue is  absent in them  They play a very significant role in preventing soil erosion They have hidden reproductive system-cryptogamae Example; Mosses, hornworts, liverworts Structure  Here body differentiation exists  They are erect with unicellular/ multicellular rhizoids (Rhizoids: -Hair-like structures from the lower epidermal cells  of bryophytes )  There are no true roots/stem/leaves  Reproduction Asexual reproduction:- They reproduce asexually through fragmentation Spore formation Sexual reproduction:- Gametophyte (plants which produce gametes ) Male gamete - Anthero...

Thallophyta These are the plants with no body differentiation They do have a specific root, stem, leaves so they do not have specific differentiation   They prefer aquatic habitats examples :-green algae In thallophyta they have a hidden reproductive system -cryptogamae Algae They are autotrophic  Habitat :- Mostly aquatic (freshwater/ marine )  , found in most soil/ wood  Structure :- It can be unicellular,colonial, filamanteous  Examples :-volvox ( colonial ), Chlamydomonas (unicellular ), Ulothrix (filamenteous ), Spirogyra ( filamenteous ), Ulva, Cladophora (branched filaments) it is also known as river weed Algae reproduction  Asexual reproduction :- Fragmentation Parent organism will break into new pieces or multiple pieces on maturity, each of which give rise to a new individual. Example :- spirogyra when it  becomes matures it breaks into new pieces and each of these pieces are able to give rise to a ne...

P LA NT  KINGDOM Plantae : characterstics Eukaryotes :-specific membrane bound cell organelle & distinct nucleus  Multicellular :- they are  made up of multiple cells  Autotrophic :- prepare their own food  Immobile  They can be aquatic or land plants  Their cell walls are present Classification system  Artificial Natural Phylogenetic Artificial classification system   External morphological characters  Advantages :-closely related species could be classified  Limitations :- Equal weightage to vegetative and sexual characterstics Natural classification system  External as well as internal characters are the basis of classification Advantages :-overshadows limitations of artificial system                        Establishes relationship between organism  Limitations :-closely related organism can differ in important p...