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Dandruff and ring worm.

Water is essential for bryophytes to complete their life cycle. So they are called as amphibians of the plant kingdom.

Classification of plant kingdom :

Artificial System of Classification 

• Based on a few characteristics. 

• e.g., By Carolous Linnaeus, based on androecium structure 

Natural System of Classification 

• Based on natural affinities among organisms 

• Included external as well as internal features 

• e.g., By George Bentham and J. D. Hooker 

Phylogenetic System of Classification 

• Based on evolutionary relationships between the various organisms 

• e.g., By Hutchinson

Male and female gametophyte have free existence in bryophytes and pteridophytes but not in Gymnosperms.

Algin is a kind of complex sugar found in brown algae.

Lower part of moss capsule is known apophysis.

Bromine is obtained from Rhodomela.

Gelidium – Agar.

Palmella stage is formed in response to desiccation condition and toxic salts.

The pigments responsible for brown colour are xanthophyll and fucoxanthin.

Selaginella.

Hold   fast. 

Thallus refers to a plant body which is not differentiated into roots, stem and leaves. 

Example: Algae.

Correct answer is (2) a, b

Pteridophytes

Mucopolysaceharides over the cellulosic cell wall of brown algae such as agar, carrageenin, alginates etc, are known as phycocollolds.

(d) Mutualism

Riccia is the bryophyte in which sporogonium is embedded in the thallus.

Antheridium. 

Plant body of bryophyte produces gametes in their sex organs. So it is gametophyte.

Bryophytes are commonly called “Amphibians of Plant Kingdom”.

If stamens are attached to petals, then the stamens are called epipetalous.

If stamens are attached to petals, then the stamens are called epipetalous.

The method of arrangement of ovules on the placenta in the ovary is called placentation / Arrangement of ovules on the placenta in the ovule is termed placentation.

• Carried out using computers 

• Based on all observable characteristics 

• Data processed after assigning number and codes to all the characters. 

Advantage : Each character gets equal importance and a number of characters can be considered.

’The condition in which the anthers and filaments are fused is termed synandry.

Fusion of one of the male gametes with the egg are the second male gamete with the secondary nucleus is called double fertilization. OR The participation of two male gametes in two fertilization is called double fertilization. 

Pollination by wind is called anemophily. Pollination by birds is called omithophily.

Fusion of one of the male gametes with the egg are the second male gamete with the secondary nucleus is called double fertilization.

OR

The participation of two male gametes in two fertilization is called double fertilization.

tallest tree species : Sequoia 

Pteridophytes. As the possess vascular tissues - xylem and phloem.

Gemma are green, multicellular, asexual buds which develop in receptacles called as gemma cups. 

The seeds of gymnosperms are naked whereas the seeds of angiosperms are covered by fruits.

 The seeds of gymnosperm are naked, while those of angiosperms are covered. Hence, they are kept in different groups.

 Economic Importance of Algae:

• Almost 50% of carbon fixation on earth is carried out by algae. Thus, they are among the large producers on the earth; especially in aquatic habitat. About 70 species of marine algae are used as food, e.g. Porpyra, Laminaria and Sargassum.

• Some marine brown and red algae produce large amounts of hydrocolloids. Hydrocolloids are water holding substances and are used commercially.

• Agar; which is obtained from Gelidium and Gracilaria is used as culture medium in laboratories. It is also used in making ice-cream and jelly.

• Chlorella and Spirullaina are used as food supplements; even during space travel. 

Economic Importance of Gymnosperms:

• They are widely used as ornamental plants. 

• Fibres from conifer are used as paper pulp.

• Conifers are widely used in reforestation projects. 

• Turpentine and rosin are made from conifer resin. 

• Commercially useful oils are produced from many conifers, e.g. juniper, pine, fir, etc.

Importance of Algae :

• At least half of the total carbon dioxide fixation on earth carried out by them. 

• Increase oxygen level in the environment. 

• Many species like Laminaria, Sargassum etc. are used as food.

• Agar obtained from Gelidium and Gracilaria is used in ice-creams and jellies. 

• Algin obtained from brown algae are carrageon from red algae used commercially. 

• Chlorella and Spirullina are unicellular algae, rich in protein and used even by space travellers.

• Based on cytological information. 

• Gives importance to chromosome number, structure and behaviour.

Megasporophylls are the structural components of female cone. They produce megasporangium or ovules. Microsporophylls are the structural components of the male cone. They produce microsporangia.

If filaments of stamens are united and anthers are free then it is called adelpy. 

The unit of pistil is a carpel. 

Sterile stamens are staminodes.

Gymnos (naked) spermia (seeds). Gymnosperms are therefore called naked seed plants.

Cycas – Class Cycadopsida

(i) Anthoceros – Bryophyte – thalloid and dominant gametophyte 

(ii) Funaria – Bryopsida – Sprophyte parasitic on gametophyte.

Even though bryophytes live on land they need water for fertilization.

The sperms of bryophytes are motile, hence require water for swimming. 

Heterospory is a phenomenon in which two kinds of spores are borne by the same plant. These spores differ in size. The smaller one is known as microspore and the larger one is known as megaspore. The microspore germinates to form the male gametophyte and the megaspore germinates to form the female gametophyte. The male gametophyte releases the male gametes and these reach the female gametophyte to fuse with the egg. The development of the zygote takes place inside the female gametophyte.

E.g., Salvinia and Selaginella produces two kinds of spores

(i) macrospores: these are large in size, 

(ii) microspores : these are small in size. These pteridophytes are heterosporous.

Significance:

(a) The mega and microspores germinate and then give rise to male and female gametophytes.

(b) The female gametophyte is retained on parent sporophyte for variable period of time.

(c) The development of zygote into young embryo occurs within female gametophyte.

Homospory and Heterospory With Example:

In ferns, the underground stem is called as rhizome.

A structure consisting of curved teeth in the capsule of Funaria is termed as peristome.