www.selectialindia.com KINGDOM - PLANTAE
All the multicellular eukaryotic plants are placed in Kingdom-Plantae.They are autotrophic i.e. they manufacture their food by photosynthesis.
Following plant groups are included in Kingdom-Plantae
( 1 ) ALGAE ( 2 ) BRYOPH Y TA (3) PTERIDOPHYTA
( 4 ) GYMNOSPERM ( 5 ) ANGIOSPERM
ALGAE
Term "Algae" was given by Linnaeus.
Phycology - Study of algae.
Father of Phycology - Fristch Book "Structure & Reproduction of algae"
Father of Indian phycology - M.O.P. Iyengar
NATURE -
(1) Algae are found in both fresh and marine water.
(2) Algae are found in many forms like filamentous, colonial.
(3) Algae are surrounded by mucilagenous sheath and below the sheath cell wall is present which is made up of cellulose and pectin but mainly made up of cellulose, galactans, mannans and mineral like calcium carbonate.
(4) On the basis of structure, algae are thalloid i.e. plant body is not differentiated into root, stem and leaves. Tissue system is also absent in algae.
(5) On the basis of nutrition, algae are photoautotrophic. They have chloroplast in which photosynthetic pigments are present. Classification of algae is mainly based on pigments. Chl-a and carotene are universal pigment of algae.
REPRODUCTION
( 1 ) Vegetat ive ( 2 ) As exual ( 3 ) Sexual
Vegetative reproduction :-
(i) Binary fission - Cell is divided into two parts and nucleus is also divided into two parts by mitosis.
eg. Found only in unicellular algae
(ii) Fragmentation - Filaments break down into small pieces & form new filaments.
eg. All filamentous algae
Asexual reproduction :-
Zoospores are formed in favourable conditions and Aplanospores, hypnospore and akinete etc. are formed in unfavourable condition.
Page 53 www.selectialindia.com Sexual reproduction :-
(i) Male sex organ is called antheridium and female is called oogonium. The sex organs of algae are unicellular & jacketless. But exceptionally sex organs of green algae Chara (Chara - green algae - known as stone wort)
are multicellular and Jacketed.
The male sex organ of Chara is known as globule and female is known as nucule.
(ii) Plant body of algae is haploid so sexual repro. take place through zygotic meiosis. So their life cycle is
haplontic.But exceptionally brown algae are diploid.
(iii) Algae reproduce by zygotic meiosis i.e. first division in zygote is meiosis so embryo is not formed.
Sexual repro. is of three types
( a ) Is og a mo us – Chlamydomonas debaryanum, Ulothrix, Ectocarpus, Spirogyra
(b ) Anisogamous – Chlamydomonas braunii
(c ) O og am ou s – Chlamydomonas coccifera, Sargassum, Volvox, Fucus
Note : (1) Chlamydomanas exhibits complete evolution of sexual reproduction.
(2) In Chlamydomonas debaryanum gametes are flagellated and similar in size.
(3) In Chlamydomonas braunii gametes are motile and dissimilar in size.
The classification of algae is mainly based on the photosynthetic pigments. In addition to this, cel l wall composition and stored food are also the base of classification.
Algae is divided into following divisions
( 1 ) CHLOROPHY TA - GREEN ALGAE
( 2 ) PHAEOPHY TA - BROWN ALGAE
( 3 ) RHODOPH YTA - RED ALGAE
Page 54 www.selectialindia.com CHLOROPHYTA Green Algae
Green algae are the most advanced algae. It is believed that green algae are the ancestors of the higher plants.
Habitat : Green algae are cosmopolitan in nature. Different forms of Green algae (Structure) : Green algae are found in many forms ( 1 ) Unicellular :- (i) Chlamydomonas - Motile unicellular algae. This algae moves with the help of flagella. (ii) Chlorella - Non motile unicellular alga.
Calvin discovered "Calvin Cycle" by experimenting on Chlorella. (iii) Acetabularia - Umbrella plant - It is the largest unicellular plant. The diameter of its cell is 10 cm.
Hammerling experimented on Acetabularia. Note : According to five kingdom system the algae described above should be placed in Protista but due to their life cycle is similar to green algae so they are studied in Plantae. ( 2 ) Colonial - Some green algae are found in colonies. They form colony of cells. The number of cells in a colony is fixed. Colony with fixed number of cells called coenobium. eg. Volvox - Motile colony ( 3 ) Multicellular filamentous - Mostly the green algae are multicellular and filamentous. eg. Ulothrix - Known as pond wool Spirogyra - Known as pond silk Note : some green algae are heterotrichous i.e. two types of branches prostrate and errect - Fritschiella, Stigeoclonium, Coleochaete (Fritschiella tuberosa has approch to the early land plants). ( 4 ) Multicellular thalloid or Parenchymatous - Some algae are multicellular in length & width. eg. Ulva - Also called as sea lettuce Photosynthetic pigments : Chlorophyll - Chl 'a' and Chl 'b' Carotene - carotene Xanthophyll - Luteaxanthin and Violoxanthin - Yellow coloured Notes : 1. On the basis of pigments (Chl 'a', Chl 'b', Carotenoids), stored food (starch) & cell wall (made up of cellulose or pectose), green algae are considered similar to higher plants. 2. Most of the members of green algae have starch as stored food and some have oil droplete also. 3. One or more pyrenoids are also present in chloroplast as storage bodies. Pyrenoids contain protein besides starch. Economic Importance : ( 1 ) Food - Chlorella is used as food, because after Spirulina, Chlorella has largest amount of protein. ( 2 ) Antibiotics - Chlorellin antibiotic is obtained from Chlorella. ( 3 ) Space research -
In space, Chlorella is used as a source of food and O2 by space travellers ( 4 ) Parasitic algae - Cephaleuros algae remains parasitically in the leaves of tea plant and causesdisease 'red rust'. Page 55 www.selectialindia.com PHAEOPHYTA Brown algae or Sea weeds
Brown algae are found in marine water.
Brown algae are multicellular filamentous.
Brown algae are the largest in size (upto 100 meter in length).
Largest brown algae - Macrocystis
The vegetative cells have a cellulosic wall usually covered on the outside by a gelatinous coating of algin.
Thallus of brown algae is divided into three parts :- (i) Lamina (frond) - Leafy part or photosynthetic part (ii) Stipe - Elongated tubes called trumpet hyphae are present for food conduction in stipe. Trumpet hyphae are analogus to sieve tubes of vascular plants. Due to lamina and stipe brown algae look like leaf (leafy algae). (iii) Hold fast - Help in attachement. e.g. Fucus, Dictyota, Ectocarpus
Pigments : Chlorophyll - Chl 'a' , Chl 'c' Carotene - Only carotene Xanthophylls - Mainly Fucoxanthin Note : The amount of Fucoxanthin is more in brown algae due to which these algae are brown in colour. (Xanthophylls are mostly yellow but fucoxanthin is brown) Stored food : Laminarin and mannitol - both are derivatives of carbohydrates. Phycocolloids :
On cell wall of brown algae some colloid substances like fucinic acid, alginic acid and fucoidin are present which are known as phycocolloids.
Phycocolloids protects brown-algae against dessication and shocks. Phycocolloids are used in ice-cream as thickening agent. Alginates, salts of alginic acid used for dentury measurement.
Alginates or Alginic acid - Obtained from Laminaria, Fucus, Macrocystis. Alginates are used in the manufacturing of soap, ice-cream, polish, cream and plastic.
Special Point : (1) Life cycle of Ectocarpus and kelps are diplohaplontic, life cycle of Fucus is diplontic. (2) Zoospores and gametes are pear shaped and have two unequal laterally attahced flagella. (3) Sex repro. may be brown algae isogamous, anisogamous or oogamons. Special name : ( 1 ) Sargassum - It is known as Gulf weed because Sargssum is a free floating alga. It grows rapidly in North Atlantic ocean and covers thousands of hectares of area. Therefore this region is called as sargasso sea. ( 2 ) Laminaria (Kelps) - It is called as Devil's Aprin. Iodine and Bromine - Obtained from Laminaria. Page 56 www.selectialindia.com RHODOPHYTA Red Algae
(1) Red algae are ancient algae
eg. Polysiphonia
(2) There is no motile stage found in life cycle of red algae and BGA i.e. cilia & flagella are absent.
(3) Red algae mainly found in marine water with greater concentration found in the warmer areas. But exceptionally Batrachospermum is found in fresh water (river) and Porphyridium is found on land.
(4) Red algae are multicellular but exceptionally Porphyridium is unicellular.
(5) Cell wall of red algae is complex and made up of cellulose & pectin.
The cell wall of red algae is also complicated like blue green algae. Their cell wall has many different type of substances such as xylan, galactose, polyuronic acid, polysulphate esters.
But in some algae calcium carbonate is also present in the cell wall. Due to which their thallus become stony. These algae form lime stone & coral reefs
e.g. Corallina and Lithothamnion Pigments :
Chlorophyll - Chl 'a' and Chl 'd'
Carotenes - carotene
Phycobilins - R - phycoerythrin (red coloured) and R - phycocyanin (blue coloured)
(1) On the basis of pigments red algae is similar to blue green algae.
(2) Colour of red algae changes according to depth in sea this is called as Gaudikov's effect.
(3) When red algae are present on the surface of the sea then their colour is blue and when they are at the bottom, their colour is red. At the surface of sea the amount of R - phycocyanin is more while in depth the amount of R - phycoerythrin is more.
Penetration power is maximum in ultra violet and violet light. R-phycoerythrin is only pigment to absorb ultra violet and violet light. Due to phycoerythrin red algae are deepest algae.
(4) Gaudikov's effect is also found in Blue - Green algae.
(5) Red algae not always red, it may be blue coloured also.
e g . Batrachospermum - This is a blue coloured algae. Stored Food :
Floridean starch - floridean starch is structurally similar to glycogen and amylopectin Phycocolloids :
Agar -Agar, carrageenin and funori phycocolloids are found in the cell wall of red algae. Reproduction :
( 1 ) Vegetative - By fragmentation
( 2 ) Asexual - Non motile spores [By monospore, carpospores, tetraspore]
Page 57 www.selectialindia.com ( 3 ) Sexual reproduction -
(I) Sexual reproduction is oogamous and accompanied by complex post fertilization developments.
(II) The female sex organs are called carpogonia.
(III) The male sex organs of red algae are known as spermatangia. Non motile spore like gametes are formed in spermatangia which are known as spermatia.
(iv) Life cycle of Polysiphonia is diplobiontic and Batrachospermum is haplobiontic Special points and Economic importance
( 1 ) Harveyella - It is a colourless parasitic alga. It remains as parasite on other alga.
( 2 ) Porphyra - It is an edible algae.
( 3 ) Gelidium and Gracilaria - Agar - Agar colloid is obtained from these. It is used to prepare culture medium to grow microbes and in prepartion of ice creams and Jellies.
( 4 ) Chondrus crispus - It is also called Irish moss. Carrageenin colloid is obtained from this alga. It is used as gelating agent in food industries (i.e. to make the food item viscous)
Capsule of medicines is also prepared from carrageenin. HABITAT OF SOME IMPORTANT ALGAE ( 1 ) Terrestrial - The algae found in moist soil & wall. eg. Terrentofolia ( 2 ) Epiphytes - Algae which are present on plants eg. Protococcus ( 3 ) Endophytes - Algae which are present inside plants eg. Coleochaete nitelum (in Nitella plant) ( 4 ) Epizoic - Algae which are present on animals eg. Cladophora (present on Mollusca shell) Cyanoderma and Trichophilus (Blue green algae) (Present on sloth bear) ( 5 ) Endozoic - Algae which are present inside the body of animals eg. Zoochlorella and Zooxenthellae (inside the Hydra) ( 6 ) Parasites - Algae that live as parasite and causes diseases eg. Cephaleuros (algae remains in the leaves of tea plant) Cephaleuros causes red rust disease of tea ( 7 ) Thermophilic - Algae found in hot water. eg. Chlorella ( 8 ) Cryophytes - Algae which are present in polar regions & Low Temperature. eg. Chlamydomonas (some species) Haematococcus nivalis (It develops red snow in polar region.) ( 9 ) Epiphloephytes - Algae arise on bark of trees.
Page 58 www.selectialindia.com THALLOPHYTA
(1) The term "Thallophyta" was given by "Endlicher". According to two kingdom classification, all the algae, fungi and prokaryotes were placed in thallophyta, because their plant body is thallus.
(2) In thallophyta the male sex organs are called as Antheridia and female sex organs are called as Oogonia. Sex organs are unicellular & Jacket less [Jacket - layer of sterile cells]
(3) The sexual reproduction in thallophyta is isogamous, anisogamous and oogamous.
(4) In thallophyta, sexual reproduction takes place through zygotic meiosis, therefore embryo is not formed.
Demerits of Two kingdom classification :
(1) In two kingdom classification Prokaryotes and Eukaryotes placed in the same group.
(2) In this system photosynthetic green algae and non photosynthetic fungi are placed in same group i.e. plantae.
(3) In two kingdom system unicellular and multicellular organism are placed together.
(4) On the basis of cell wall bacteria were considered as plant and put in plantae.
(5) Position of Euglena is not fixed.
Page 59 www.selectialindia.com BRYOPHYTA The term "Bryophyta" was proposed by "Robert Braun". The study of Bryophytes is known as Bryology. Hedwig is considered to be the father of Bryology. But according to some scientist it is believed that Cavers is the father of Bryology. Father of Indian Bryology is Prof. Shiv Ram Kashyap.
General characteristics : 1. Bryophytes are the first land plant. It is believed that, they originated from aquatic plant and they come on land through water. Because some bryophytes have characters similar to aquatic plants (eg. presence of air canal) 2. Bryophytes are known as amphibians of the plant kingdom, because these plants can live in soil but are dependent on water for fertilization. 3. Bryophytes are not considered as the successful land plants because vascular tissue is absent and they need water for fertilization. Due to the absence of vascular tissue bryophytes can not grow very tall. The process of water conduction in bryophytes takes place with the help of parenchyma. Parenchyma is a living tissue. 4. Roots are absent in bryophytes. Stem like and leaf like structure of bryophytes are functionally similar to the stem and leaves of higher plants. 5. Bryophytes are sciophytes, i.e. bryophytes prefer to grow in moist (wet) and shady places.
Life cycle of Bryophytes : 1. The main plant body of bryophyte is haploid. It produces gametes, hence is called a gametophyte. 2. Sex organs are formed on gametophyte. Sex organs are multicellular and jacketed in bryophytes. Male sex organs are called as antheridium and female sex organs are called as archegonium. Archegonium is flask shaped. 3. The male gametes of bryophytes are motile. These motile male gametes are called as antherozoids. Antherozoids are usually comma shaped and biflagellate. Female gamete is called egg.
Buds (n) GAMETOPHYTE (n) Protonema (n) Liver worts & Horn worts Antheridia Archegonia (n) (n) Germination
Mosses Gametophytic generation Antherozoids Egg (n) (n) Spores (n)
Zygote Sporic Meiosis Sporophytic generation (2n) Mitosis Spore mother cells Sporophyte Embryo(2n) (2n) (2n)
Page 60 www.selectialindia.com 4. In Bryophyta, fertilization is performed by zoodiogamy i.e. male gamete swims into water to reache the female gametes and fertilizes it.
5. Oogamous types of fertilisation is found in bryophytes. As a result of the fertilization, a diploid zygote is formed. Zygote does not undergo reduction division (meiosis) immediately) This zygote initiates the sporophytic generation. Sporophytic generation is a diploid stage.
6. Zygote formed sporophyte by mitosis, which is known as sporogonium.
Cell present in sporophyte function as spore mother cells. Now meiosis takes place in sproe mother cells, result of it haploid spores are formed.
7. The germination of spores is direct or indirect. In Liverworts & Hornworts the germination of spore is direct i.e. each spore forms a gametophyte after germination i.e. each spore forms one thallus.
But the germination of spores in Mosses is indirect. In mosses a multicellular filament is formed after the germination of spore. This filament is known as protonema. Now buds are formed on protonema. Each bud develops and form a gametophyte plant. Indirect germination is best for survival. Mosses are gregarious in nature because they appear in group.
Note : Protonema develop from spores is called as primary protonema and the protonema developed from parts other than spores are known as secondary protonema.
Sexual reproduction in bryophytes is oogamous type and life cycle is halplodiplontic type.
In Bryophyta the sporophyte is depend on gametophyte. This is a unique character of bryophyta. Bryophyta is divided in to three classes
1. Hepaticopsida 2. Anthocerotopsida 3. Bryopsida or Musci
HEPATICOPSIDA – LIVER WORTS
(i) All the bryophytes included in this class have shape like liver (eg. Marchantia) or flat (eg. Riccia) so they are known as liverworts.
(ii) Plant body of this group is thallus like and dorsiventral. Rhizoids and scales are present on thallus.. Rhizoids are unicellular and unbranched. Scales are multicellular.
(iii) The leafy members (eg Porella) have tiny leaf like appendages in two rows on the stem like structures.
(iv) The sporophyte of Liverworts is completely depend on gametophyte i.e. it is depend on gametophyte for food, water and habitat.
(v) The sporophyte of Liverworts is made up of foot, seta and capsule. (Except Riccia sporophyte is made up of only capsule).
(vi) Elaters are present in sporophyte of some members of liverworts. (eg. Marchantia - In Marchantia nurse cells are modified in to elaters) Elaters are hygroscopic and they help in dispersal of spores.
Eg. of Liverworts -
Riccia, Marchantia , Cryptothallus, Riella, Pellia, Porella Page 61 www.selectialindia.com Note : (1) In Bryophytes, sporophyte of Riccia is the simplest.
(2) Asexual (vegetative) reproduction in Liverworts takes place by fragmentation of thalli, or by the formation of specialised structures called gemmae (sing. gemma). Gemmae are green, multicellular, asexual buds, which develop in small receptacles called gemma cups located on the thalli. The gemmae become detached from the parental body and germinate to form new individuals. Eg. Marchantia
(3) During sexual reproduction male and female sex organs are produced either on same (eg. Riccia) or on different thallus (Eg. Marchantia)
ANTHOCEROTOPSIDA – HORNWORTS
(i) The plant body of this group is also thallus like. Scales are absent but rhizoids are present on thallus. Rhizoids are unicellular and unbranched.
(ii) The sporophyte of Hornworts is divided into foot and capsule.
(iii) The sporophyte of Hornworts is not completely depend on its gametophyte i.e. it is semiparasite because its sporophyte is photosynthetic therefore it can manufacture its own food. So it does not depend on gametophyte for food, it depends only for water and habitat.
(iv) In hornworts on the basal part of capsule, a special, type of meristem is present. Due to the activeness of this meristem, the capsule grows rapidly. It grows like the horn of animals.
eg. Notothylus, Anthoceros
BRYOPSIDA OR MUSCI – MOSSES (i) All the Mosses are included in this class. The plant body of mosses is made up of stem like, leaf like and rhizoids (roots like). The Rhizoids present in the plants of this class are multicellular, branched and obliquely septate.
Note – The presence of leaves in gametophyte is the unique character of Moss because in plant kingdom any gametophyte do not have leaves. They consists of upright selender axis bearing spirally arranged leaves.
(ii) Vegetative reproduction in mosses is by fragmentation and buding in the secondary protonema. During sexual reproduction, sex organs are produced at tha apex of the leafy shoots.
(iii) The sporophyte of moss in bryophyta is highly developed while the sporophyte of liverwort is the simplest. The sporophyte of moss is divided into foot, seta, capsule.
(iv) The sporophyte of mosses is also semiparasite like, that of Hornworts. i.e. it is photosynthetic. The moses have an elaborate mechanism of spore disperal.
Eg. of Mosses :
F u n a r i a - Rope moss or Cord moss
Polytrichum - Hair cap moss
D a w s o n i a - Australian moss - The highest bryophyte - 45 cm.
Page 62 www.selectialindia.com
B u x b a u m i a - Saprophytic moss - Photosynthesis absent.
S p h a g n u m - - Bog moss - It likes to grow on acidic bog.
Quaking bog
- Carpet moss or Turf moss & It spreads like a carpet on bog due to which, the swamp cannot be
easily seen.
- Peat moss & It is a fossil fuel that obtained from bog. The formation of peat takes place by the fossilization of Sphagnum. Sphagnum grows in acidic bog. The number of bacteria are less in bog due to which the degradation of dead cell could not takes place. Hence it is present in the form
of fossil.
- Absorbent cotton & Sphagnum can absorb water in very high amount, therefore it is used in the form of absorbent cotton in Europe.
– Bryophytes in general are of little economic importance but some mosses provide food for herbaceous mammals, birds and other animals. Species of Sphagnum, a moss, provide peat that have long been used as fuel, and because of their capacity to hold water as packing material for trans- shipment of living material. Mosses along with lichens are the first organisms to colonise rocks and hence, are of great ecological importance. They decompose rocks making the substrate suitable for the growth of higher plants. Since mosses form dense mats on the soil, they reduce the impact of falling rain and prevent soil erosion.
Page 63 www.selectialindia.com PTERIDOPHYTA Term pteridophyta was proposed by Haeckel The study of pteridophytes is known as pteridology. Pteridophytes are known as reptiles of plant kingdom.
1. Pteridophytes are also called as vascular cryptogames. Pteridophytes are vascular plants i.e. xylem and phloem are present in it. In pteridophytes, vessels in xylem and companion cells in phloem are absent. But exceptionaly xylem of Pteridium, Selaginella and Marsilea contains false vessels. Note :- Secondary growth is absent (due to absence of cambium) in pteridophytes but exceptionally secondary growth is present in stem of Isoetes. 2. Pteridophytes are used for medicinal purpose and as soil binders. They are also frequently grown as ornamentals. 3. Pteridophytes are called as the first successful terrestrial plants i.e. they are more adapted terrestrial plants as compared to bryophytes. Because - (i) Vascular tissue is present in pteridophytes. (ii) They have roots. 4. Pteridophytes are not completely successful terrestrial plants because they need water for fertilization, so pteridophytes grow in shady and moist places. 5. In pteridophyta, the plant body is completely differentiated in to root, stem and leaves.
The primary root remains alive for short period. After some time it is replaced by adventitious roots.
Stem is erect or prostrate. When in pteridophytes stem is underground, which is known as rhizome.
On the basis of leaves, pteridophytes are of two types - First in which stem is smaller while leaves are larger. They are known as macrophyllous Pteridophytes. eg. Pteridium, Pteris, Marsilea Second, in which stem is larger and leaves are smaller. They are called as microphyllous Pteridophytes. eg. Equisetum, Lycopodium, Selaginella
LIFE CYCLE OF PTERIDOPHYTES
1. Plant is sporophyte. i.e. diploid. 2. Most of the pteriophytes are homosporus i.e. only one type of spores are formed during reproduction. eg. Psilotum, Lycopodium, Equisetum, Pteridium, Dryopteris, Adiantum, Pteris. Exception - Some pteridophytes are heterosporus i.e. two types of spores microspores and megaspores. eg. Selaginella, Isoetes, Marsilea, Salvinia, Azolla, Stylites, Pillularia, Regnellidium 3. Formation of spores takes place in sporangia. Sporangia are formed at the abaxial surface of leaves. 4. The leaves on which sporangia are formed are called sporophylls (reproductive leaves) and normal photosynthetic leaves are called tropophylls (vegetative leaves). Sporangia are present in groups, these groups are called sorus (Plural-sori). Sori are found on sporophylls. Note : In pteridophyta, sporophylls are also photosynthetic. This is a unique character of pteridophyta. 5. Spore mother cells are present in sporangia. Spores are formed in these spore mother cells by meiosis and these spores start the gametophytic generation. Page 64 www.selectialindia.com 6. In pteridophyta, the germination of spores is exosporic i.e. germination takes place out side the sporangia (in soil) 7. In soil, a gametophyte is formed by the germination of each spore, which is known as prothallus. The formation of gametophyte takes place in the soil therefore it is free (independent) and mostly photosynthetic. These gametophyte require cool, damp, shady places to grow. Because of this specific restricted requirement and the need for water for fertilisation, the spread of living pteridophytes is limited and restticted to narrow geographical regions. 8. There is no relation between the main sporophytic plant and prothallus. Prothallus (gametophyte plant) is made up of thallus and rhizoids. It is non vascular. Note : In plant kingdom, gametophyte is always non vascular 9. In homosporus pteridophytes gametophyte is monoecious but in heterosporus pteridophytes the gametophyte is dioecious.
In heterosporus pteridophytes - Microspores form - Male gametophyte Megaspores form - Female gametophyte 10. The formation of sex organs takes place on this gametophyte. Male sex organs are called as antheridium and female sex organs are called as archegonium. The formation of male gametes takes place in Antheridia which are called as antherozoids. Antherozoids are spiral and multiflagellate but exceptionaly antherozoid of Selaginella are spindle shaped and in Lycopodium is curved (comma) and biflagellate. Egg is formed in archegonium.
11. Fertilization takes place by zoodiogamy and zygote is formed as a result of fertilization. Zygote develops and forms an embryo. Now this embryo develops and forms a sporophytic plant with root, stem, leaf.
Type of sexual repro duction in pteridophyta is oogamous.
Their life cycle is diplo-haplontic type.
The unique character of life cycle of Petridophyte is - Independent alternation of generation i.e. sporophyte and gametophyte are independent of each other.
Sporophyte (2n) Sporophylls Embryo Sporophytic (2n) (2n) generation Sporangia (2n) Zygote (2n) Spore mother cells (2n) Fertilization (Zoodiogamy) Gametophytic generation Meiosis Egg Antherozoids (n) (n) Spore (n) Antheridia (n) Gametophyte Archegonia or Prothallus (n) (n)
Page 65 www.selectialindia.com Pteridophyta is divided in to 4 classes
1. Psilopsida 2. Lycopsida 3. Sphenopsida 4. Pteropsida
1 . Psilopsida :
The most ancient vascular plants are placed in this class. The plants in this class have many primitive characters -
(i) Their plant body is differentiated in to stem (rhizome), scaly leaves and rhizoids.
Only one living genus is present in this class - Psilotum A living fossil
Rhynia and Horneophyton – Fossil plants
2 . Lycopsida :
(i) Club mosses are placed in this class.
(ii) The plant body of club mosses is differentiated into root, stem and leaves. Leaves are green and photosynthetic and known as tropophylls.
(iii) Sporophylls are present in group at the tip of plant. This groups is called as strobilus or cone.
L y c o p o d i u m - Common club moss or Ground pine or Trailing evergreen
It is a medicinal plant. It is used as tonic in Homeopathic medicines.
Selaginella - Little club moss or spike moss or Bird's nest moss or Resurrection plant.
Selaginella bryopteris -It is known as "Sanjeevani"
3 . Sphenopsida
(i) In this class Horse tails are included.
(ii) The plant body of horse tails are differentiated into root, stem or rhizome & scaly leaves.
(iii) Silica is present in the epidermis of stem and leaves. Due to silicated surface, leaves become rough. If two horse tail plants collide, then there is a dangerous chance of fire in the forest.
(iv) The formation of sporangia takes place on special branches of stem called as sporangiophores. Sporangiophores are arranged in a group and form a long and condensed cone. This cone is formed at the apical part of aerial stem.
e.g. Equisetum (Pipe)
4 . Pteropsida :
(i) This is the largest group of pteridophytes.
(ii) They are commonly called as ferns. Most of the pteridophytes are ferns.
(iii) Ferns are megaphyllous (macrophyllous) i.e. rhizome is small and leaves are compartively larger and these leaves are known as 'Fronds'.
(iv) Multicellular hair are present on the young leaf and young rhizome of ferns which are called as ramenta. They are for protection.
(v) There is no difference between tropophylls and sporophylls in fern i.e. every leaf of fern forms sporangia at the time of reproduction. Therefore cones are not produced in ferns.
Page 66 www.selectialindia.com Examples of Ferns : P t e r i d i u m - They are called "Braken fern" or "Sun fern" D ry o pt e ri s - Also called as Brook shield fern' A d i a n t u m - Walking fern This name is given to them due to rapid vegetative reproduction. Vegetative reproduction in Adiantum takes place by means of leaf tip. It spreads very fast. O s m u n d a - Royal fern or flowering fern Ophioglossum - Adder's tongue fern M a r s i l e a - Pepper wort fern A z o l l a - Aquatic fern (Smallest pteridophyte and biofertilizer) A l s o p h i l a - Tree fern (Largest pteridophyte) P t er i s - Salv inia -
SOME IMPORTANT POINTS :-
( 1 ) Selaginella and Salvinia * In heterosporus pteridophyts Selaginella and Salvinia the female
gametophytes are retained on the parent sporophyte for variable periods.
* The development of the zygote in to young embryos takes place with in the female gametophyte. Genera like Selaginella and Salvinia possess partially endosporic development of embryo.
* This event is a precursor of seed habit considered an important step in evolution.
( 2 ) Selaginella * Ligulate leaves (tongue shaped) are present in it
Function - Ligule is secretory structure, which secretes water and keeps the sporangium and the young leaf moist.
( 3 ) In some pteridophytes sporangia are not formed on lower surface of sporophylls -
* In some pteridophytes sporangia are formed at the axil of leaf.
e g . Selaginella
* In some pteridophytes sporangia are formed in spike.
e g . Ophioglossum
* In some pteridophytes sporangia are formed in sporocarp.
e g . Marsilea, Azolla, Salvinia
( 4 ) In some pteridophytes prothallus is saprophytic and the heterosporus pteridophytes like Selaginella and Salvinia gametophytes are not called prothallus.
Page 67 www.selectialindia.com GYMNOSPERM
1 . The gymnosperms (gymnos = naked, sperma = seed) and plants in which the ovule are not encloded by any
ovary wall and remain exposed, both before and after fertilization.
2 . Study of Gymnosperm known as Gymnospermology.
l Main plant body of Gymnosperm is divided in to Root, Stem and leaves.
l The roots are generally tap roots.
Note : - Roots in some genera have fungal association in the from of mycorrhiza (Pinus), while in some
others (Cycas) small speciallised roots called coralloid roots are associated with N2-fixing cyanobacteria.
l The stems are unbranched (Cycas) or branched (Pinus, Cedrus).
l The leaves may be simple or compound.
l In Cycas the pinnate leaves persist for a few years.
l The leaves in gymnosperms are well-adapted to extreme condition.
l In conifers the needle like leaves reduce the surface area, their thick cuticle and sunken stomata also help
to reduce water loss.
3 . Gymnosperm & Angiosperm are collectively included under spermatophyta i.e. seed bearing plants.
4 . Gymnosperms are naked seeded plant i.e. no fruit formation takes place in these plant.
i.e. in gymnosperm embryo & seed formation takes place but no fruit formation occur.
5 . Gymnosperms are very limited in distribution. They are mainly found in cold regions.In India Gymnosperms are found on Himaliayan mountains. They occur on slopes of mountain in cold region therefore gymnosperms are
xerophyte.
6 . All gymnosperm are vascular plants. Therefore vascular tissue present i.e. xylem & phloem. Xylem lack vessels
& phloem lacks companion cells.
Note :-
l Exceptionally in xylem of Gnetum, Ephedra, Welwitschia true vessels are present.
l Secondary growth takes place in gymnosperms stem, so Gymnosperms stem is woody.
7 . Most of the gymnosperms are arborescent (woody and tree habit) - but some are present as shrub.
e g . E p h e d r a
Some Gymnosperm are liana or woody climbers. e g . Gnetum ula Page 68 www.selectialindia.com LIFE CYCLE OF GYMNOSPERM -
1. In Gymnosperms main plant body is sporophyte (diploid). All Gymnosperm are dioecious. i.e. male & female plants are separate, but exceptionally Pinus is monoecious.
2. All Gymnosperms are heterosporus. At the time of reproduction two types of spores are formed.
l Microspores form – Male gametophyte
l Megaspores form – Female gametophyte
3. These two types of spores are formed in different sporangia.
l Microspores are formed in Microsporangia.
l Megaspores are formed in Megasporangia. Integumented megasporangia are also termed as ovule.
4. Both types of sporangia are formed on different sporophylls.
l Microsporangia are formed on Microsporophyll.
l Megasporangia are formed on Megasporophylls.
5. Both types of sporophylls are found in groups & form male cone (strobilus / Microsporangiate) & female
cone(Macrosporangiate).
6. Meiosis takes place in cells of microsporangium & megasporangium and form microspore & megaspore
respectively.
7. In Gymnosperm and angiosperm germination of spores is endosporic i.e. germination of spore takes place
with in sporangia.
8. Male gametophyte is formed after germination of microspore. Male gametophyte is also known as pollen grain.
Male gametophyte forms male gamete.
9. In lower gymnosperm, male gametes are motile & multiciliate, but in higher gymnosperm and angiosperm male gametes are non motile due to the absence of cilia and flagella. They do not require water for fertilization.
l Main body of ovule is made of a diploid tissue called as nucellus.
l A cell of nucellus acts as megaspore mother cell which undergoes meiosis and forms four haploid megaspores, out of which only one remains functional and rest three degenerate.
l This megaspore further develops into female gemetophyte or endosperm.
l The cells of female gametophyte or endosperm behave like arcegonial intials and form two or more
archegonia.
l Archegonia - It forms egg.
Page 69 www.selectialindia.com
(Ovule) Integument (Ovule)
Nucellus
(Endosperm)
(F)
Micropyle
Endosperm (Female Gametophyte)
(G) (H)
10. Pollen grains (Male gametophyte) reach at the micropyle of ovule by wind, called as anemophilly. After pollination male gametophyte (pollen grains) are stored in the pollen chamber of ovule.
FERTILIZATION &
Two types of fertilization take place in gymnosperms
( 1 ) Zoodio - siphonogamy & This type of fertilization occurs in lower gymnosperms. Male gametes are motile and transfered to female gamate by pollen tube. (2) Siphonogamy & This type of fertilization occur in higher gymnosperms. Male gametes are non motile transferred to female gamete (egg) by pollen tube. After Pollination male & female gametes are fused & form a diploid zygote.
l In gymnosperm single fertilization takes place so only zygote is formed through fertilization. In Angiosperm double fertilization takes places so two product are formed after it (i) Zygote (ii) Endosperm.
l In gymnosperm, endosperm is formed before fertilization by megaspore so it is haploid but in angiosperm endosperm is formed after fertilization by triple fusion (sec. nucleus (2n) + male gamete (n). So, endosperm of angiosperm is triploid.
l In angiosperm, fertilization take place by siphonogamy. Gymnosperm + Angiosperm = Siphonogama Page 70 www.selectialindia.com
Sporophyte (2n) Sporophyte (2n)
Male cone (2n) Female cone (2n) D i p l o i d
Microsporophylls (2n) Megasporophylls (2n)
Microsporangium (2n) Megasporangium (Ovule) (2n) Meiosis in microspore mother cells Meiosis in megaspore mother cell Microspores (n) Megaspores (n) Germination Germination Male gametophyte (Pollen grain) (n) Female gametophyte (n) (Endosperm)
H a p l o i d Male gametes (n) Archegonia (n)
Female gamete (egg) (n)
Fertilization By Zoodio–siphonogamy OR Siphonogamy
Zygote (2n) Mitosis D i p l o i d Embryo (2n)
Seed
Sporophyte (2n)
LIFE CYCLE OF GYMNOSPERM
Page 71 www.selectialindia.com DEVELOPMENT OF ZYGOTE –
1. Embryo is formed by the development of diploid zygote. After embryo formation ovule is changed into seed.
l Embryo enclosed in ovule because development of spore is endosporic.
l Seeds are not formed in pteridophyta because germination of spore is exosporic i.e. embryo develops outside the sporangia. 2. Embryo is enclosed in seed. Seed absorbs water & bursts. Now embryo germinates and forms a new diploid plant. Note :- Different types of polyembryony are found in gymnosperm i.e. in single seed more than one embryos are produced.
LIFE CYCLE : Life cycle of Gymnosperm & angiosperm is diplontic because gametophytic generation is short lived. Gametophyte is very reduced & depends on its sporophyte.
SOME IMPORTANT POINTS :
1. Antheridia is absent in gymnosperm & angiosperm i.e. pteridophyte is last group having antheridia. But archegonia is also absent in angiosperm. So gymnosperm is last group having archegonia.
2. During evolution Gametophyte becomes reduced & sporophyte becomes well-developed.
Very reduced – In Angiosperm Gametophyte Well developed – In Moss
Very reduced – In Thallophyta (Only zygote) Sporophyte Well developed – In Angiosperm
Gymnosperms are divided into two groups
(1) Cycadophyta (Lower Gymnosperm) (2) Coniferophyta (Higher Gymnosperm)
CYCADOPHYTA
(A) The plants of this group are megaphyllous or macrophyllous with circinate vernation.
(B) Presence of Ramenta.
(C) Male gamete is motile.
Cycadophyta is divided into three orders (i) Cycadofillicales or Pteridospermae :- This order is completely extinct. Plant of this order known as seed fern. eg. Lyginopteris - Fossil plant (ii) Benettitales :- (a) It is also a completely extinct group.
eg. Williamsonia - fossil plant Note : Its fossils were discovered by Prof. Birbal Sahani
Page 72 www.selectialindia.com (iii) Cycadales - (a) Presently living cycadophytes are included in this order.
(b) All the plants of this group are living fossils.
Zamia pygmea - Smallest Gymnosperm
C yc a s - Fern palm or Sago palm
Sago is obtained from its stem.
The diameter of its ovules is 7 cm. Its ovule, male gametes, egg and male cone are largest in plant kingdom. In embryo of cycas two cotylesons are present. In cycas male gamates are top shaped. In Cycas female cone is absent.
CONIFEROPHYTA
Four orders are included in this group (i) Ginkgoales :- (a) It is the oldest order of coniferophyta. Maximum plants of this group are extinct. Ginkgo biloba - living fossil - It is also known as "Maiden hair tree". Note : Exceptionally Ginkgo biloba belongs to higher gymnosperm but its male gametes are motile. (ii) Cordaitales :- (a) It is completely extinct group
eg. Cordaites (iii) Coniferales :- (a) Conifers are included in this group. (b) It is the largest group of gymnosperm
Examples of Coniferales - ( a ) Pinus (Pines) :- Pinus species – A resin "turpentine" is obtained from it. Turpentine is used in varnish.
Pinus gerardiana – It is known as "chilgoza pine"
Pinus roxburghii – It is known as "chirpine".
(b ) C e d r u s – It is known as deodar. (c ) Ta x u s – It is known as Yew tree. An anticancer medicine "Taxol" is obtained from its bark.
(d ) Taxodium maxicanus – The stem of this plant is thickest in the plant kingdom. (e) Abies balsamea – A resin "Canada balsam" is obtained from it. It is used to manufacture permanent slides in biology laboratory. (f ) Juniperus virginiana – An oil is obtained from this tree - "Cedar wood oil". It is used as cleansing fluid in biology laboratory. This oil is also used in microscope to increase the resolving power. This oil is used as nail polish remover.
Page 73 www.selectialindia.com (g ) Araucaria species Araucaria excelsa – Christmas tree Ornamental plants Araucaria araucana – Monkey puzzle tree (h) Sequoia species – The plants in this genus are heavy. Therefore they are called as father of forest. Sequoia giganteum – It is called Red wood tree or Sherman tree. It is the largest gymnosperm. There is only one tree of this species and that is in California (America) (i) Metasequoia – It is a living fossil. This plant is present in china valley.
(iv) Gnetales -
(a) They are the most advanced gymnosperms.
(b) Exceptionally members of this group have vessels in xylem.
(c) Archegonia is absent in the members of this group.
e g . (1) Gnetum (2) Welwitschia
(3) Ephedra – Exceptionally archegonia is present in Ephedra.
E p h e d r a - This gymnosperm is commonly found in Rajasthan. Ephedra is a medicinal plant. Ephedrine (Medicine) is obtained from it. It is an effective medicine in asthma. Athletes misuse it, so ephedrine is restricted for them.
Cycadofillicales were first seeded plants. First time seed habit was established in this group. In general way seed habit was originated from those pteridophytes which are now extinct. These pteridophytes were ancestor of cycadofillicales.
Some heterospones pteridophyes Selaginella and Salvinia show origin of seed habit.
There is mainly two requirements for seed formation
(1) Plant should be heterosporus (2) Germination of megaspore should be endosporic
Page 74 www.selectialindia.com HISTORY OF TAXONOMY 1 . Moreover, the biologists considerebly depend on taxonomic studies of fossils connecting links for drawing evolutionary relationships among the organisms. 2 . Linnaeus : - Carl Von Linne was born in Sweden. As a child, he developed an interest in plants. On persuasion he joined the medical school, though his parents wanted him to be a minister. Medical course being closely related to plants then, Linne continued with the collection, study and description of plants. After completing medical degree in 1739, he went to Holland and became the personal physician of a wealthy government official. There he also studied and described all the plants of his employer's garden. At the age of 22, he published his first paper on sexuality of plants. Later he published 14 treaties and also brought out famous Systema Naturae from which all fundamental taxonomical researches emanated. His system of classification was a simple scheme for arranging plants for identifying them again. Linne with his lectures and publications in Latin become Carolus Linnaeus. 3 . De Jussieu brothers – Antoine, Bernard and Joseph - France : Book of De Jussieu brother is "Genera Plantarum Secundum Ordines Naturals Disposita". De Jussieu brother proposed the first complete natural classification of plant kingdom. They classified plant kingdom in three groups - 1. Acotyledonae 2. Monocotyledonae 3. Dicotyledonae Note : De Jussieu brothers employed the characters of embryo in taxonomy propose the significance of vascular tissue in taxonomy. 4 . Hutchinson (1926), England : Hutchinson was also related with Royal Botanical Garden. Hutchinson proposed phylogenetic classification of flowering plants. In his book "The families of flowering plants", he described 411 families of flowering plants. Hutchinson for the first time stated that monocots are more advance than the dicots. 5 . Takhtajan, 1966 (Russia) : In his book "Flowering plants - Origin and dispersal", he proposed new names to some plants groups - Angiosperms = Magnoliophyta Dicots = Magnoliatae Monocots = Liliatae There is one famous statement of Takhtajan about the importance of Phylogeny in taxonomy- "Taxonomy without phylogeny is like bones without flesh". 6 . Haeckel proposed three kingdom classification and copeland proposed four kingdom classification. 7 . John Lindley - England : First distinguished the Cryptogams and Phanerogams. The name cryptogames was first used by Linnaeus and the name phanerogams was first used by Theophrastus. 8 . • Adolf Engler and Karl Prantl gave a phylogenetic system in their book "Die Naturalichen pflanzen families". • They classified flowering plants on the basis of floral morphology, like characters of petals, perianth etc. • According to them monocots are more primitive than dicots which is actually not correct according to phylogeny. 9 . Ernst Mayr (1904-2004) : • Ernst Mayr was a Evolutionary biology biologyst who has been called. "The Darwin of the 20th century". • He studied various field of biology like oonithology, taxonomy, zoogeography, evolution, systematics and the history and philosophy of biology, so he is also assumed the title "Alexander Agassiz professor of zoology emeritus." • Mayr was awarded the three prizes biology called as triple crown, they are Balazen prize, International prize and the crafoord prize. Page 75 www.selectialindia.com SOME SPECIAL POINTS
1 . (i) Cladogram : Family tree (line diagram) representing evolutionary relationship (Ancestory of evolution) of organisms. (ii) Dendrogram : Family tree based on numerical taxonomy. 2 . Based on the structure of plant body and the method of sexual reproduction, bryophytes are divided into three classes-Hepaticae (Hepaticopsida), Anthocerotae (Anthoceropoida) and Musci (Bryopsida). 3 . The Pteriophyta is divided into four classes, viz. Psilopsida, Lycopsida, Sphenopsida and Pteropsida, on the basis of organisation of plant body including the nature of leaf, vascular system, and location of sporangia. A typical pteriodphyte as represented by fern has a plant body differentiated into distinct underground stem like rhizome, bearing roots, and aerial shoot with leaves. It helps the plant to regenerate if the aerial parts are destroyed by fire or animals. The pteridophytes have primitive vascular system. Adiantum, yet another well- known fern shows a characteristic mode of multiplication. Whenever its leaf tip comes in contact with soil it develops adventitious roots and forms a new plant. as such it is also called the walking fern. You might have observed a similar mechanism of vegetative propagation through runners and suckers. The leaves are of two types. Some ferns have simple leaves with a single vein whereas the others have compound leaves, comprising several leaflets (pinnules) like the flowering plants. The compound leaves in Adiantum with black shining petiole are beautifully arranged to provide appearance of a maiden's hair. hence it is also given the name maiden hair fern. 4 . Gymnosperms are divided into three classes-Cycadopsida, Coniferopsida and Gnetopsida on the basis of nature of leaves, wood, vascular system and reproductive structures. SOME INFORM ATIONS RELATED TO BIOTECHNOLOGY WITH RESPECT TO BACTERIA AND FUNGI– 1. Different varieties of cheese are known by their characteristic texture, flavour and taste, the specificity coming from the microbes used. For example, the large holes in swiss cheese are due to production of a large amount
of CO2 by a bacterium named Propionibacterium sharmanii. 2. "Toddy" a traditional drink of some parts of southern India is made by fermenting sap from plams with the help of microbes. 3. Streptokinase produced by the bacterium Sterptococcus and modified by genetic engineering is used as a clot buster for removing clots from the blood vessels of patients. 4. Cyclosprin A, that is used as an immunosuppressive agent in organ-transplant patients is produced by the funges Trichoderma polysporum. Statins produced by the yeast Monascus purpureus have been commercialised as blood-cholestrol lowering agent. BOTANICAL GARDENS, HERBARIA AND RESEARCH INSTITUTE (1) Oldest botanical garden is "Padua Botanical Garden" Italy (Established -1545). (2) Largest Botanical garden in the world is Royal Botanical Garden, Kew, Surrey, England, established by William Aiton, 1759. (3) Largest herbarium of the world is ‘‘Museum of Natural History’’ – Paris – with a collection of 8880000 specimens. (4) Largest Botanical Garden of Asia is Indian Botanical Garden, Sibpur, Kolkota. Established by Robert Kyd, 1786.
* Largest herbarium of Asia is Central National Herbarium located in Indian Botanical Garden, with a collection of 25 lakh specimens.
* Indian Botanical Garden is famous due to the presence of "Great Banyan Tree" in its campus.
Page 76 www.selectialindia.com * In campus of Indian Botanical Garden Botanical Survey of India (BSI) is present which is established by William Rouxburgh 1890. * BSI Botanical Survey in India is done by BSI (5) National Botanical Garden, Lucknow. National Botanical Research Institute (NBRI) is located in National Botanical Garden. (6) Forest Botanical Garden, Dehradun - Forest Research Institute (FRI)is located in Forest Botanical Garden. (7) Lloyd Botanical Garden – Darjeeling. (8) CDRI - Central Drug Research Institute - Lucknow (9) CAZRI - Central Arid Zone Reserch Institute - Jodhpur (10) CIMAP - Central Institute of Medicinal and Aromatic Plants - Lucknow (11) IARI - Indian Agriculture Research Inst. (Pusa Inst.) - New Delhi (12) Birbal Sahni Institute of Paleobotany (National inst. of paleobotany) - Lucknow
CLASSES OF ALGAE AND THEIR MAIN CHARACTERISTICS
C la s s e s Com mon M a j o r Sto red Cell Wall Flag e llar Ha bi ta t N am e Pig ments Food Number and Position of Ins ertions
Chlorophyceae Green Chlorophyll Starch Cellulose 2-8, equal, Fresh water algae a,b apical brackish water, salt water
Phaeophyceae Brown Chlorophyll Mannitol, Cellulose 2,unequal, Fresh water algae a,c, laminarin and algin lateral (rare) brack fucoxanthin -ish water, salt water
Rhodophyceae Red Chlorophyll Floridean Cellulose Absent Fresh water algae a,d, phyco- starch (some), erythrin brackish water, salt water(most)
Name of Algal cell Shape of Chloroplast
l C h a r a Discoid
l Fritschiella Plate like
l Chalamydomonas Cup-shaped
l U lo t h ri x Girdle shaped
l Sp ir og yr a Ribbon / Spiral shaped
l Z y g n e m a Stellase
l O e d o g o n i u m Reticulate
Page 77 www.selectialindia.com ORGANISMS WITH THEIR TA XONOMIC CATEGORIES
Com mon Biolog ic al Genus Family O rd e r C l a s s Phy lum N am e N am e Divis ion
Man Homo Homo Hominidae Primata Mammalia Chordata Sapiens
Housefly M u s c a Musca Muscidae Diptera Insecta Arthropoda domestica
Mango Mangifera Mangifera Anacardiaceae Sapindales Dicotyledonae Angiospermae
Wheat Triticum Triticum Poaceae Poales Monocotyledonae Angiospermae aestivum
CHARACTERISTICS OF THE FIVE KINGDOMS
Five Kingdoms Ch ara c te rs Mon era Pr ot is ta Fung i Plan tae Anim alia
Cell type Prokaryotic Eukaryotic Eukaryotic Eukaryotic Eukaryotic
Cell wall Noncellulosic Present in Present Present Absent (Polysaccharide some (without cellulose) (cellulose) + amino acid
Nuclear Absent Present Present Present Present membrane
Body Cellular Cellular Multiceullar/ Tissue / Tissue / organ / organisation loose tissue organ organ system
Mode of Autotrophic Autotrophic Heterotrophic Autotrophic Heterotrophic nutrition (chemosynthetic (Photosynthe- (Saprophytic/ (Photosynthet- (Holozoic / and photosynth- tic) and Hetero- Parasitic) tic) Saprophytic etc.) etic) and Hetero- trophic trophic (sapro- phytic / para- sitic)
Page 78