Overview
👉The plant kingdom is divided into two groups: Cryptogams and phanerogamae.
👉Cryptogams are those that are reproduced by means of spores. They do not produce any type of seed. The algae and fungi are kept under cryptogams along with the bryophytes and pteridophytes.
👉The pteridophytes are used in medicine and prevent soil erosion by acting as a soil binders. They are also used as ornamental plant. They are first terrestrial plant having vascular tissue like xylem and phloem.
👉The pteridophytes are vascular cryptogams as they have a well developed conducting system of tissue.
Vascular cryptogams are seedless vascular plants that have successfully invaded the land.
🔵Extra shot of Pteridophytes
The Pteridophytes appeared on earth around 280 to 250 million years ago. They grow in a variety of habitats which are mostly terrestrial. They grow well in abundant moisture conditions and shade areas but some like Selaginella lepidophylla,
Gleichenia can grow well in xerophytic or sandy soil conditions. In addition to this, few are found in aquatic conditions like Marsilea, Salvinia, Azolla.
Some Members are grown as epiphytes such as Selaginella oregana, Lycopodium phlegmaria. Some Pteridophytes are also exist as fossil like Rhynia, Hornea, Zosterophyllum.
🌑General feature of Pteridophytes
🌑Sporophyte
🔴 Sporophyte is the dominant phase in pteridophytes. Sporophyte is divided into root stem and leaves.
🔴All plant organ like Root, stem leaves possess vascular tissue like xylem and phloem. Pteridophytes are the first true land plants that successfully grow in land.
🔴Pteridophytes are seedless, vascular cryptogams. Stem is usually branched but branches do not arise in the axil of the leaves. In many Pteridophytes, the stem is represented by a rhizome. Roots are adventitious in nature.
🔴Leaves may be small and thin termed as microphyll like Equisetum and Selaginella. In Fern Dryopteris, Adiantum, leaves are large and pinnately called macrophyll. Young leaves of sporophyte show circinate vernation.
🌑Sporangia
🔴The leaves of pteridophytes bearing the sporangia are termed as sporophylls. Spores are produced in sporangia through meiosis. Spores are homosporous or heterosporous.
🔴The spores that are formed of similar size and one type are termed as homosporous whereas in heterosporous conditions, two kinds of spores are produced.
🔴Sporangia are produced in groups on sporophylls. Sporangia may be borne either on stem or leaves.
🔴On leaves, sporophyll are located marginally like Pteris, Adiantum. On the stem they are located terminally like Rhynia and in Lycopodium they are found at lateral position.
🌑Prothallus formation
🔴In Equisetum and selaginella the sporangia are borne on special structures called sporangiophores. Such sporangia is called cone or strobli.
🔴In Marsilea, Azolla, Salvinia sporangia are produced in sporocarps. Sporangia produce spores by meiosis from the spore mother cell.
🔴These spores on germination give rise to inconspicuous, small multicellular and free living, thalloid gametophytic bodies called Prothallus.
🔴In homosporous Pteridophytes prothallus are monoecious or antheridia and archegonia develop on the same prothallus.
🔴In heterosporous species, prothalli are always dioecious. Microspores on germination give rise to male prothallus and megaspores gives rise to the female prothallus.
🌑Gametophyte
🔴As described earlier, Antheridia and archegonia are developed on prothallus or Gametophyte.
🔴Antheridium is surrounded by sterile jackets. Fertilization results in the formation of zygote which ultimately develops into a well-developed sporophyte.
🔴Plants show alternation of generation like bryophytes. but in pteridophytes,the main plant body is sporophytic. and forms a dominant phase in the life cycle.
🌑Reproduction
🔴Gametophyte stages bear Antheridia and Archegonia in the form of male and female gametes. Antheridia produce male gametes called antherozoids.
🔴These Antherozoids are moved by using water as a medium at the mouth of Archegonium.
🔴In archegonium there is an egg that fuses with the male gamete and forms zygote. Later on, zygote produces a multicellular sporophyte, a dominant phase of pteridophyte.
🌑Precursor Seed habit in Pteridophytes.
🔴In selaginella and salvinia, two kinds of spores are produced in sporophyte: one is large and the other is small. 🔴These spores are termed as megaspore and microspore. The megaspore and microspore give rise to female and male gametophytes.
🔴In female Gametophyte, zygote is developed into embryo but it remains attached with sporophyte. This attachment of gametophyte with embryo to sporophyte is regarded as precursor of seed habit in plant .
🌑Stelar system
🔴The special arrangement of xylem and phloem in vascular bundle with or without pith along with cortex is called stele. 🔴Pteridophytes have well developed stele and well diversified stelar system .
1. Pteridophytes are used as:
A. Ornamental plants
B. Soil binders
C. Medicinal plant
D. All of the above
Answer : C
2. Consider the following statement and select the correct code:
1. Most of the Pteridophyte es are found in cool, damp and Shady places.
2. Some of the pteridophytes are found in sandy soil condition.
A. Only 1 B. Only 2
C. Both 1 and 2
D. Neither 1 nor 2
Answer: C
3. How many statements is/ are correct.
1. Evolutionary, Pteridophytes are first land plants having vascular tissue like xylem and phloem.
2. Main plant body of Pteridophytes is Sporophyte.
3. Sporophyte is Differentiated into Root, Stem and leaves.
4. Vascular tissue are present in root and stem but not present in leaves
A. One B. Two
C. Three D. Four
Answer : C
4. Which of the following statement is not statement.
A. Microphylls are small leaves in Pteridophytes born on sporophyte.
B. Macrophylls are large leaves of Pteridophytes born on sporophyte.
C. Sporangia which produce spores born on sporophylls.
D. The sporangia produce spore by mitosis in spore mother cell.
Answer : D
5. In which genera of Pteridophytes, sporophylls form compact mass called Strobli or cones.
A.Selaginella & Equisetum
B.Lycopodium&
Selaginella
C. Adiantum and Dryopteris
D. Adiantum and Lycopodium
Answer : A
6. Match the List
A.Microphyll 1.Seleginella
B.Macrophyll 2. Fern
C. Strobli 3. Equistem
A B C
A. 1 2 3
B. 3 2 1
C. 3 1 2
D. 1 3 2
Answer : A
6. In pteridophyte, Spores formed in sporangia give rise to a inconspicuous and small gametophyte called
A. Protonema
B. Gemmae
C. Prothallus
D. Leafy stage
Answer: C
7. Which of the following statement is not correct about the gametophyte of Pteridophytes ( Prothallus)
A. Living Pteridophytes are restricted to narrow geographical region because they require water for fertilization.
B. Prothallus or gametophyte are developed from the spores produced in sporangia on sporophyll.
C. Gametophyte bear male and female sex organ in form of Anthredia and Archegonis respectively.
D. Wind is required for transfer of Antherozoids to mouth of archegonium and fuse with egg to form zygote.
Answer : D
8. Consider the following statement and select the correct code:
1. Most of the pteridophytes are homosporous because they produce similar kind of spores in sporangia.
2. Homosporous pteridophytes give rise to Prothallus or gametophyte which have both male and female sex organ.
3. Anthredia transfer antherozoids through the water and form zygote by fusion with egg of Archegonium.
4. Zygote give rise to well differentiated multicellular sporophyte.
A. 1 ,2 and 3 B. 2, 3 and 4
C. 1, 3 and 4 D.1,2,3 and 4
Answer: D
9. Consider the following feature of Prothallus of Pteridophytes and select the correct code:
1. Multicellular
2. Unicellular
3. Free living
4. Mostly Photosynthetic
5. Thallus
6. Filamentous
A. 1, 3, 4 and 5
B. 2, 3, 4 and 5
C. 2, 3 , 4 and 6
D. 1, 3 , 4 and 6
Answer : D
10. Heterospory or heterosporous condition are found in
A. Selaginella
B. Salvinia
C. Both selaginella and Salvinia
D. Selaginella, Salvinia and Lycopodium
Answer : C
11. Consider the following statement and select the correct code:
1. In homosporous Pteridophytes, male and female reproductive organs are found in same prothallus.
2. In heterosporous Pteridophytes, male Prothallus and female prothallus are different.
A. Only 1 B. Only 2
C. Both 1 and 2
D. Neither 1 nor 2
Answer: C
12. Consider the following statement about the heterospory condition of pteridophyte and select the correct code:
1. Plant produce two different types of spores on sporophyll.
2. These spores are micro and megaspore which give rise to male and female gametophyte ( prothallus) respectively.
3. In heterosporous condition, the female gametophyte are remain present on parent sporophyte for some periods.
A. 1 and 2 B. 2 and 3
C. 1 and 3 D. 1 2 and 3
Answer: D
13. Which of the following statement is not correct about the Pteriodophytes.
A.Most of gametophyte is photosynthetic.
B. Most of the sporophyte is photosynthetic.
C. Heterosporous Pteridophyte give rise to Diocious Gametophyte.
D. Both gametophyte and sporophyte are multicellular.
Answer: B
13. Which one the following event in Pteridophytes is precursor of seed habit and is important step of Evolution.
A. The Pteridophytes are found in limited and narrow range of geographical because they need water for fertilisation.
B. In selaginella and Salvinia, Micro and mega spores give rise to Male and female gametophyte.
C. Both gametophyte and sporophyte are photosynthetic and no any stage is depend on one another for nutrition.
D. The female gametophyte is remain present on parent sporophyte and development of embryo from zygote takes place female gametophyte.
Answer : D
14. Match the list with Class of Pteridophyte and their Example.
A. Psilotum 1. Psilposida
B. Selaginella 2.Lycopsida
C. Pteropsida 3. Adiantum
D.Sphenopsida4. Equistem
A B C D
A. 1 2 3 4
B. 4 3 1 2
C. 1 3 2 4
D. 4 1 3 4
Answer : A
15. Dryopteris and Pteris both belong to which Class of pteridophytes.
A.Psilotum
B. Lycopsida
C. Sphenopsida
D. Pteropsida
Answer: D
16. Identify the given diagram
B. Lycopodium
C. Salvinia
D.Dryopteris
Answer : C
17. Pteridophytes includes
A. Moss and Fern
B.Liverworts and Horsetail
C. Hornworts and Horsetail
D. Horse tail and Fern
Answer: D
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