Pteridophytes
All living beings on the planet are classified into five different kingdoms. They are kingdom monera, kingdom Protista, kingdom fungi, kingdom Plantaeplantae and kingdom Animalia. Classification and nomenclature were adopted by specialists in the field to make the process of understanding the living world more convenient. All biotic elements fall into one of these categories based on whether they are unicellular or multicellular, whether they reproduce through a particular method, whether they have or not have a cell wall etc.
Kingdom Plantae is an important kingdom in the living world. It encompasses five categories, namely thallophyta, Bryophyta, Pteridophyta, gymnosperms and angiosperms. They are eukaryotic and often multicellular. They adopt various methods for reproduction like fragmentation, budding and sexual reproduction. Plant species are classified into these five categories based on so many criteria like their mode of reproduction etc. But these distinctions are not always rigid and sometimes certain species can occupy the border positions until the problem is solved by specialists on taxonomy and nomenclature.
Pteridophytes are the third category in this classification. They are less sophisticated than gymnosperms and angiosperms but have a more complex body structure than thallophytes and bryophytes. This is because they are vascular and reproduce through spores. This sophisticated body organization of the thallophytes has evolved over centuries on the planet. The same trend is observed in nearly all the kingdoms where evolution takes place gradually. For convenience, specialists have arranged kingdoms and subgroups in the taxonomy according to the level of evolution each plant or animal species has undergone through the years.
What are Pteridophytes?
The pteridophyte is derived from two words; Pteron, meaning feather in Greek, and python means herb. So, this name was originally given to those plant groups that had well-shaped feather-like leaves. These plants carry no flowers or seeds. Therefore, they are also called Cryptogams, simply because their means of reproduction are secret. A cryptogam, Cryptogamae scientifically is a plant (in the broad sense of the word) that reproduces by spores, without flowers or seeds.
"Cryptogamae'' is taken from Greek, that is, Kryptos meaning "hidden" + game meaning "to marry." The hidden reproduction refers to the fact that cryptogams represent the non-seed-bearing plants without the production of seeds. We are in reality the first developed group of plants with a vascular tissue network for water and food transport. They're found mostly in dark, damp areas. They include horsetails and ferns. The ferns are mostly used as ornamental plants.
Importance of MCQs
This set of Multiple - Choice Questions & Answers (MCQs) focuses on "pteridophytes." These questions are short and sharp that cover the whole topic and let students assess their knowledge on a given topic.
NCERT often focuses on extensive learning of topics due to which the syllabus covers a vast range of topics to better prepare the students. In such a scenario, an easy method for students to remember the important topics is by solving MCQs whenever they can. In this manner, students will be able to go through a lot of topics in a short time. This will be convenient for students during their exam preparation. MCQs cover all important topics of any specific unit and can be used by students to evaluate if they have properly gone through any chapter.
Time and memory are two important factors in life for every student and this problem is efficiently solved with the help of MCQs. Revision using MCQs is very productive in learning and should be made an inevitable part of any curriculum. Vedantu’s MCQs on pteridophytes similarly solve the problem of time for students since they are crisp, to-the-point and easy to comprehend.
Solved Multiple-Choice Questions
1. Which of These is a Member of Vascular Cryptogams?
Bryophyta
Pteridophyta
Gymnosperms
Angiosperms
Solution: B
2. Sporangium is Produced From………………. In Eusporangiate Ferns?
A single, superficial sporangial initial
A group of sporangial initial cells
Vegetative shoots
Root mass
Solution: B
3. Select below Which has Vascular Tissue and Produces Spores, but does not Contain Seeds?
Bryophyta
Pteridophyta
Gymnosperms
Angiosperms
Solution: B
4. In ferns, Leaves During Young Conditions are Called as……
Scale leaf
Sporophyll
Circinate Ptyxis
None of these
Solution: C
5. Select below how many Neck Canal Cells are Present in Dryopteris?
One
Two
Many
None of these
Solution: A
Some Extra MCQs
1. Club Mosses are:
(a) Lycopsida
(b) Pteropsida
(c) Psilopsida
(d) Sphenopsida
2. The Protostele in Which Xylem Core is Smooth and Rounded is:
(a) Haplostele
(b) Actinostlele
(c) Plectostele
(d) Siphonostele
3. The Siphonostele in–Which Two Cylinders of Vascular Tissue are Present in the Stele is:
(a) Haplostele
(b) Actinostlele
(c) Plectostele
(d) Polycyclic
4. In Xylem in Which Protoxylem is Lying in the Middle of Metaxylem is:
(a) Exarch
(b) Mesarch
(c) Endarch
(d) Diarch
5. The Stele in Which Xylem Forms Several Plates is:
(a) Haplostele
(b) Actinostlele
(c) Plectostele
(d) Polycyclic
6. The Xylem in Which Protoxylem is Lying on the Periphery of Metaxylem is:
(a) Exarch
(b) Mesarch
(c) Endarclt
(d) Diarch
7. The Triad of Sporangia is Called:
(a) hirers
(c) Jacket
(d) tapetum
8. the Primary Androgonial Cell Divides to Produces a Mass of:
(a) Androgonial
(b) astrocytes
(c) Antherozold
(d) None
FAQs on MCQs on Pteridophyta
1. What are the key characteristics of Pteridophytes?
Pteridophytes are the first terrestrial plants to possess vascular tissues (xylem and phloem). Their main characteristics include:
- Plant Body: The main plant body is a sporophyte, which is differentiated into true roots, stem, and leaves.
- Habitat: They are commonly found in cool, damp, and shady places.
- Vascular Tissue: They possess well-developed conducting tissues, xylem and phloem.
- Reproduction: They reproduce via spores produced in sporangia, not by seeds.
- Life Cycle: They exhibit a distinct alternation of generations between a dominant sporophyte and a smaller, independent gametophyte (prothallus).
2. Why are Pteridophytes often called 'vascular cryptogams'?
Pteridophytes are called 'vascular cryptogams' for two primary reasons:
- Vascular: They are the first group of plants to have a well-developed vascular system, consisting of xylem for water transport and phloem for food transport. This allows them to grow larger than non-vascular plants like bryophytes.
- Cryptogams: The term 'cryptogam' (from Greek 'kryptos' for hidden and 'gamos' for marriage) refers to plants that do not produce flowers or seeds. Their reproductive organs are concealed, and they reproduce through spores.
Thus, they are 'vascular' due to their tissues and 'cryptogams' due to their spore-based reproduction.
3. How does the life cycle of a Pteridophyte show a significant evolutionary advancement over Bryophytes?
The life cycle of a Pteridophyte represents a major evolutionary step up from Bryophytes. The most significant advancement is the change in the dominant phase. In Bryophytes, the main plant body is the gametophyte, and the sporophyte is small and dependent on it for nutrition. In Pteridophytes, the roles are reversed: the sporophyte is the dominant, independent, and photosynthetic plant body with true roots, stems, and leaves, while the gametophyte (prothallus) is small and free-living.
4. What is the difference between homosporous and heterosporous Pteridophytes?
The difference lies in the types of spores they produce:
- Homosporous Pteridophytes: These plants produce only one type of spore. These spores germinate to form a bisexual gametophyte (prothallus) that bears both male (antheridia) and female (archegonia) sex organs. Most Pteridophytes, like ferns (Dryopteris) and Lycopodium, are homosporous.
- Heterosporous Pteridophytes: These plants produce two distinct types of spores: smaller microspores (male) and larger megaspores (female). Microspores develop into male gametophytes, and megaspores develop into female gametophytes. Examples include Selaginella and Salvinia.
5. What is the importance of stelar evolution in Pteridophytes?
The stele is the central core of the stem and root containing the vascular tissues. The evolution of the stele in Pteridophytes is significant as it shows a progression towards greater structural complexity and transport efficiency. The primary types are:
- Protostele: The simplest type, with a solid core of xylem surrounded by phloem. It is found in primitive Pteridophytes.
- Siphonostele: A more advanced type where the vascular cylinder has a central pith (non-vascular parenchyma). This arrangement provides better support and more efficient transport, allowing for the development of larger stems and leaves.
This evolutionary trend from a simple solid core to a hollow, more organized cylinder was crucial for the development of larger and more complex plant forms.
6. How do Pteridophytes fundamentally differ from seed-bearing plants like Gymnosperms?
The fundamental difference lies in their method of reproduction and dispersal. Pteridophytes are non-seed-bearing plants that reproduce and disperse through spores. Their gametophyte is typically a free-living structure requiring water for fertilisation. In contrast, Gymnosperms are seed-bearing plants. They produce seeds, which contain a well-protected embryo with a stored food supply. This seed habit offers superior protection and a higher chance of survival for the offspring, making it a major evolutionary advantage.
7. Why is heterospory in Pteridophytes considered a precursor to the seed habit?
Heterospory, the production of two types of spores (microspores and megaspores), is a critical evolutionary step towards seed formation for several reasons:
- Development of Unisexual Gametophytes: It leads to separate male and female gametophytes, promoting cross-fertilisation.
- Retention of the Megaspore: In heterosporous species like Selaginella, the female gametophyte develops inside the megaspore, which is retained on the parent sporophyte.
- In-situ Zygote Development: Fertilisation and the early development of the embryo (zygote) occur while the female gametophyte is still attached to and nourished by the parent plant.
This retention and nourishment of the embryo on the parent sporophyte is the essential characteristic of the seed habit, making heterospory a vital prerequisite.
8. What is a prothallus and what is its role in the fern life cycle?
A prothallus is the gametophyte stage in the life cycle of a fern. It is typically a small, green, heart-shaped, and short-lived structure that is independent of the main sporophyte plant. Its primary role is sexual reproduction. The prothallus bears the sex organs: antheridia (producing male gametes) and archegonia (producing the female egg). Fertilisation occurs on the prothallus, usually requiring a film of water, leading to the formation of a zygote which then grows into the new dominant sporophyte (the fern plant we see).
