Gymnosperms MCQ Quiz - Objective Question with Answer for Gymnosperms - Download Free PDF

The correct answer is Seeds are naked

Explanation:

• Gymnosperms are a group of seed-producing plants that include conifers, cycads, Ginkgo, and gnetophytes.
• The term "gymnosperm" comes from Greek words meaning "naked seed"
• The gymnosperms are plants in which the ovules are not enclosed by any ovary wall and remain exposed, both before and after fertilisation.
• The seeds that develop post-fertilisation, are not covered, i.e., are naked.
• Gymnosperms are vascular plants, meaning they have specialized tissues for transporting water and nutrients.
• They are predominantly woody trees and shrubs and are adapted to survive in various climatic conditions.

Other Options

• Seeds are enclosed in fruits: This statement refers to angiosperms, which are flowering plants. In angiosperms, seeds develop inside fruits formed from the ovary after fertilization.
• Seeds are absent: Gymnosperms are seed-producing plants.Plants without seeds are typically non-vascular plants like mosses or vascular plants like ferns, which reproduce via spores.
• Gymnosperms have flowers for reproduction: Flowers are a characteristic feature of angiosperms, not gymnosperms.

The correct answer is Two

Concept:

• Pinus and Cycas are genera of gymnosperms, which are seed-producing plants that do not form flowers or fruits.
• They reproduce using cones, which contain their reproductive structures.
• Mycorrhiza refers to a symbiotic association between fungi and plant roots, aiding in nutrient uptake.

Explanation:

• Pinus – Male cone: Correct. Pinus is known to produce male cones (also known as microsporangiate strobili) that contain pollen.
• Cycas – Female cone: Incorrect. Cycas does not have a typical female cone like Pinus. Instead, Cycas has megasporophylls  which may be clustered to form the female cones. The megaspore mother cell divides meiotically to form four megaspores.
• Pinus – Female cone: Correct. Pinus produce female cones
• Cycas – Mycorrhiza: Incorrect. Cycas does not typically form mycorrhizal associations; this is more common in other plant groups, including many angiosperms and some gymnosperms like Pinus.

The correct answer is A (ii), B (i), C (i)

Explanation:

• Roots in some genera have fungal association in the form of mycorrhiza (Pinus), while in some others (Cycas) small specialised roots called coralloid roots are associated with N₂-fixing cyanobacteria.
• The stems are unbranched (Cycas) or branched (Pinus, Cedrus).
• The leaves may be simple or compound. 

The correct answer is Cycas plants are monoecious

Explanation:

In Pinus, male and female cone/strobili borne on the same tree:

• This is correct. Pinus (pine trees) are monoecious, meaning they have both male and female cones on the same tree.

In Cycas, male cone and megasporophyll are born on different trees:

• This is correct. Cycas plants are dioecious, meaning male and female cones are borne on separate trees.

Cycas plants are monoecious:

• This is incorrect. Cycas plants are dioecious, meaning there are separate male and female plants.

The correct answer is Cyanobacteria

Concept:

• Coralloid roots are specialized roots found in Cycas plants that are associated with nitrogen fixation.
• Nitrogen fixation is the process of converting atmospheric nitrogen into a form that plants can use for growth, such as ammonia.
• This process is crucial for plant nutrition and growth, especially in environments where nitrogen is limited.

Explanation:

• Cyanobacteria: These are a group of photosynthetic bacteria that can fix atmospheric nitrogen. In coralloid roots of Cycas, cyanobacteria such as Anabaena and Nostoc form a symbiotic relationship with the plant. They convert atmospheric nitrogen into ammonia, which the plant can use for its growth. This symbiotic relationship is essential for the nitrogen economy of the plant and contributes significantly to its nutrient uptake.
• Mosses: Mosses are non-vascular plants that do not have the ability to fix nitrogen. They do not form a symbiotic relationship with Cycas roots for nitrogen fixation.
• Fungus: Fungi are primarily involved in forming mycorrhizal associations with plants, which help in water and nutrient uptake, especially phosphorus. However, they do not fix nitrogen in the coralloid roots of Cycas.

The correct answer is Seeds are naked

Explanation:

• Gymnosperms are a group of seed-producing plants that include conifers, cycads, Ginkgo, and gnetophytes.
• The term "gymnosperm" comes from Greek words meaning "naked seed"
• The gymnosperms are plants in which the ovules are not enclosed by any ovary wall and remain exposed, both before and after fertilisation.
• The seeds that develop post-fertilisation, are not covered, i.e., are naked.
• Gymnosperms are vascular plants, meaning they have specialized tissues for transporting water and nutrients.
• They are predominantly woody trees and shrubs and are adapted to survive in various climatic conditions.

Other Options

• Seeds are enclosed in fruits: This statement refers to angiosperms, which are flowering plants. In angiosperms, seeds develop inside fruits formed from the ovary after fertilization.
• Seeds are absent: Gymnosperms are seed-producing plants.Plants without seeds are typically non-vascular plants like mosses or vascular plants like ferns, which reproduce via spores.
• Gymnosperms have flowers for reproduction: Flowers are a characteristic feature of angiosperms, not gymnosperms.

Concept:

• Pteridophytes, Gymnosperms and Angiosperms are vascular plants.
• They are known as vascular plants as they possess xylem and phloem.
• Pteridophytes are the first vascular plants that possess vascular tissues.

Explanation:

• Xylem and phloem are complex tissues made up of different types of cells.
• In pteridophytes and gymnosperms, the xylem consists mainly of the tracheid, xylem fibers, and xylem parenchyma.
• Tracheid is the main water-conducting cell.
• Due to their absence of thick-walled vessels, which makes them softwood plants because vessels provide wood its strength, gymnosperms are also known as "softwood spermatophytes."
• Angiosperms on the other hand contain all four types of cells- tracheid, vessels, xylem fibers, and xylem parenchyma.
• Vessel elements are the main feature distinguishing the hardwood of angiosperms from the softwood of conifers.
• in Angiosperms, the tracheid, vessels, and fibers are all dead. The only living cell is the xylem parenchyma which stores food in it.

So, the correct answer is option 4.

Concept:

• Gymnosperms are plants in which seeds are not enclosed by an ovary wall or seed coat, that is, seeds formed post-fertilization are naked.
• Gymnosperms produce haploid microspores and megaspores, that is, they are heterosporous.
• Spores are formed within the sporangia which are born on sporophylls that form loose or compact strobili or cones when they are placed spirally along an axis.

Explanation:

• Gymnosperms include medium-sized trees or tall trees and shrubs.
• In Cycas small, specialized roots called coralloid roots are present.
• These roots are associated with Nitrogen-fixing cyanobacteria. The stems are unbranched (Cycas).
• In Cycas, the pinnate leaves persist for a few years.
• Citrulline and asparagine, which are two amino acids for plant growth, are produced as a result of nitrogen fixation.
• Anabaena is one such nitrogen-fixing cyanobacteria that is present in the coralloid roots of Cycas.

So, the correct answer is option 1, Anabaena.

Additional Information

• Chlamydomonas is a unicellular, green alga. They can exist in colonies or filaments. They contain chlorophyll a and chlorophyll b due to which they appear grass green color.
• Aulosira belongs to the genus Cyanobacteria. They form a symbiotic relationship with the roots of hornworts.

Correct answer: 1)

Solution:

Concept:

• Kingdom Plantae contains eukaryotic organisms.
• It includes algae, Bryophytes, Pteridophytes, Gymnosperms, and Angiosperms.

Explanation:

Option 1:

• Gymnosperms are seed-bearing vascular plants in which ovules/seed is not enclosed by the ovary wall. The word gymnosperms itself means naked seeds.
• They have needle-like leaves. They are generally found in colder regions.

Option 2:

• Selaginella and Salvinia both are pteridophytes.
• They both are heterosporous as they produce two different types of spores- microspores and megaspores.
• Microspores and megaspores form male and female gametophytes respectively.

Option 3:

• Cycas and Cedrus both belong to Gymnosperms.
• Cycas has unbranched stems whereas Cedrus has branched stems.

Option 4:

• Genus Equisetum is also known as horsetails.
• It is an example of pteridophyte and not Gymnosperms.

So, the correct answer is option 1. 

Concept:

• Kingdom Plantae is divided into Algae, Bryophytes, Pteridophytes, Gymnosperms, and Angiosperms.
• Cryptogams consist of seedless plants whereas phanerogams consist of seed-bearing plants.
• Algae, bryophytes, and pteridophytes are cryptogams whereas gymnosperms and angiosperms are phanerogams.

Explanation:

Option 1:

• The Pteridophytes include horsetails, club mosses, and ferns.
• They are the first vascular plants that possess vascular tissues, that is, the xylem and phloem.
• Club mosses belong to the family Lycopodiaceae. Also known as ground pine.
• They require water for fertilization.

Option 2:

• Ferns are also classified as Pteridophytes. Ferns have large leaves known as macrophytes.
• The main plant body is sporophyte which is differentiated into roots, stems, and leaves.
• They require water for fertilization.

Option 3:

• Gymnosperms are plants in which seeds are not enclosed by an ovary wall or seed coat, that is, seeds formed post-fertilization are naked.
• In gymnosperms, the male and female gametophytes do not live separately as free-living organisms.
• They continue to exist inside the sporangia on the sporophytes.
• From the microsporangium, the pollen grain is released.
• Pollen grains are carried through the air and encounter the opening of the ovules carried by megasporophylls.
• In the ovules, the pollen tube containing the male gametes expands toward the archegonia and releases its contents close to the archegonia's mouth.
• A zygote becomes an embryo after fertilization, and ovules become seeds. This crop of seeds is uncovered.

Option 4:

• Angiosperms are flowering plants. They bear, flowers, fruits, and seeds enclosed by an ovary wall.
• Ovules form seeds and the ovary forms fruit. Pollination is a method of transfer of pollen grains/male gamete/sperm from the anther to the stigma of the flower.
• Pollination can occur by wind, water, air, birds, insects, bats, snails, etc.

So, the correct answer is Option 3: Gymnosperms.

Concept:

• Gymnosperms are plants in which seeds are not enclosed by an ovary wall or seed coat, that is, seeds formed post-fertilization are naked.
• Gymnosperms produce haploid microspores and megaspores, that is, they are heterosporous.
• Spores are formed within the sporangia which are born on sporophylls that form loose or compact strobili or cones when they are placed spirally along an axis.

Explanation:

• Gymnosperms include medium-sized trees or tall trees and shrubs.
• In Cycas small, specialized roots called coralloid roots are present.
• These roots are associated with Nitrogen-fixing cyanobacteria. The stems are unbranched (Cycas).
• In Cycas, the pinnate leaves persist for a few years.
• Citrulline and asparagine, which are two amino acids for plant growth, are produced as a result of nitrogen fixation.
• Anabaena is one such nitrogen-fixing cyanobacteria that is present in the coralloid roots of Cycas.

So, the correct answer is option 1, Anabaena.

Additional Information

• Chlamydomonas is a unicellular, green alga. They can exist in colonies or filaments. They contain chlorophyll a and chlorophyll b due to which they appear grass green color.
• Aulosira belongs to the genus Cyanobacteria. They form a symbiotic relationship with the roots of hornworts.

Concept:

• Gymnosperms are plants in which seeds are not enclosed by an ovary wall or seed coat, that is, seeds formed post-fertilization are naked.
• Gymnosperms produce haploid microspores and megaspores, that is, they are heterosporous.
• Spores are formed within the sporangia which are born on sporophylls that form loose or compact strobili or cones when they are placed spirally along an axis.

Explanation:

• Gymnosperms include medium-sized trees or tall trees and shrubs.
• In Cycas small, specialized roots called coralloid roots are present.
• These roots are associated with Nitrogen-fixing cyanobacteria. The stems are unbranched (Cycas).
• In Cycas, the pinnate leaves persist for a few years.
• Citrulline and asparagine, which are two amino acids for plant growth, are produced as a result of nitrogen fixation.
• Anabaena is one such nitrogen-fixing cyanobacteria that is present in the coralloid roots of Cycas.

So, the correct answer is option 1, Anabaena.

Additional Information

• Chlamydomonas is a unicellular, green alga. They can exist in colonies or filaments. They contain chlorophyll a and chlorophyll b due to which they appear grass green color.
• Aulosira belongs to the genus Cyanobacteria. They form a symbiotic relationship with the roots of hornworts.

The correct answer is Ovary

Explanation:

• Gymnosperms lack fruit because they lack an ovary.
• In gymnosperms, the ovules are exposed on the surface of scales or leaves and are not enclosed within an ovary as they are in angiosperms.
• Fruits are structures that develop from the ovary after fertilization and contain the seeds.
• Therefore, the correct answer is Ovary

The correct answer is Seeds are naked

Explanation:

• Gymnosperms are a group of seed-producing plants that include conifers, cycads, Ginkgo, and gnetophytes.
• The term "gymnosperm" comes from Greek words meaning "naked seed"
• The gymnosperms are plants in which the ovules are not enclosed by any ovary wall and remain exposed, both before and after fertilisation.
• The seeds that develop post-fertilisation, are not covered, i.e., are naked.
• Gymnosperms are vascular plants, meaning they have specialized tissues for transporting water and nutrients.
• They are predominantly woody trees and shrubs and are adapted to survive in various climatic conditions.

Other Options

• Seeds are enclosed in fruits: This statement refers to angiosperms, which are flowering plants. In angiosperms, seeds develop inside fruits formed from the ovary after fertilization.
• Seeds are absent: Gymnosperms are seed-producing plants.Plants without seeds are typically non-vascular plants like mosses or vascular plants like ferns, which reproduce via spores.
• Gymnosperms have flowers for reproduction: Flowers are a characteristic feature of angiosperms, not gymnosperms.

The correct answer is Two

Concept:

• Pinus and Cycas are genera of gymnosperms, which are seed-producing plants that do not form flowers or fruits.
• They reproduce using cones, which contain their reproductive structures.
• Mycorrhiza refers to a symbiotic association between fungi and plant roots, aiding in nutrient uptake.

Explanation:

• Pinus – Male cone: Correct. Pinus is known to produce male cones (also known as microsporangiate strobili) that contain pollen.
• Cycas – Female cone: Incorrect. Cycas does not have a typical female cone like Pinus. Instead, Cycas has megasporophylls  which may be clustered to form the female cones. The megaspore mother cell divides meiotically to form four megaspores.
• Pinus – Female cone: Correct. Pinus produce female cones
• Cycas – Mycorrhiza: Incorrect. Cycas does not typically form mycorrhizal associations; this is more common in other plant groups, including many angiosperms and some gymnosperms like Pinus.