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Questions Related to evs

All gymnosperms are

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Heterosporous

  2. Arborescent

  3. Seed plants

  4. All of the above

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Correct Option: D
Explanation:

"Gymnosperms" include all seed plants other than the angiosperms, or flowering plants. The absence of an enclosing structure is believed to be primitive, thus the first seed plants were "gymnosperms. 

Gymnosperms are heterosporous i.e., produce two types of spores- microspores (pollen grains) and megaspores.
Arborescent means having the shape or characteristics of a tree. The gymnosperms are also arborescent.

Which of the following pair of example will correctly represent the group Spermatophyta, according to one of the schemes of classifying plants?

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Acacia, Sugarcane

  2. Pinus, Cycas

  3. Rhizopus, Triticum

  4. Ginkgo, Pisum

Show answer
Correct Option: D
Explanation:

The term Spermatophyta refers to any of a group of higher plants, that produce seeds.  

While there are many schemes of classifying plants, on a broader level the seed plants are classified as angiosperms and gymnosperms. The gymnosperms are plants with 'naked seeds', and it is because the ovule is exposed to the environment and is not covered by a protective layer. 
In contrast in angiosperms, the ovule is contained within a specialized
structure, the carpel. As examples of these two divisions, Ginkgo represents the gymnosperms, while Pisum (Garden pea) from the family Fabaceae correcty represents the angiosperms.

Plant group with largest ovule, largest tree and largest gametes is

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Gymnosperm

  2. Angiosperm

  3. Bryophyta

  4. Pteridophyta

Show answer
Correct Option: A
Explanation:

Gymnosperms refers to the group of naked seed bearing vascular  plants. Their seeds are naked as these are not enclosed in an ovary, like that of the angiosperms. This group includes large trees, like the pines, conifers, cycads and Ginkgo. 

The reproductive structure of gymnosperms is the strobili (cone), which consists of an ovoid, cylindrical, or spherical cluster of sporophylls (cone scales) arranged around a central axis and differ largely in size from the small pollens and ovules of angiosperms.

The "endosperm" of a gymnosperm represent

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Gametophytic tissue

  2. Sporophytic tissue

  3. Tissue formed by double fertilization

  4. Polyploid tissue

Show answer
Correct Option: A
Explanation:

The "endosperm" is a tissue in which the nutrient substances necessary for the development of the embryo are deposited. In gymnosperms the endosperm is formed in the ovule during germination of the megaspore is a gametophytic tissue, which consequently becomes the female prothallus or the gametophyte with a haploid set of chromosomes. The archegonia in gymnosperms develop from certain cells of the endosperm.

In gymnosperms, the pollen chamber represents

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. The microsporangium in which pollen grains develop.

  2. A cell in the pollen grain in which the sperms are formed.

  3. A cavity in the ovule in which pollen grains are stored after pollination.

  4. An opening in the megagametophyte, through which the pollen tube approaches the egg.

Show answer
Correct Option: C
Explanation:

In gymnosperms, below micropylar beak some of the cells of nucellus of ovule disintigerate to form pollen chamber.

The process of pollination in gymnosperms involves the help of pollination droplet from the micropyle, which drops when pollen grains are shed. This droplet catches the pollen grains and carries it into the pollen chamber for fertilizing the ovule.  
After pollination the droplet evaporates and contracts, carrying the pollen grains into the pollen chamber and into contact with the ovule.

Nonflowering plants are _________.

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Dicots

  2. Monocots

  3. Phanerogams

  4. Cryptogams.

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Correct Option: D

Gymnosperms are naked seeded plants because

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. There is no fruit

  2. There is no ovule

  3. There is no fertilization

  4. There is no ovary and fruit.

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Correct Option: D

Pollen chamber present in gymnosperms represents _________________.

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Microsporangium

  2. Pollen grain cell where sperms are formed

  3. Opening of megagametophyte for passage of pollen tube to egg

  4. Cavity in nucellus for resting pollen grains after pollination.

Show answer
Correct Option: D

Siphonogamy is a reproductive process in plants that produce seeds. In this process, a pollen tube carries the sperm cells to the egg located within the integumented megasporangium. Which group of plants exhibit this process?

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Pteridophytes

  2. Bryophytes

  3. Thallophytes

  4. Gymnosperms

Show answer
Correct Option: D
Explanation:

Gymnosperms are wind-pollinated plants. They do not have to cover around seeds. They do not produce fruits or flowers. After pollination, they produce pollen tubes. This pollen tube carries the sperm cells to the egg. These eggs are located within the integument megasporangium. So, all these are the characteristics of gymnosperms.

So, option G "Gymnosperms" is the correct answer.

Plants of this group are diploid and were adapted to extreme conditions. They grow bearing sporophylls in compact structures called cones. The group in reference is

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Monocot

  2. Dicots

  3. Pteridophyta

  4. Gymnosperm

Show answer
Correct Option: D
Explanation:

Gymnosperms are woody, ever green trees. They are found where snow is the source of water and not rains. Their dominant plant body is sporophyte. It is differentiated into roots, stems and leaves. They are xerophytic due to presence of thick bark, scales, cuticles, sunken stomata etc.

So, option D "Gymnopserms" is the correct asnwer.