Tag: gymnosperms

Quizzes (0) Questions (292)

Questions Related to gymnosperms

Multiple choice evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

Zoodiogamy takes place in

  1. Lower gymnosperms

  2. Higher gymnosperms

  3. Angiosperms

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Zoodiogamy is a type of fertilization in plants, wherein the male gametes or antherozoids swim in a film of water to the female gametes present in the archegonium. This type of plant reproduction relates to evolution and  is found in lower gymnosperms besides algae, bryophytes and pteridophytes.

Multiple choice evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

All gymnosperms are

  1. Heterosporous

  2. Arborescent

  3. Seed plants

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
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.

Multiple choice evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

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

  1. Acacia, Sugarcane

  2. Pinus, Cycas

  3. Rhizopus, Triticum

  4. Ginkgo, Pisum
Reveal answer Fill a bubble to check yourself
D Correct answer
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.

Multiple choice evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

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

  1. Gymnosperm

  2. Angiosperm

  3. Bryophyta

  4. Pteridophyta
Reveal answer Fill a bubble to check yourself
A Correct answer
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.

Multiple choice evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

The "endosperm" of a gymnosperm represent

  1. Gametophytic tissue

  2. Sporophytic tissue

  3. Tissue formed by double fertilization

  4. Polyploid tissue
Reveal answer Fill a bubble to check yourself
A Correct answer
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.

Multiple choice evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

In gymnosperms, the pollen chamber represents

  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.
Reveal answer Fill a bubble to check yourself
C Correct answer
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.

Multiple choice evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

Gymnosperms are naked seeded plants because

  1. There is no fruit

  2. There is no ovule

  3. There is no fertilization

  4. There is no ovary and fruit.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Gymnosperms are called 'naked-seeded' because their ovules are not enclosed within an ovary wall, and therefore they do not form fruits after fertilization.

Multiple choice evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

Pollen chamber present in gymnosperms represents _________________.

  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.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In gymnosperms, the pollen chamber is a cavity formed in the nucellus of the ovule where pollen grains land and rest before germination.

Multiple choice evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

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?

  1. Pteridophytes

  2. Bryophytes

  3. Thallophytes

  4. Gymnosperms
Reveal answer Fill a bubble to check yourself
D Correct answer
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.