Tag: phanerogams

Questions Related to phanerogams

Choose the correct answers from the alternatives given.
Ovules are not found enclosed within ovary in

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. gymnosperms

  2. spermatophytes

  3. dicotyledons

  4. monocotyledons

Show answer
Correct Option: A
Explanation:

Gymnosperms are seed-bearing vascular plants like cycads, conifers, yews and ginkgo in which the ovules are not enclosed in an ovary. So, the ovules are called naked. 

Hence, the correct answer is 'gymnosperms'.

Choose the correct answers from the alternatives given.
Which one of the following characteristics can be used to distinguish gymnosperms from angiosperms?

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Presence of pollen chamber in gymnosperms

  2. Presence of naked ovules in gymnosperms

  3. Presence of stomata in angiosperms

  4. Absence of naked ovules in gymnosperms

Show answer
Correct Option: B
Explanation:

Gymnosperms are the plants in which the ovules are not covered by an ovary, and the plant does not bear flowers. The seeds are naked.

So, the correct option is 'Presence of naked ovules in gymnosperms'

Which of the following is correct?

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. ln Pinus pollen grain are developed inside the megasporangia

  2. Coralloid roots are associated with Frankia

  3. Male and female cones are borne on the same tree in Pinus

  4. In Cycas the pinnate leaves persist for upto only few days

Show answer
Correct Option: C
Explanation:
A cone is a structure present on conifers that contain the reproductive organs. The male and female cones are borne on the same tree in Pinus.

So, the correct answer is 'Male and female cones are borne on the same tree in pinus'.

Which of the following is the best evidence that gymnosperms have descended from pteridophytes?

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Some gymnosperms have ciliated sperms

  2. They have cones

  3. They have evergreen

  4. Some gymnosperms cannot bear fruit

Show answer
Correct Option: A
Explanation:

Gymnosperms and angiosperms, sperm cells have no cilia. All other motile land plant sperm cells are released into the environment.

So, the correct option is 'Some gymnosperms have ciliated sperms'.


A female gymnospermic plant has the genotype TT which pollinates another gymnosperms with the genotype tt. As a result of fertilization what will be the genotype of embryo and endosperm respectively?

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Tt, T

  2. Tt, TTt

  3. tt, Tt

  4. TTt, Tt

Show answer
Correct Option: B
Explanation:
  • The endosperm is the storage tissue in the seeds of gymnosperms.
  • The genotype obtained in the $F _1$ generation will be Tt, when a homozygous gymnospermic plant (TT) is crossed with another (tt).
  • Thus, the embryo being diploid in nature will have the genotype Tt.
  • Whereas, the genotype of the endosperm will be TTt because it is triploid in nature. 

What is the number of neck canal cells in the archegonium of Gnetales?

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. 0

  2. 4

  3. 8

  4. 16

Show answer
Correct Option: A
Explanation:

There are no archegonia in Gnetales. Hence, there will be no neck canal cells.

The total number of species belonging to present day gymnosperms is about

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. 2000

  2. 850

  3. 2500

  4. 4000

Show answer
Correct Option: B
Explanation:

The total number of living gymnosperms of the world is about 850 species, belonging to 79 genera of 15 families. Although the number of species of gymnosperms accounts for only 0.36% of that of the angiosperms, they have formed large areas of various kinds of coniferous forests and are widely distributed all over the world, especially on mountains from middle to alpine latitudinal zones in cold-temperate and subtropical latitudes of the Northern hemisphere.

Therefore, the correct answer is option B.

Sieve cells can be traced in

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Dicots and monocots

  2. Monocots

  3. Gymnosperms and pteridophytes

  4. Bryophytes

Show answer
Correct Option: C
Explanation:

Sieve cells can be traced in gymnosperms and pteridophytes. Sieve cells are typically associated with gymnosperms because angiosperms have the more derived sieve tube members and companion cells in their phloem. They have a narrower diameter and are more elongated compared to sieve tube members. Sieve cells are associated with albuminous cells, which lack starch thus, making it possible to differentiate them from phloem parenchyma.
Therefore, the correct answer is option C.

The resin duct of Gymnosperm is an example of

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Intracellular space

  2. Schizogenous cavity

  3. Lysigenous cavity

  4. Vacuole containing stored material

Show answer
Correct Option: B
Explanation:

The resin duct in Gymnosperms are formed by separation of cells to form a cavity. The cells surrounding this cavity secrete resin into the cavity. Resin is aromatic and prevents infection. 

So, the correct answer is 'Schizogenous cavity'

Ovules are naked in gymnosperm, because

evs flowers and fruits phanerogams gymnosperms pictorial feature of plant kingdom

  1. Fertilisation is absent

  2. True carpels are absent

  3. Archegonia are absent

  4. Endosperm is absent

Show answer
Correct Option: B
Explanation:

The gymnosperms do not have petals or flowers, but they do produce seeds. The name 'Gymnosperm' means, 'naked seeds' and refers to the fact that the gymnosperms bears their seeds on the margins of modified leaves or cones. 

There are no sealed carpels, like those the define angiosperms. Although gymnosperms do have ovules, they do not have ovaries, pistils or stamens. Since the term 'fruit' refers to the mature ovary, gymnosperms do not in botanical usage have 'fruit' and the reproductive stages are referred to as cones.