Tag: evs

Questions Related to evs

The characters of gymnosperms are

  1. Seeds are naked

  2. Fruits are absent

  3. True carpel absent

  4. All of the above


Correct Option: D
Explanation:

Gymnosperms were the first plants to have seeds. They are often referred to as having naked seeds because they do not have flowers and they develop on the surface of the reproductive structures of the plants rather than being contained in a specialized ovary. These seeds are often found on the surface of cones and short stalks.

Gymnosperms are a group of plants with the following unique characteristics:

  • They do not have an outer covering or shell around their seeds.
  • They do not produce flowers.
  • They do not produce fruits.
  • They are pollinated by the wind.

Gymnosperms maintain their dominance over angiosperms in

  1. Colder regions of world

  2. Warmer regions of world

  3. Antarctica

  4. Oceans


Correct Option: A
Explanation:

Gymnosperms are more ancient than angiosperms. They formed dominant vegetation on the earth about 200 million years ago, and have been replaced by the angiosperms with the changing time and climatic conditions. They are now maintaining their dominance only in the colder regions, where instead of rain, snow is the source of water. Only a few gymnosperms, like cycads thrive in warm whether.

Dwarf shoot of Pinus is

  1. Shed every year

  2. Shed after 2 - 3 years

  3. Shed after five years

  4. Never shed


Correct Option: B

In gymnosperms how many male gametes are produced by each pollen grain?

  1. $4$

  2. $3$

  3. $2$

  4. $1$


Correct Option: C

The gymnosperms endosperm differs from an angiospermic endosperm because in gymnosperms it is

  1. Haploid and developed from female gametophyte

  2. Diploid and developed from female gametophyte

  3. Triploid and developed after fertilization

  4. Triploid and developed before fertilization


Correct Option: A

Vascular plants lacking vessels and companion cells are

  1. Angiosperms

  2. Thallopohytes

  3. Bryophytes

  4. Gymnosperms


Correct Option: D

Gymnosperm wood is soft as it

  1. Lacks cambium

  2. Lacks vessels

  3. Does not yield timber

  4. None of the above


Correct Option: B
Explanation:

The secondary xylem in gymnosperms does not contain vessels. So it is called soft wood or non-porous wood.

So, the correct option is 'Lacks vessels'.

Gymnosperm wood is non-porous because it

  1. Lacks vessels

  2. Contains tracheae

  3. Has abundant fibres

  4. Contains no fibres


Correct Option: A
Explanation:

The secondary xylem or wood of gymnosperms, vessels are absent. So it is called non porous wood.

So, the correct option is ‘lacks vessels’.

A spermatophyte with ciliated stage is 

  1. Gymnosperm

  2. Riccia

  3. Angiosperm

  4. Pteridium


Correct Option: A

Both pteridophytes and gymnosperms possess 

  1. Ovules

  2. Seeds

  3. Archegonia

  4. Independent gametophyte


Correct Option: C