Question

Gnetum resemblance angiosperm in many respect, yet it is not places under Angiosperm why ❓​

Answer 1

Answer:

Both Gnetales and angiosperms originated from a common stalk called “Hemi-angiosperm”.

Thompson (1916) opined that the ancestors of both Gnetum and angiosperms were close relatives. Some other workers have gone up to the extent in stating that Gnetum actually belongs to angiosperms. Hagerup (1934) has shown a close relationship between Gnetales and Piperaceae.

In a beautiful monograph on Gnetum, Maheshwari and Vasil (1961) have stated that “Gnetum remains largely a phylogenetic puzzle. It is gymnospermous, but possesses some strong angiospermic features”.

Some of the resemblances between Gnetum and angiosperms are under mentioned:

1. The general habit of the sporophyte of many species of Gnetum resembles with angiosperms.

2. Reticulate venation in the leaves of Gnetum is an angiospermic character.

3. Presence of vessels in xylem is again an angiospermic character.

4. Clear tunica and corpus configuration of shoot apices is a character of both Gnetum and angiosperms.

5. Strobili of Gnetum resemble much more with angiosperms than any of the gymnosperms

6. Micropylar tube of Gnetales can be compared with the style of the angiosperms because both perform more or less similar functions.

7. Tetrasporic development of the female gametophyte is again a character which brings Gnetum close to angiosperms.

8. Absence of archegonia again brings Gnetum and angiosperms much closer.

9. Dicotyledonous nature of the embryo of Gnetum brings it quite close to the dicotyledons.

Answer 2

Few resemblances between the Gnetum and the angiosperms are given below:

• The "common habit of the sporophyte" of various species of Gnetum features with angiosperms.
• " Reticulate venation" in the Gnetum leaves is an 'angiospermic individuality'.
• Presence of vessels in xylem is again an angiospermic individuality.
• Clear tunica and corpus arrangement of shoot apices is a character of two together Gnetum and angiosperms.
• Strobili of Gnetum simulate much more with the 'angiosperms' than any of the 'gymnosperms'.

To know more:

What are embryologcal characters of Gnetum which resembles with that of the angiosperms?

https://brainly.in/question/6893843