With the help of a diagram, explain the structure of mature male gametophyte .

With the help of a diagram explain the structure of DNA.

Explain the structure of a mature female gametophyte in flowering plants.

With the help of diagrams, explain the development of female gametophyte from a megaspore mother cell in an angiosperm.

Explain the structure of matured pollen grain.

Withthe help of diagrams, explain the development of female gametophyte from a microspore in an angiosperm.

With the help of labelled diagram explain the structure of human respiratory system.

With the help of neat labelled diagram explain the structure of nucleus.

Explain the structure of Matured Pollen-grain.