NEET BIOLOGY

Detailed explanation-1: -The reproductive structures in gymnosperms are called cones or strobili. The strobili bearing microsporophylls and microsporangia are called microsporangiate or male strobili. The cones bearing megasporophylls with ovules or megasporangia are called macrosporangiate or female strobili.

Detailed explanation-2: -The reproductive system of gymnosperms is known as a strobilus. The male and female strobilus can be present on the same tree as in Pinus or can be present on a different tree as in Cycas. Sexual reproduction in gymnosperms takes place through the formation of spores.

Detailed explanation-3: -The ovules in angiosperms are encased in an ovary, not exposed on the sporophylls of a strobilus, as they are in gymnosperms. Angiosperm means “covered seed".

Detailed explanation-4: -A strobilus (plural: strobili) is a structure present on many land plant species consisting of sporangia-bearing structures densely aggregated along a stem. Strobili are often called cones, but some botanists restrict the use of the term cone to the woody seed strobili of conifers.

Detailed explanation-5: -In gymnosperms, when the nuclei of the two sperm meet the egg cell, one nucleus dies and the other unites with the egg nucleus to form a diploid zygote. The fertilized egg undergoes mitosis to begin the development of a new sporophyte generation-the multicellular embryo of the seed.