JIPMER 2009
- Exam
- JIPMER
- Year
- 2009
- Subject
- Botany
- Chapter
- Plant Kingdom
JIPMER 2009 · Botany · Plant Kingdom
In Pinus, male cone bears a large number of
In Pinus, male cone bears a large number of
Options
- Aligules
- Banthers
- Cmicro-sporophylls
- Dmega-sporophylls
Correct answer
C. micro-sporophylls
Step-by-step solution
Microsporophylls andmegasporophylls are the leaf-like structures on which microsporangia (pollen sacs) and magasporangia are borne on the same plant of Pinus. The sporophylls are aggregated in form of cones.
(a) Male cones are smaller, also known as microstrobili (staminate strobili).
(b) Female cones are larger, known as macrostrobili (ovulate strobili).Each male cone consists of an elongated axis, bearing a number of spirally arrangedmicrosporophylls. On the underside of which two microsporangia develop and get filled with microspores (pollen grains).Anther ormicrosporangium is the male reproductive structures ofangiosperms. Microsporangium forms microspores (pollens), through microsporogenesis.Ligule is a tongue-like membranous outgrowth, present on upper surface, near the base of the microphyllous leaf in pteridophytes (eg, Selaginella). The ligule shrinks and becomes inconspicuous in mature leaves.