Page 50 - Pharmacognosy-I (02-06-06-102)
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Gynaecium
The gynaecium or pistil is the female sexual organ of the flower. It
consists of one, two or more carpels and according to their number
the gynaecium is described as monocarpellary (one), bicarpellary
(two), or multicarpellary (more).
Cohesion of carpels:
The carpels may be either:
1- Apocarpous: Free carpels.
2- Syncarpous: United carpels.
The carpels are usually sessile, rarely raised on stalk-like
structure called carpophore.
The carpel is a modified leaf, folded on itself and its margins
cohere forming the ventral suture or joined with the margins of
other carpels. The midrib is prominent on the opposite edge of the
free carpel forming the dorsal suture.
A typical carpel consists of three parts:
1- Ovary: It is the hollow basal portion of the carpel encloses
several ovules arranged on the two thickened cohering margins
of the carpel which is termed placenta.
2- Stigma: It is the apical portion of the carpel, usually swollen,
and covered with papillae or glandular projection to receive the
pollen grains.
3- Style: It is the slender stalk-like connecting the ovary with the
stigma.
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