Lilium Ovary Labeled – Cross Section, Ovule, Embryo Sac

All 12 parts on the diagram

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The ovary 5

Ovary wall The outer wall of the ovary. It encloses the chambers.
Locule A chamber of the ovary. A lily ovary has three.
Ovule A body that can become a seed. Two rows fill each chamber.
Placenta The tissue the ovules are attached to. Here it is the middle of the ovary.
Septum A wall between two chambers. The joined edges of the carpels form it.

One ovule 7

Embryo sac A large cell inside the nucellus. The egg forms in it.
Nucellus The tissue inside the coats. The embryo sac lies in it.
Inner integument The inner coat of the ovule.
Outer integument The outer coat of the ovule.
Micropyle A narrow opening left by the coats. The pollen tube enters here.
Funiculus The stalk of the ovule. It joins the ovule to the placenta.
Chalaza The base of the ovule, where the coats and the nucellus join.

How this list was compiled: Every name checked on 2026-10-03 and kept only where two of these use it. (1) C. S. Gager, Fundamentals of Botany, 1916, the chapter on angiosperms (public domain), https://archive.org/details/fundamentalsofbo00gagerich : the carpels as walls of the ovary; the placenta, the point of attachment of the ovules; figure 326 names the ovary wall, the ovule containing the embryo-sac, the inner integument, the outer integument, the funiculus, the chalaza and the nucellus (megasporangium); the micropyle; the embryo-sac as the female gametophyte. (2) E. Strasburger and others, A Text-Book of Botany, second English edition, 1903 (public domain), https://archive.org/details/textbookofbotany00stra_1 : a syncarpous ovary is plurilocular when the coherent margins of the carpels extend to the axis; the double walls or dissepiments of a plurilocular ovary; ovules in plurilocular ovaries axile; the funiculus; nucellus, embryo-sac and micropyle. (3) Britton and Brown, An Illustrated Flora of the Northern United States and Canada, 2nd ed. 1913, vol. 1, the genus Lilium (public domain), https://archive.org/details/illustratedflora01brit : ovary 3-celled, ovules numerous; seeds packed in 2 rows in each cavity. (4) J. M. Coulter and C. J. Chamberlain, Morphology of Angiosperms, 1903 (public domain), https://archive.org/details/morphologyofangi00coulrich : multilocular ovaries; by far the most common form of ovule is the anatropous. (5) Wikipedia, text only, Ovule, Locule, Placentation and Liliaceae, https://en.wikipedia.org/wiki/Ovule , https://en.wikipedia.org/wiki/Locule , https://en.wikipedia.org/wiki/Placentation : ovules attached to the placenta through a stalk known as a funiculus; a locule is a chamber within an ovary; in axile placentation the carpels fuse to form septa and the ovules are arranged on the central axis, as in the lily; the nucellus, the inner and outer integuments, the micropyle and the chalazal end; the megagametophyte is also named the embryo sac; in an anatropous ovule the micropyle faces the placenta. The wall between two chambers is 'septum' in (5) and 'dissepiment' in (2): the quiz takes both. Licence: own work

The drawing: Drawn for this site on 2026-10-03 from plain geometry; own work, nothing traced. Licence: own work

How it works

A lilium ovary labeled here is cut across, as a microscope slide shows it: three chambers with ovules in each. The second drawing enlarges one ovule, cut lengthwise.

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The cut face

A lily ovary is made of three joined carpels. Their edges turn in and meet at the middle, so the section shows three locules with a septum between each pair. The placenta is at the middle, and the ovules are attached to it in two rows to a locule.

Inside one ovule

A stalk, the funiculus, joins the ovule to the placenta. Two coats, the outer and inner integuments, wrap the nucellus and leave a narrow opening, the micropyle. The embryo sac lies inside the nucellus. The chalaza is the base of the ovule, at the end away from the micropyle.

The ovule is drawn turned over on its stalk, so its micropyle faces the placenta. Most ovules of flowering plants grow this way.
Older books call a septum a dissepiment, and a locule a cell. The quiz takes these.

Questions and answers

How many locules does a lily ovary have?

Three. The ovary is made of three joined carpels, and a cross section shows three chambers around a central axis, with the ovules in two rows in each.

What is the placenta in a lily ovary?

The tissue the ovules are attached to. In a lily it lies at the middle of the ovary, where the three septa meet. This arrangement is called axile placentation.

What is the embryo sac?

The female gametophyte of a flowering plant: a large cell inside the nucellus of the ovule. The egg forms in it, at the end near the micropyle.

What is the difference between an ovary and an ovule?

The ovary is the hollow base of the pistil. The ovules are the small bodies inside it. After fertilization an ovule becomes a seed and the ovary becomes the fruit.