What is the Difference Between Anatropous and Orthotropous Ovule?
🆚 Go to Comparative Table 🆚The main difference between anatropous and orthotropous ovules lies in their orientation and the position of the micropyle with respect to the funicle and other structures. Here are the key differences:
Anatropous Ovule:
- Inverted or curved structure.
- Micropyle, chalaza, and funicle lie in the same line.
- Micropyle is located at the bottom, near the funicle.
- Body of the ovule fuses with the funicle.
- Most common type of ovule orientation, found in more than 80% of angiosperms.
- Common in monocots and dicots.
- In some cases, anatropous ovules are partly inverted, known as amphitropous ovules (90° inversion).
Orthotropous Ovule:
- Straight structure with no curvature.
- Micropyle, nucleus, chalaza, and funicle all lie in a straight line.
- Micropyle is located at the apex region.
- Funicle does not fuse with the ovule body.
- Less common compared to anatropous ovules.
- Primarily observed in plant families like Piperaceae and Polygonaceae.
In summary, anatropous ovules are more common and have an inverted or curved structure, while orthotropous ovules have a straight structure and are less abundant.
On this pageWhat is the Difference Between Anatropous and Orthotropous Ovule? Comparative Table: Anatropous vs Orthotropous Ovule
Comparative Table: Anatropous vs Orthotropous Ovule
Here is a table comparing the differences between anatropous and orthotropous ovules:
Feature | Anatropous Ovule | Orthotropous Ovule |
---|---|---|
Structure | Completely curved or inverted | Straight, without any curvature |
Micropyle Position | Located at the bottom | Located at the apex |
Hilum Position | Micropyle and hilum lie close to each other | Micropyle, hilum, and chalaza lie in one line |
Funicle Fusion | Body of the ovule is fused with the funicle on one side | Funicle is not fused with the ovule body |
Occurrence | Most common type of ovule orientation, found in more than 80% of angiosperms | Less abundant compared to anatropous, observed in plant families like Piperaceae and Polygonaceae |
Anatropous ovules are characterized by their inverted structure, with the micropyle tip directed towards the placenta and the chalazal end positioned at the top. In contrast, orthotropous ovules maintain a straight structure with the micropyle located at the apex.
Read more:
- Ovary vs Ovule
- Homospory vs Heterospory
- Antheridia vs Archegonia
- Homosporous vs Heterosporous Pteridophytes
- Sporophyte vs Gametophyte
- Spermatogenesis vs Oogenesis
- Parthenogenesis vs Parthenocarpy
- Apospory vs Apogamy
- Anamorph Teleomorph vs Holomorph
- Gamete vs Gametophyte
- Organogenesis vs Somatic Embryogenesis
- Ovary vs Uterus
- Pteridophytes vs Phanerogams
- Orthotropic vs Anisotropic
- Coenocytic vs Heterotrichous
- Ovum vs Egg
- Apomixis vs Polyembryony
- Sporogony vs Schizogony
- Sporangia vs Gametangia