The main difference between actinomorphic and zygomorphic flower is that actinomorphic flower is radially symmetrical, whereas zygomorphic flower is bilaterally symmetrical.
Floral symmetry refers to how the flowers can be divided into mirror image parts. Some flowers are radially symmetrical, some are bilaterally symmetrical, and some are asymmetrical.
Key Areas Covered
1. What is an Actinomorphic Flower
– Definition, Structure, Features
2. What is a Zygomorphic Flower
– Definition, Structure, Features
3. Similarities Between Actinomorphic and Zygomorphic Flower
– Outline of Common Features
4. Difference Between Actinomorphic and Zygomorphic Flower
– Comparison of Key Differences
Actinomorphic Flower, Zygomorphic Flower
What is an Actinomorphic Flower
An actinomorphic flower is a radially symmetrical flower. That means you can divide the flower into two equal parts along any diameter. In fact, many flowers are actinomorphic. Generally, actinomorphic flowers have star shapes. They are also called regular flowers because their floral organs are equal in size. Moreover, you can get two equal halves when you bisect actinomorphic flowers along any diameter.
Examples of actinomorphic flowers are butter cups, lilies, tulips, and roses. These types of flowers are commonly available in the families Rosaceae, Asteraceae, and Ranunculaceae. Flowers of these families typically consist of multiple petals in a circular pattern around the central point. They also have a prominent center disk that contains the reproductive organs of the flower.
Having an actinomorphic flower allows efficient pollination by a wider range of pollinators. Pollinators can approach the flower and access nectar and pollen in any direction as the flower is symmetrical. Therefore, a diverse range of pollinators like bees, butterflies, and moths visit actinomorphic flowers.
The symmetry of this flower also helps the pollinators to recognize and locate the flower easily as the colour and shape are consistent from every angle possible.
Actinomorphic flowers have another advantage as they are easier to produce and maintain due to their symmetrically arranged parts that do not require a complex development process.
What is a Zygomorphic Flower
A zygomorphic flower is a flower having bilateral symmetry. This means we can divide them into two identical images using only one plain. The floral parts of zygomorphic flowers are unequal in size. The petals of the corolla are especially unequal in size. Therefore, they are irregular flowers.
Zygomorphic flowers are highly specialized for pollination by specific pollinators such as bees and butterflies. The flower’s bilateral symmetry guides the pollinator towards the nectar or pollen-bearing structure deep inside. The shape and the size of the flower also help to attract pollinators.
Orchid is an example of a zygomorphIc flower. Orchids have highly specialized complex structures that are designed to attract specific pollinators such as moths and bees. The lip and the reproductive structures of the flowers, including the pistil and stamen, are also highly modified for successful pollination. Another example of such a highly complex structured flower is the snapdragon.
Zygomorphic flowers are a derived character of the angiosperms. There are three types of zygomorphic flowers, and they are; zygomorphic, transversely zygomorphic, and obliquely zygomorphic.
Similarities Between Actinomorphic and Zygomorphic Flowers
- Both types of flowers give mirror images when bisected.
Difference Between Actinomorphic and Zygomorphic Flowers
An actinomorphic flower is a radially symmetrical flower, whereas a zygomorphic flower is a bilaterally symmetrical flower.
Regular or Irregular Nature
Actinomorphic flowers are regular flowers, whereas zygomorphic flowers are irregular flowers.
Mirror images can be obtained along any diameter in an actinomorphic flower, whereas mirror images can be obtained only in one plain in zygomorphic flowers.
In an actinomorphic flower, the flower parts are equal in size, whereas in zygomorphic flowers, the flower parts are unequal in size.
Some examples of actinomorphic flowers include butter cups, lilies, tulips, and roses, while orchids and snapdragons are examples of zygomorphic flowers.
In brief, actinomorphic and zygomorphic flowers are two types of flowers that are identified according to floral symmetry. The main difference between actinomorphic and zygomorphic flower is that actinomorphic flower is radially symmetrical, whereas zygomorphic flower is bilaterally symmetrical.
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