Question

Which of the following flowers is actinomorphic?
A. Pisum
B. Canna
C. Hibiscus
D. None of the above

Answer 1

Hint: Any type of cut through the centre of an actinomorphic flower will divide the flower into two equal parts.

Complete answer:
To solve this question, at first, we have to know the property of an actinomorphic flower. The main characteristic feature of an actinomorphic flower is the radial symmetry that means it can be divided into more than two identical parts by cutting through the centre. Typically each part may contain a tepal or a petal and a sepal and so on. Actinomorphic flowers are also called regular flowers or radially symmetrical flowers.
In the given options -
A Pisum flower can't be divided into two equal parts except cutting longitudinally through only one side. So, it is not an actinomorphic flower. It is a zygomorphic flower i.e, bilateral symmetry is found. Pisum belongs to the family Fabaceae and all the members of Fabaceae bear zygomorphic flowers only.
Now, the Canna belongs to the family Cannaceae. It is also a zygomorphic flower, i.e, irregular, asymmetrical flowers. It has three sepals and three petals and arranged spirally. So, it can not be divided into two equal parts cutting vertically through any plane. That is why it is not an actinomorphic flower.
The Hibiscus belongs to the family Malvaceae. This flower can be bisected into two equal parts by any plane. So, Hibiscus is an actinomorphic flower.

Thus, the right answer is option C. i.e., Hibiscus.

Note: Zygomorphic flowers also can be divided into two equal halves but through the division in one plane.