The key difference between acropetal and basipetal order is that in acropetal order, new flowers are present at the apex while in basipetal order, new flowers are present at the base or bottom of the inflorescence.
Inflorescence is a cluster of flowers arranged on a stem. Racemose inflorescence and cymose inflorescence are two types of inflorescences. In racemose inflorescence, flowers are arranged in acropetal order. In acropetal order, new flowers are seen at the apex, and older flowers are seen at the base of the inflorescence. In cymose inflorescence, flowers are arranged in basipetal order. In basipetal order, older flowers are present at the apex while younger flowers are at the base.
CONTENTS
1. Overview and Key Difference
2. What is Acropetal Order
3. What is Basipetal Order
4. Similarities Between Acropetal and Basipetal Order
5. Side by Side Comparison – Acropetal vs Basipetal Order in Tabular Form
6. Summary
What is Acropetal Order?
Acropetal order is the arrangement of older flowers at the base of the inflorescence while new flowers arise at the apex of the inflorescence. Therefore, new flowers and buds can be seen at the top of the inflorescence. Moreover, younger flowers are present towards the centre of the inflorescence while older flowers are present towards the outside.
Figure 01: Acropetal Order
The formation of flowers is indefinite or unrestricted in racemose inflorescences. This is because the main axis continues to grow.
What is Basipetal Order?
Basipetal order is the arrangement of older flowers at the apex and new flowers and buds at the base. Inflorescence main axis terminates in flower, typically the oldest flower. Therefore, the formation of flowers is definite or restricted.
Figure 02: Basipetal Order
Basipetal order is the opposite of acropetal order. Older flowers are present towards the centre while new flowers are present towards the periphery. Cymose inflorescence shows basipetal order. Basipetal order is clearly visible in biparous and multiparous cymose inflorescences.
What are the Similarities Between Acropetal and Basipetal Order?
- Acropetal and basipetal order are two types of flower arrangements in the inflorescence.
- Basipetal order is the opposite arrangement of acropetal order.
- In both types, new flowers, buds and older flowers can be distinguished clearly.
- Both types of arrangements can be seen commonly in nature.
What is the Difference Between Acropetal and Basipetal Order?
Acropetal order is the arrangement of new flowers at the apex and older flowers at the base. In contrast, basipetal order is the flower arrangement in which older flowers are present at the apex while new flowers are present at the base. So, this is the key difference between acropetal and basipetal order.
Moreover, the acropetal order is seen in racemose inflorescences while basipetal order is seen in cymose inflorescences. Thus, this is also a significant difference between acropetal and basipetal order. Furthermore, the main axis of the racemose inflorescence continues to grow. Hence, flower formation is indefinite or unrestricted. But, the main axis of the cymose inflorescence terminates in flower. Hence, they show limited growth.
The following table tabulates more differences between acropetal and basipetal order.
Summary – Acropetal vs Basipetal Order
Racemose and cymose are two main types of inflorescences. In racemose inflorescence, flowers are arranged in acropetal order. In acropetal order, new flowers are present at the apex while older flowers are present at the base. On the other hand, in cymose inflorescence, flowers are arranged in basipetal order. Basipetal order is the opposite arrangement of acropetal order. In basipetal order, the main axis of the inflorescence terminates in a flower. Older flowers are present at the apex while new flowers are present at the base. Thus, this summarizes the difference between acropetal and basipetal order.
Reference:
1. “Racemose And Cymose Inflorescence | Botany”. Biology Discussion, 2020, Available here.