Question

Which of the following placentation is found in the family Fabaceae?
A. Axile
B. Marginal
C. Parietal
D. Basal

Answer 1

Hint: Inside the ovary of a flower, the arrangement of the placenta is known as placentation. The placenta is the structure that helps in attaching the ovules to the walls of the ovary.
Complete step-by-step answer:

Before jumping into the correct answer, let’s have a detailed look at the options and understand them.

- Axile placentation- In this specific type of arrangement, the ovules arise from the placental tissue, which is derived from the apices of the septa of a locule i.e. the placenta are arranged along the axis of the ovary.
- Marginal placentation- As the name suggests, in this type of placentation, the placenta is arranged along the margins or border of the ovary. The ovules develop in two separate rows in this type of placentation.
- Parietal placentation- In this particular type of placentation, the ovules develop inside the ovary and are attached to the inner wall of the ovary. The ovary here is truly one-chambered but due to the formation of a false septum, it becomes two-chambered.
- Basal Placentation- In this type of placental arrangement, the placenta is arranged at the base of the ovary.
Now, as we know, the family Fabaceae or the Leguminosae family consists of peas, beans, or legumes. The seeds of this family as we use them in day-to-day lives are observed to be lying on the margins of the pods in which they are found. Hence, they show a marginal type of arrangement of the placenta.

Hence, the correct answer is option (B).

Note: Leguminosae family members are important agricultural plants. Humankind is known to cultivate legumes since ancient times. Legumes are an important source of protein in human and animal diets. Legumes, as a matter of fact, cannot fixate their own nitrogen and are dependent on nitrogen-fixing bacteria that form nodules in their roots and both of them show symbiosis.