Consider the following plants: 1. Groundnut 2. Horse-gram 3. Soybean How many of the above belong to the pea family?
- A.Only one
- B.Only two
- C.All three
- D.None
Correct answer
Explanation
The correct answer is C, All three. Groundnut, horse-gram and soybean are all legumes of the family Fabaceae (Leguminosae), the pea family.
Members of the pea family bear their seeds in pods and carry root nodules in which Rhizobium bacteria fix atmospheric nitrogen. That is why pulses and oilseed legumes enrich the soil and are grown in rotation with cereals. Groundnut (Arachis hypogaea) is unusual because its pods develop under the ground after the flower stalk bends into the soil. Horse-gram (Macrotyloma uniflorum), called kulthi, is a hardy dryland pulse of southern India. Soybean (Glycine max) is a leading source of protein and edible oil, grown widely in Madhya Pradesh and Maharashtra.
A is wrong: it counts only one legume, though all three are legumes.
B is wrong: no plant in the list belongs to another family, so two is too few.
D is wrong: every plant listed is a member of Fabaceae.
Exam tip: Fabaceae (pea family) = pulses, groundnut, soybean; root nodules with Rhizobium fix nitrogen.
Practice Questions
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