Question

Choose the incorrect pairs. \[ \begin{aligned} \text{I. Protandry} &- \text{Datura} \\ \text{II. Herkogamy} &- \text{Gloriosa}\\ \text{III. Self sterility} &- \text{Abutilon} \\ \text{IV. Protogyny} &- \text{Sunflower} \end{aligned} \]

• A. I and II
• B. I and IV
• C. II and III
• D. III and IV

Hint:

Sunflower is a classic example of Protandry, not Protogyny.

Answer 1

The Correct Option is D

Concept: Flowering plants exhibit various outbreeding devices that prevent self-pollination and promote cross-pollination.

Step 1: Protandry -- Datura.
In protandry, anthers mature before stigma. Datura is a common example. Hence Pair I is correct.

Step 2: Herkogamy -- Gloriosa.
Herkogamy involves spatial separation of anthers and stigma. Gloriosa exhibits herkogamy. Hence Pair II is correct.

Step 3: Self sterility -- Abutilon.
Abutilon is not a standard example of self-sterility. Therefore Pair III is incorrect.

Step 4: Protogyny -- Sunflower.
Sunflower generally shows: \[ \boxed{\text{Protandry}} \] not protogyny. Hence Pair IV is incorrect. Thus incorrect pairs are: \[ \boxed{\text{III and IV}} \] Hence option (D) is correct.