Question

Arrange the following commercial crops in ascending order with respect to their ploidy level
(A). Wheat
(B). Cotton
(C). Tomato
(D). Banana
Choose the correct answer from the options given below:

• A. (D), (C), (A) and (B)
• B. (C), (D), (A) and (B)
• C. (C), (D), (B) and (A)
• D. (D), (C), (B) and (A)

Hint:

To remember: Tomato is a standard diploid (\(2x\)), commercial banana is a seedless triploid (\(3x\)), upland cotton is an allotetraploid (\(4x\)), and bread wheat is an allohexaploid (\(6x\)).

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Ploidy level refers to the number of complete sets of chromosomes in a cell.
Crops can be diploid (\(2x\)), triploid (\(3x\)), tetraploid (\(4x\)), hexaploid (\(6x\)), or have higher levels of polyploidy, which is common in domesticated crop species.

Step 2: Detailed Explanation:
Let us identify the ploidy levels of the listed commercial crops:
- Tomato (Solanum lycopersicum):
Tomato is a diploid species with a basic chromosome number of \(x = 12\).
Its somatic cells contain two sets of chromosomes (\(2n = 2x = 24\)).
Ploidy level = Diploid (2).
- Banana (Musa acuminata):
Most cultivated commercial bananas (such as 'Cavendish') are seedless triploids with a basic chromosome number of \(x = 11\).
Their somatic cells contain three sets of chromosomes (\(2n = 3x = 33\)).
Ploidy level = Triploid (3).
- Cotton (Gossypium hirsutum):
Cultivated Upland cotton is an allotetraploid species with a basic chromosome number of \(x = 13\).
Its somatic cells contain four sets of chromosomes (\(2n = 4x = 52\)).
Ploidy level = Tetraploid (4).
- Wheat (Triticum aestivum):
Common bread wheat is an allohexaploid species with a basic chromosome number of \(x = 7\).
Its somatic cells contain six sets of chromosomes (\(2n = 6x = 42\)).
Ploidy level = Hexaploid (6).
Arranging these crops in ascending order of their ploidy level:
Tomato (C, diploid) \(<\) Banana (D, triploid) \(<\) Cotton (B, tetraploid) \(<\) Wheat (A, hexaploid).
This sequence is represented as: (C), (D), (B) and (A).

Step 3: Final Answer:
Hence, the correct option is (C).