Question

A flower has 10 stamens each having bilobed dithecous anther. If each microsporangium has 5 pollen mother cells, how many pollen grains would be produced by the flower ?

• A. 1600
• B. 200
• C. 400
• D. 800

Answer 1

The Correct Option is D

Here's the step-by-step solution:

1. Identify the given information:
   • Number of stamens in the flower = 10
   • Structure of each anther = Bilobed and dithecous
   • Number of Pollen Mother Cells (PMCs) per microsporangium = 5
2. Determine the number of microsporangia per anther:
   • A bilobed anther has 2 lobes.
   • A dithecous anther means each lobe has 2 thecae (microsporangia).
   • Therefore, the number of microsporangia in one anther = \( 2 \text{ lobes} \times 2 \text{ microsporangia/lobe} = 4 \) microsporangia.
3. Calculate the total number of microsporangia in the flower:
   • The flower has 10 stamens, and each stamen has one anther.
   • Total microsporangia = (Number of stamens) \( \times \) (Microsporangia per anther)
   • Total microsporangia = \( 10 \times 4 = 40 \) microsporangia.
4. Calculate the total number of Pollen Mother Cells (PMCs) in the flower:
   • Each microsporangium contains 5 PMCs.
   • Total PMCs = (Total microsporangia) \( \times \) (PMCs per microsporangium)
   • Total PMCs = \( 40 \times 5 = 200 \) PMCs.
5. Determine the number of pollen grains produced per PMC:
   • Each Pollen Mother Cell (PMC) is diploid and undergoes meiosis to produce 4 haploid microspores (pollen grains).
   • Pollen grains produced per PMC = 4.
6. Calculate the total number of pollen grains produced by the flower:
   • Total pollen grains = (Total number of PMCs) \( \times \) (Pollen grains produced per PMC)
   • Total pollen grains = \( 200 \times 4 = 800 \) pollen grains.

Therefore, the total number of pollen grains produced by the flower is 800.

The correct answer is (D) : 800.

Answer 2

The correct answer is: (D) 800.

Let's go through the calculations step by step to ensure accuracy:

• 1. Number of microsporangia per stamen: Since each anther has 2 lobes, and each lobe contains 2 microsporangia, each stamen has 2 × 2 = 4 microsporangia.
• 2. Total number of microsporangia in the flower: With 10 stamens, the total number of microsporangia is 10 × 4 = 40 microsporangia.
• 3. Total number of pollen mother cells: Since each microsporangium has 5 pollen mother cells, the total number of pollen mother cells is 40 × 5 = 200 pollen mother cells.
• 4. Total number of pollen grains: Each pollen mother cell produces 4 pollen grains, so the total number of pollen grains produced is 200 × 4 = 800 pollen grains.

Thus, the flower would produce 800 pollen grains.