Step 1: Structure of an anther.
A typical angiosperm anther is bilobed and each lobe contains two pollen sacs. Thus, in total, an anther has four pollen sacs.
Step 2: Function of pollen sacs.
Pollen sacs are the sites of microsporogenesis, where microspore mother cells undergo meiosis to form haploid microspores (pollen grains).
Step 3: Analysis of options.
- (A) Four: Correct, because a normal anther has four pollen sacs.
- (B) Two: Incorrect, refers only to one lobe of the anther.
- (C) One: Incorrect, anther always contains multiple sacs.
- (D) Eight: Incorrect, number is not eight.
Step 4: Conclusion.
The correct answer is (A) Four, as each anther typically has four pollen sacs.
Answer the following questions:
[(i)] Explain the structure of a mature embryo sac of a typical flowering plant.
[(ii)] How is triple fusion achieved in these plants?
OR
[(i)] Describe the changes in the ovary and the uterus as induced by the changes in the level of pituitary and ovarian hormones during menstrual cycle in a human female.
Flowering plants with hermaphrodite flowers have developed many reproductive strategies to ensure cross-pollination. Study the given outbreeding devices adopted by certain flowering plants and answer the questions that follow.
Note : All plants belong to the same species. No pollen tube growth/inhibition of pollen germination on stigma. Pollen germination on stigma.