Target Exam

CUET

Subject

Biology

Chapter

Sexual Reproduction in Flowering Plants

Question:

How many cells are located at the chalazal end of the embryo sac?

Options:

One

Two

Three

Four

Correct Answer:

Three

Explanation:

The correct answer is Option (3) →Three

Explanation:

  • In a mature embryo sac (female gametophyte) of an angiosperm, there are seven cells and eight nuclei.
  • The chalazal end of the embryo sac contains three antipodal cells, which are non-functional and eventually degenerate.

Cellular arrangement in the embryo sac:

  1. Micropylar endEgg apparatus (3 cells)
    • One egg cell
    • Two synergids (assist in pollen tube guidance)
  2. Central cell → Contains two polar nuclei, which fuse with a sperm cell to form endosperm (3n).
  3. Chalazal endThree antipodal cells

Other options:

One – Incorrect, because there are three antipodal cells at the chalazal end.

Two – Incorrect, because the chalazal end has three cells, not two.

Four – Incorrect, because only three cells