Multiple choice

The growth of pollen tube towards ovule is due to

  1. geotropism

  2. thigmotropism

  3. chemotropism

  4. hydrotropism

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The growth of a pollen tube toward the ovule is an example of chemotropism - movement in response to chemical stimuli. The ovule releases chemical signals (specifically calcium ions and chemotropic factors like LURE peptides) that guide the pollen tube's growth. This ensures precise delivery of sperm cells to the embryo sac for fertilization.