What is the Difference Between Pollen and Spore?

The main difference between pollen and spores lies in their origins, structure, and function. Here are the key differences:

1. Origin: Pollen grains are produced by seed plants (angiosperms and gymnosperms), while spores are produced by ferns, lycopods, horsetails, mosses, and fungi.
2. Structure: Pollen grains are multicellular reproductive structures that contain two sets of chromosomes (diploid), while spores are unicellular reproductive structures that contain only one set of chromosomes (haploid).
3. Function: Pollen grains contain the male gamete of the plant and are involved in the fertilization process, while spores are involved in both reproduction and survival in unfavorable conditions.
4. Dispersion: Pollen grains are typically dispersed by wind, water, and animals, while spores are dispersed in various ways, such as wind or water.
5. Fertilization: In seed plants, pollen grains are involved in double fertilization, where one male nucleus fuses with the egg cell nucleus to form the diploid zygote, and the other male nucleus fuses with the diploid secondary nucleus to form the triploid endosperm. In contrast, spores in seedless plants undergo a process called meiosis to produce haploid gametes for fertilization.

In summary, pollen grains are multicellular, diploid reproductive structures produced by seed plants, while spores are unicellular, haploid reproductive structures produced by various plant and fungal species. They have different functions, structures, and methods of dispersion.

Comparative Table: Pollen vs Spore

Here is a table comparing the differences between pollen and spores: