sporopollenin

Examples of sporopollenin in the following topics:

• Sporophytes and Gametophytes in Seedless Plants

  • The spores of seedless plants are surrounded by thick cell walls containing a tough polymer known as sporopollenin.
  • Sporopollenin is unusually resistant to chemical and biological degradation.
  • In seed plants, which use pollen to transfer the male sperm to the female egg, the toughness of sporopollenin explains the existence of well-preserved pollen fossils.
  • Sporopollenin was once thought to be an innovation of land plants; however, the green algae, Coleochaetes, also forms spores that contain sporopollenin.

• Charales

  • Green algae in the order Charales, and the coleochaetes, microscopic green algae that enclose their spores in sporopollenin, are considered the closest-living relatives of embryophytes.
  • They produce the compounds lignin and sporopollenin.

• Bryophytes

  • Some spores protected by sporopollenin have survived and are attributed to early bryophytes.

• Sexual Reproduction in Angiosperms

  • The exine contains sporopollenin, a complex waterproofing substance supplied by the tapetal cells.
  • Sporopollenin allows the pollen to survive under unfavorable conditions and to be carried by wind, water, or biological agents without undergoing damage.