What are Pollen Sacs?

Pollen sacs are cavities in the male reproductive system, anther, which produce pollen grains. The pollen sacs contain microspore mother cells which divide to produce four haploid microspores. The microspores further form the pollen grain.

In angiosperms, there are usually four pollen sacs in each anther, whereas in gymnosperms there are a number of pollen sacs present which make up the male cone.

The pollen sacs contain a number of archesporial cells which form the microspore mother cells. At first they are tightly bound together, but later get loosely arranged to help in the release of pollen grains.

Structure

• The outermost layer is the epidermis.
• Just below the epidermis is the endothecium layer. It is also known as the fibrous layer and forms a junction between two pollen sacs.
• Inside the endothecium lies the parenchymal layers, which are 1-3 in number.
• The innermost layer is the tapetum which gives nutrition to the developing microspores.

Explore BYJU’S Biology for more.

Also see:

• Pollen Grains
• Self Pollination vs Cross Pollination