Wall ingrowths in the jacket cells of the antheridia ofAnthoceros laevisL.

Abstract

As the antheridia of Anthoceros near maturity, wall ingrowths develop along the inner faces of the jacket cells. These cells contain numerous mitochondria and abundant rough endoplasmic reticulum (ER) thus resembling transfer cells described previously from a variety of other anatomical situations. Microbodies, hitherto undescribed in the gametophyte of Anthoceros, also occur in the jacket cells. Since ER and ribosomes are absent from the nearly mature spermatocytes of Anthoceros, production of proteins for the final stages in their development is considered to be a likely function of the jacket cells. The increase in surface area of the cell membrane, brought about by the wall ingrowths, may be an adaptation to facilitate transport of such materials from the jacket cells. Wall ingrowth development may also be related to the retrieval of excess carbohydrate from the maturing spermatocytes. In addition it is suggested that the wall thickenings in the jacket cells of Anthoceros may playa part in the spermatozoid dissemination mechanism.