ISSN:
1615-6102
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
Notizen:
Summary The vacuoles of the sieve elements ofSelaginella kraussiana contain a crystalline protein which appears to degenerate in mature cells. Although it occurs in sieve elements we have elected not to call it “P-protein” because of ontogenetic and possibly functional differences between the two. The nucleus undergoes unique structural changes during development of the sieve element, ultimately being converted to a mass of tubules. The structures referred to by earlier workers as “refractive spherules” inSelaginella are probably plastids. As the size of the sieve pores in lateral and end walls falls into the same size range, the sieve elements ofSelaginella kraussiana can be considered to be sieve cells.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF01281524
Permalink
