Table of Contents
Which plants have flagellated sperm?
The only extant seed plants that have flagellated sperm are Ginkgo and Cycadales (Table 1, Figs.
Do ferns have flagellated male gametes?
In the ferns and their allies, the sperm are flagellated, but archegonia and antheridia are at or below ground level and generally very close together. Some gymnosperms retain sperm motility, but swimming is internal.
What type of sperm do ferns have?
The sex organs of ferns are of two types. The sperm-producing organ, the antheridium, consists of a jacket of sterile cells with sperm-producing cells inside. Antheridia may be sunken (as in the families Ophioglossaceae and Marattiaceae) or protruding.
Do all plants produce flagellated sperm?
The whole ovule develops into a seed. While some primitive gymnosperms have flagellated sperm cells, the sperm in most gymnosperms and all angiosperms lack flagella. In seed plants, the use of resistant, far-traveling, airborne pollen to bring gametes together is a terrestrial adaptation.
What is a flagellated sperm?
Motile sperm cells typically move via flagella and require a water medium in order to swim toward the egg for fertilization. The sperm cells are the only flagellated cells in the life cycle of these plants. In many ferns and lycophytes, cycads and ginkgo they are multi-flagellated (carrying more than one flagellum).
Is Moss sperm flagellated?
Primitive bryophytes like mosses and liverworts are so small that they can rely on diffusion to move water in and out of the plant. Their flagellated sperm must swim through water to reach the egg. So mosses and liverworts are restricted to moist habitats.
Why do ferns have flagellated sperm?
Like nonvascular plants, ferns also have flagellated sperm that must swim to the egg. Unlike nonvascular plants, once fertilization takes place, the gametophyte will die, and the sporophyte will live independently. In ferns, the sporophyte is dominant and produces spores that germinate into a heart-shaped gametophyte.
What is the life cycle of fern?
The life cycle of the fern has two different stages; sporophyte, which releases spores, and gametophyte, which releases gametes. Gametophyte plants are haploid, sporophyte plants diploid. This type of life cycle is called alternation of generations.