How long can C-Fern sperm swim?

C-Fern sperm can swim for over two hours at 25 °C in the Sperm Release Buffer (SRB) as described in the C-Fern Chemotaxis exercise – Chemical Attraction. (See also the C-Fern Manual for the formulation of SRB.) Sperm will swim a much shorter time in plain distilled water, although it is more than sufficient to […]

How big are C-Fern spores?

C-Fern spores are quite large for fern spores, about 120 µm (microns). Surprisingly, human eggs, i.e. secondary oocytes, and C-Fern spores are similar in size and shape. A vial containing 300,000 C-Fern spores (ca. 240 mg) is a graphic demonstration of the number of eggs (primary oocytes) in the ovaries of a 7-year-old girl. Only […]

Where can I obtain the C-Fern antheridiogen?

C-Fern antheridiogen, the pheromone which determines the sexual phenotype of gametophytes, can be easily harvested and used in experiments. Use old cultures of gametophytes, preferably those which are not contaminated, and carefully scrape the gametophytes from the surface. Next, freeze and then thaw the agar. The antheridiogen containing liquid will separate from the agar and […]

How do I spread out C-Fern on the agar surface?

C-Fern spores can be evenly spread in Petri dishes by using nickel-chromium wire (ca 0.64 mm) in an inoculation loop holder. Nickel-chromium wires can be repeatedly flamed to achieve surface-sterilization. This thinner wire gives superior results compared to using thicker plastic or metal spreaders. However, if you take care, thicker spreaders will work – even […]