Estimate how many sperm are produced by one antheridium. Each sperm is small, composed largely of an elongated nucleus with only a thin layer of cytoplasm, and is biflagellate. Sperm will be shed from the antheridium only when water is available. Similarly dissect part of an archegonial head and observe the characteristics of an archegonium. Prepared slides having longisections of an archegonial head show pieces of the archegonia and only rarely a complete one.
Sections do help to understand the structure, however.
Above this is a ventral canal cell then a long row of neck canal cells. At the time the egg is mature, and if water is available, the neck opens at the outer end, neck canal and ventral canal cells disintegrate, and one to several sperm swim down the neck to the egg which is fertilized by only one of the sperm. The zygote remains within the archegonium and starts developing almost immediately. The stalk elongates considerably, raising the capsule well above the top of the leafy shoot. There are some chloroplasts in the capsule wall and a few stomata occur in the epidermis of the basal portion, so it can make its own food.