Ferns Edit. In most ferns, gametophyte is a photosynthetic free living organism called a prothallus. For example, in the leptosporangiate fern Dryopteris, the gametophyte is a free-living, autotrophic prothallus that produces gametes and maintains the sporophyte during its early multicellular development.
It is therefore an object of the present invention to provide a gyro stabilized center tracking vehicle, of reduced complexity in which the gyro Spin axis is maintained in its normal position by forces reacting against the earth, and in which these forces are minimized by torquing the gyro frame about its pivot axis.nother object of the invention is to provide a gyro stabilized center-tracking trail vehicle in which a gravity sensitive mass applies a torque to the gyro frame in a direction to erect the vehicle upon tilt from a vertical or plumb line attitude.
resistance path that connects to the earth. This prevents the buildup of voltages that could cause an electrical accident. Grounding is normally a secondary protective measure to protect against electric shock. It will substantially reduce the risk of injury or death in case of shock, especially when used in combination with other electrical safety measures. An equipment ground helps protect the equipment operator. It furnishes a second path for the current to pass through from the tool or machine to the ground. This additional ground safeguards the operator if a malfunction causes the toolâs metal frame to become energized. The resulting flow of current may activate the circuit protection devices.