The Egg Sack, roughly the size of a bird's egg, is able to sense the proximity of potential hosts, spewing a cloud of microscopic, insect-like spores called Motes into the air. The motes are able to group together, instinctively invading the host's body through open orifices, ultimately resulting in the gestation of a Bloodburster.
The Egg sack is generally considered to be the first stage in the life cycle of the Neomorph species, and closely resembles the Glostrido tetani and Euniceral pathogenic fungi native to Planet 4.
BG-386 was a warm but barren planet when first discovered by Weyland-Yutani. The planet was first colonized by the Yautja (Predator), who used it as a sacred hunting ground where they would breed and stalk Xenomorphs.
Jonesy, also referred as Jones, was a cat, more specifically a Ginger Tom, kept aboard the USCSS Nostromo as Ellen Ripley's pet. While the cat's official purpose was to control rodents aboard the ship, it also served as a source of relaxation and entertainment for the crew.
Jonesy and Ripley were the only two to survive the Nostromo incident caused by a Xenomorph and the ship's subsequent destruction.
Weyland-Yutani is a large conglomerate corporation known as "The Company." It is one of the corporations that runs the human colonies outside the solar system through the Extrasolar Colonization Administration, has a seat in the Interstellar Commerce Commission's Company Review Board, and also has a large presence on Earth. They hold their main offices in Tokyo, San Francisco, The Sea of Tranquility, and Thedeus.
Weyland-Yutani consistently exhibits the worst aspects of corporate profiteering, willing to sacrifice decency and human life in seemingly the pursuit of profit. The corporation has consistently ordered its employees and agents to attempt to obtain living Xenomorphs so that they can be exploited as a biological weapon, without regard for their obtainers' lives.