Science / Spiders / Tracheae: The air tubes in insects: in spiders, tubular respiratory organs of different origin: by many thought to be modified book lungs. MORE
Science / Biology / Heart: The multicellular, chambered, muscular structure that pumps blood through the circulatory system by alternately contracting and relaxing. MORE
Science / Spiders / Spiracle: The opening of the tracheae on the underside of the abdomen. MORE
Health / Disease / Hives: A skin eruption of smooth, slightly elevated areas on the skin which is redder or paler than the surrounding skin. Often attended by severe itching. Also called cynanche trachealis. In the mid-ninetee MORE