contractile tubules — (SIPUNCULA) Numerous, short and simple, or longer and branching tubules originating from the contractile vessel and extending into the body cavity; polian tubules … Dictionary of invertebrate zoology
dorsal vessel — 1. The dorsal blood vessel. 2. (SIPUNCULA) see contractile vessel … Dictionary of invertebrate zoology
polian vessel — see contractile vessel … Dictionary of invertebrate zoology
peanut worm — any small, unsegmented, marine worm of the phylum Sipuncula, that when disturbed retracts its anterior portion into the body, giving the appearance of a peanut seed. Also called sipunculid. * * * ▪ marine worm Introduction also called… … Universalium
Pseudo-heart — Pseu do heart , n. [Pseudo + heart.] (Zo[ o]l.) Any contractile vessel of invertebrates which is not of the nature of a real heart, especially one of those pertaining to the excretory system. [1913 Webster] … The Collaborative International Dictionary of English
compensatory sac — see contractile vessel … Dictionary of invertebrate zoology
circulation — circulable /serr kyeuh leuh beuhl/, adj. /serr kyeuh lay sheuhn/, n. 1. an act or instance of circulating, moving in a circle or circuit, or flowing. 2. the continuous movement of blood through the heart and blood vessels, which is maintained… … Universalium
muscle — muscleless, adj. muscly, adj. /mus euhl/, n., v., muscled, muscling, adj. n. 1. a tissue composed of cells or fibers, the contraction of which produces movement in the body. 2. an organ, composed of muscle tissue, that contracts to produce a… … Universalium
human cardiovascular system — ▪ anatomy Introduction organ system that conveys blood through vessels to and from all parts of the body, carrying nutrients and oxygen to tissues and removing carbon dioxide and other wastes. It is a closed tubular system in which the… … Universalium
Lymphatic system — Infobox Anatomy Name = Lymphatic System Caption = An image displaying the lymphatic system.The lymphatic system in vertebrates is a network of conduits that carry a clear fluid called lymph. It also includes the lymphoid tissue through which the… … Wikipedia