Jeiunum. Part of small intestine succeeding duodenum and preceding ileum in mammals. Main absorptive region. Larger diameter and larger villi than rest of small intestine.
Joint. The point of contact between two (or more bones, together with the tissues surrounded it. Joints into three classes that differ in the degree of freedom of movement they allow:
(1) Immovable joints, e.g. the sutures between the bones that from the cranium:
(2) Slightly movable joints, e.g. the symphyses between the vertebrae of the spinal column; and
(3) feely movable or synovial joints e.g. those that occur between the limb bones.
Jugular. Main vein returning blood from head (particularly brain) in vertebrates. See cardinal Veins.
Junior homonym. The more recently published of two or more identical names for the same or different taxa.
