what is the relationship between the enteric and the autonomic nervous system
Enteric nervous system The enteric nervous system (ENS) or intrinsic nervous system is one of the main divisions of the autonomic nervous system and consists of a mesh-like system of neurons that governs the function of the gastrointestinal tract.[1] It is capable of acting independent of the sympathetic and parasympathetic nervous systems, although it may be influenced by them. The ENS is also called the second brain.[2][3]
Sympathetic nervous system The target synapse of the postganglionic neuron is mediated by adrenergic receptors and is activated by either norepinephrine (noradrenaline) or epinephrine (adrenaline).
Tendon Tendons are similar to ligaments; both are made of collagen. Ligaments join one bone to another bone, while tendons connect muscle to bone.
Vein Veins are less muscular than arteries and are often closer to the skin. There are valves in most veins to prevent backflow.