Iris color is determined by the amount of brown melanin pigment in the posterior (back) of the iris, whether blue, green or brown, and the occasional golden hue is iris stroma or muscle overlying. Heterochromia is a color difference between eyes. Since you only show one, I canât tell.
Definition of Distal. Distal: The more (or most) distant of two (or more) things. For example, the distal end of the femur (the thigh bone) is the end down by the knee; the end more distant from the torso. The distal bile duct is the far end of the cystic duct, the end away from the gallbladder. And the distal lymph node in a chain of nodes is the most distant one.
Proximal and distal. Proximal refers to the end of a structure nearest a major point of reference and distal to the end furthest from a point of reference. The point of reference is usually the origin of a structure (such as a limb) or the ventral midline of the body. Proximal and distal are relative terms.These terms are correctly used to describe relative positions of structures in the limbs. Medial and lateral.ranial refers to the head end and caudal to the tail end. Anterior and posterior. In a quadruped the terms are synonymous with cranial and caudal. In a biped (Homo) anterior is used to indicate the ventral surface and posterior to indicate the dorsal surface.