Dorsal
The back or upper side (posterior in human anatomy)
Ventral
the under side (anterior in human anatomy)
Lateral/Medial
the sides, right, and left/ towards the midline
Anterior, Cephalic, or Cranial
the head end of the animal (superior in human anatomy)
Posterior or Caudal
the tail end of the animal (inferior in human anatomy)
Median
the middle
Central
the part of a system nearest the middle of the animal
Peripheral
the part nearest the surface
Proximal
nearest the origin, near the main mass of the body, as the thigh
Distal
further away from the origin, away from the main mass of the body, as the toes
Superficial
on or near the surface
Deep
some distance below the surface
Superior
on or near the surface
Deep
some distance below the surface
Superior
above/head
Inferior
below/feet
Median plane
It divides the body into two nearly identical halves, right and left.
Sagittal plane
right and left, not identical
Horizontal or Frontal
front/back
Transverse or Cross
upper/lower portion
Longitudinal or Antero/Posterior Axes
line in the median sagittal plane extending from head to tail
Sagittal or dorsoventral axes
any line in the median sagittal plane extending from dorsal to ventral surfaces
Transverse or Mediolateral
any line in the transverse plane running from side to side
Spherical
type of symmetry where there’s finite number of symmetry (round)
Radial
actinomorphic; laid out equally from a central axis (flattened) symmetry
Bilateral
only the midsagittal plane divides; single/simple symmetry
Metamerism/Segmentation
regular repetition of body parts along the anteroposterior axis.
Homonomous
segmentation of the animal body into nearly like segments
Heteronomous
various segments differ from each other to a greater or less extent
Cephalization
tendency of the anterior body to become distinctly differentiated from the body
Homologous structures
those which, however unlike in function or superficial appearance, have the same origin, as demonstrated by the study of their embryonic origin and development and their paleontological history.
Analogous structures
resemble each other either in superficial appearance or in function but have had different origins.