Anatomy
This focuses on human anatomy, though every animal is similar anatomically.
Anatomy is the study of bodies and their parts. Mainly the body is split into external parts like limbs, torso, head, etc and internal which are the organs and glands for example.
A beings anatomy is an expression of their organs which is an expression of their elemental constitution.
Hence all beings are the same in a metaphysical sense like a clockwork puppet tuned or wound to different values. The fish is a water elemental expression in physical form while the bird is an airy expression of a being.
The body
Head - This is the external sensory center which contains all of the main sensory organs or the receiving organs like eyes and ears.
Torso - Upper body area that starts around from the upper abdominal region to the neck. It contains circulatory organs and ones that deal with breathing. It is like a barrel or cylinder in its structure. The upper area is considered spiritual while the lower is more physical.
Pelvic region - Below the naval and to the hips is the pelvic region which has your sexual and excretory organs. The digestive organs sit above it. This region acts like a bowl or carrier for the body. The male genitals are considered an external organ while the female are an internal.
Arms - Arms are the major manipulators of the body. They allow you to access the world. They are made up of limbs, joints and hands.
Legs - They allow you to stand, move, sit and control your body in its direction and angle. They are made up of limbs, joints and feet.
Organs and glands
Sensory - The brain, ears, eyes, nose, mouth, skin, nerves and hair are the main sensory organs. These allow you to experience reality, to hear or see it, smell or taste and touch it.
Spiritual - The heart, lungs and throat are the main spiritual organs. These circulate nutrients and fluids or work with gasses in the body. The throat forms air into sound in order to speak.
Digestive - Our stomach, liver, spleen, pancreas, intestines and kidneys all help to process food and drink as well as producing their own special essences to help the body.
Reproductive organs - The gonads, genitals, prostate, womb and urinary system all function in a way to allow for the creation of children for animals. Their essences aid in child growth, regeneration of the body and hormonal or defining male and female traits.
Excretory - The bowels act as a physical outpass for the body. The bowels seem to give grounding and stability to the body.
Other systems
Bones - These are hard, stone like objects which are at the center of limbs or in the torso and pelvis. They act as a structure for the body to build around it.
Muscles - These are fleshy fibrous parts of the body that form around bones and act as protection as well as a contractive part which lets you move.
Tendons are around the ends of muscles usually. These are kind of like plastic cords that attach themselves to the bones or other areas.
Fat - Fat is squishy and like jelly or hard when cold. It is rendered down to make lard. This seems to act as a nutrient storage, cold protection, physical protection and other features. It is below the skin and above the muscles.
Females are fat dominant while men are muscle dominant, usually.
Skin - This covers the body in a thickened flesh in order to protect it.
Nerves - These are like power cables or sensors in the body. They allow for feelings like pain or pleasure. They animate the rest of our body electrochemcially. The spinal cord is the major nerve in the back of the body protected by bone and it connects to the brain which is the major nervous system organ.
Veins and arteries - This is the bodies circulatory system. It channels nutrients in the form of blood, an oxygenated liquid which heals the body and allows it to recoagulate to repair its self. The heart is the main organ for this system.