Step 1: Siddha system divides the human body into physical and vital components.
Step 2: Udal Thathukkal (Seven physical constituents) are Saaram, Senneer, Oon, Kozhuppu, Enbu, Moolai, and Sukkilam/Suronitham.
Step 3: These are considered the structural and functional basis of the human body.
Step 4: Uyir Thathukkal refers to three vital forces (Vatham, Pitham, Kabam), but Udal Thathukkal are the structural units.