O3. Circulatory system
and blood
- O3a. Heart
- O3b. Vessels
- O3c. Blood
O9. Excretion and
osmoregulation
- O9a. Kidney
- O9b. Other excretory organs
O11. Endocrine system
- O11a. Pituitary gland
- O11b. Thyroid gland - Parathyroid glands
- O11c. Adrenal tissue
- O11d. Endocrine pancreas
- O11e. Pineal gland
O13. Sense organs
- O13a. Stato-acoustic system (inner, middle and external ear)
- O13b. Chemoreception
- O13c. Vision
- O13d. Various senses
O2. Muscle
- O2a. Skeletal muscle
- O2b. Cardiac muscle
- O2c. Visceral muscle
O4. Immune system
- O4a. Spleen
- O4b. Thymus
- O4c. Various lymphoid organs - Phagocytic system
O6. Digestive system
- O6a. Oral cavity
- O6b. Esophagus
- O6c. Stomach (proventriculus - gizzard)
- O6d. Small and large intestine - caecum
O8. Respiratory system
- O8a. Upper respiratory tract - syrinx
- O8b. Lower respiratory tract
O10. Nervous system
- O10a. Central nervous system
- O10b. Peripheral nervous system
O14. Miscellaneous -
Several organs
- O14a. Several organs, gross histology