Circulatory System – General Aspects. In small invertebrate organisms, no circulatory system is necessary, as diffusion distances are short.
Fig 12.2 – Blood pressure and cross-sectional areas of the different vessels of the blood vascular system.
Fig 12.11 – Basic vertebrate blood vascular system circulation, as illustrated in a shark
Neutrophil (a WBC)
Arrows = adipose cells
Arrows = developing blood cells
Fig 12.49 – Lymphatic system in a salamander. Note the prominence of the lymph hearts for moving lymph within the lymphatic system.
Fig 12.47 – Lymphatic circulation and lymph nodes