What is the name for the study of anatomy that focuses on each individual organ system?

The correct answer would be - systemic anatomy.

Explanation:

Systemic anatomy is one of the branches of anatomy which is the study of the bodily structures of animals, humans and other organisms as revealed by separation or dissection of individual organ systems such as the nervous system or digestive system.

It is concerned with the anatomy of the different organ systems or in other words, a system-wise study of anatomy by studying its different components one by one.

Thus, the correct answer is - systemic anatomy.

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