Final answer:
A plane that divides an animal into equal right and left portions is known as the midsagittal plane, an important anatomical reference for both study and surgery.
Step-by-step explanation:
The surgical incision for a splenectomy could be: a) Midline, b) Pfannenstiel, c) Chevron, d) McBurney. But to address the sample question: A plane that divides an animal into equal right and left portions is b. midsagittal.
The midsagittal plane is an anatomical boundary that runs longitudinally through the body, dividing it into two equal symmetrical halves with a right and a left side. This contrasts with other anatomical planes such as the coronal plane, which divides the body into front (anterior) and back (posterior) portions, and the transverse plane, which divides the body into upper (superior) and lower (inferior) portions. The midsagittal plane is commonly used in both anatomical study and surgical procedures as a reference point.