Which type of symmetry allows a body to be divided into two equal parts by a single cut?

Bilateral symmetry is characterized by a body being divisible into two mirror-image halves along a single plane. This type of symmetry is typical in many animals, including humans, where the left and right sides can be reflected to show a balance in structure and form. Each half is a mirror image of the other, hence the term "bilateral."

In contrast, radial symmetry involves an organism being arranged around a central axis, allowing for division into multiple equal sections, which is common in organisms like starfish or jellyfish. Asymmetrical organisms lack any form of symmetry, making it impossible to divide them into equal parts, while spiral symmetry refers to a more complex arrangement often seen in some shells or flowers where parts are arranged in a spiral pattern instead of being directly reflective across a plane.

Thus, the defining characteristic of bilateral symmetry is its capacity for a single cut yielding two equal, mirrored halves.