What does the prefix MESO- mean?

What does the prefix MESO- mean?

• A. Middle
• B. Outer
• C. Inner
• D. Around

Answer: (A)

MESO- denotes middle. It comes from Greek mesos, meaning middle, and is used in anatomy to describe structures that lie between others or in the central position. A classic example is the mesoderm, the middle germ layer in early development, situated between the outer ectoderm and the inner endoderm and giving rise to muscles, bones, and connective tissues. This middle positioning is exactly what the prefix conveys, which is why “middle” is the best fit. In contrast, prefixes for outer or inner locations would be ecto- and endo-, and those meaning around would be peri- or circum-.

MESO- denotes middle. It comes from Greek mesos, meaning middle, and is used in anatomy to describe structures that lie between others or in the central position. A classic example is the mesoderm, the middle germ layer in early development, situated between the outer ectoderm and the inner endoderm and giving rise to muscles, bones, and connective tissues. This middle positioning is exactly what the prefix conveys, which is why “middle” is the best fit. In contrast, prefixes for outer or inner locations would be ecto- and endo-, and those meaning around would be peri- or circum-.