How Many Different Amino Acids Are Used to Build Proteins

question 60

Multiple Choice

How many different amino acids are used to build proteins?

• A) 90
• B) 20
• C) 19
• D) 4

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Definitions:

Chorionic Villi

Microscopic, finger-like projections that emerge from the chorion to provide nutrient transfer from maternal blood to the fetus.

Amniotic Cavity

The fluid-filled space between the embryo or fetus and the amniotic sac, providing protection and facilitating movement.

Gastrulation

A phase early in the embryonic development of most animals, during which the single-layered blastula is reorganized into a multilayered structure known as the gastrula.

Germ Layers

The three primary layers of cells (ectoderm, mesoderm, and endoderm) in the early embryo that give rise to all organs and tissues in the body.