Before eight weeks, the skeleton of the human embryo is composed of __________.

• A. lamellar bone
• B. fibrous membrane
• C. spongy bone
• D. compact bone

Answer: (B)

Verified step by step guidance

1. Understand that the human embryo's skeleton initially forms from a different material than adult bone. This is crucial for early development.
2. Recognize that before eight weeks, the embryonic skeleton is not yet ossified and is composed of a softer, more flexible material.
3. Identify the types of materials that can form the early skeleton: fibrous membranes and cartilage are common precursors to bone.
4. Note that fibrous membranes are a key component in the formation of flat bones through a process called intramembranous ossification.
5. Conclude that before eight weeks, the human embryo's skeleton is composed of fibrous membranes, which later ossify to form bone.