Question

part b:

1. research and then compare the infant to the adult skull with respect to:

	similarities	differences in numbers of bones	differences in composition	percentage of body length
infant skull

Explanation:

To complete the table, we analyze each category:

Similarities:

Both infant and adult skulls have the same basic skull bone structure (e.g., frontal, parietal, temporal, occipital bones in the cranial cavity and facial bones like maxilla, mandible).

Differences in numbers of bones:

• Adult Skull: Cranial bones are fused (e.g., fontanelles close), so fewer distinct bones (cranial: ~8 fused, facial: ~14). Total skull bones (cranial + facial) are fewer due to fusion.
• Infant Skull: Cranial bones are unfused (fontanelles present), so more distinct bones (e.g., cranial bones like frontal are two separate bones, parietal bones are separate, with fontanelles as soft tissue gaps). Thus, more individual bones before fusion.

Differences in composition:

• Adult Skull: Bones are mostly compact bone, with fully ossified (hardened) structures. Fontanelles are closed, and bones are denser.
• Infant Skull: Bones have more cartilage and are less ossified (softer). Fontanelles (fibrous connective tissue) allow growth; cranial bones are thinner and more flexible (e.g., frontal bone is two parts, mandible is two parts).

Percentage of body length:

• Adult Skull: ~1/8 of total body length (skull is relatively smaller proportionally).
• Infant Skull: ~1/4 of total body length (skull is a larger proportion of the body at birth, as the body grows more than the skull post - birth).

Answer:

	Similarities	Differences in numbers of bones	Differences in composition	Percentage of body length
Infant Skull	Has the same basic skull bone structure (cranial and facial bone types)	More distinct bones (cranial bones unfused, e.g., frontal is two bones; fontanelles as soft tissue gaps)	More cartilage, less ossified; thinner, flexible bones; fontanelles present	~1/4 of body length