Which of These Species Has the Largest Average Brain Size

question 21

Multiple Choice

Which of these species has the largest average brain size (measured in cubic centimeters) ?

• A) Homo sapiens
• B) Homo habilis
• C) Pan troglodytes
• D) Sahelanthropus tchadensis

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Definitions:

Spinal Cord

A long, thin, tubular structure made up of nervous tissue, which extends from the brainstem down the back, enclosed in the spinal canal.

Filum Terminale

A fibrous tissue extension of the conus medullaris of the spinal cord, anchoring it within the vertebral canal.

Conus Medullaris

The tapered, lower end of the spinal cord which typically ends at the first or second lumbar vertebra, marking the transition from spinal cord to cauda equina.

Lateral Funiculus

A bundle of nerve fibers along the lateral side of the spinal cord, important in sensory and motor function.