Central hollow space inside most long bones. intervertebral discs medullary cavity lacunae

## Step 1<br />The question is asking for the term that describes the central hollow space inside most long bones. This is a terminological question in the field of anatomy, specifically related to the skeletal system.<br /><br />## Step 2<br />The options provided are "intervertebral discs", "medullary cavity", and "lacunae". Each of these terms refers to a different part of the skeletal system.<br /><br />## Step 3<br />"Intervertebral discs" are the shock-absorbing pads located between the vertebrae in the spine. They are not located inside long bones.<br /><br />## Step 4<br />"Lacunae" are small spaces within hard bone tissue where bone cells, also known as osteocytes, reside. However, these are not the central hollow space inside long bones.<br /><br />## Step 5<br />The "medullary cavity" is the central hollow space inside most long bones. It is surrounded by compact bone and contains the bone marrow.