Below, is a para-sagittal cross-section through the foot. 

Observe all the articulating bones via the shiny white cartilage present on the apposing surfaces. 

Approximately how many bones can you see in this cross-section?

Identify the spongy (trabecular/cancellous) bone components. Some obvious spongy bone is indicated by label 1. Spongy bone is composed of a network of bony struts, and filled with bone marrow.

Compact (cortical) bone is seen at the periphery of bone, and is solid, dense bone.

Bone is a highly vascular tissue: different bones of the skeleton have different amounts of blood supply.  Some, such as the bones of the toes, have abundant blood supply; some bones have a moderate blood supply, such as the tibia; while others, such as the head of the femur in the hip joint have a limited blood supply.

Bone marrow is the flexible connective tissue in the internal cavities in bones and is a major source of mesenchymal stem cells. It is comprised mainly of blood cells and adipose tissue. 

Which of the following is true of bone marrow? It contains mesenchymal stem cells which are: