What to Pack for the San Francisco Weather in July. While most people come packed for warm, sunny days, I recommend coming with a few long sleeved items so you have something to keep you warm as the evenings cool down. For the San Francisco weather in July, I typically wear short sleeved shirts and pants during the day. You could probably bring along some shorts too. Since it's breezy here in July, you will find it a bit too cool most of the time for shorts.
Bone marrow is the soft, flexible connective tissue within bone cavities. A component of the lymphatic system, bone marrow functions primarily to produce blood cells and to store fat. Red marrow contains hematopoietic stem cells that produce two other types of stem cells: myeloid stem cells and lymphoid stem cells. 2  These cells develop into red blood cells, white blood cells, or platelets.
The most important function of the skeleton is the production of blood cells. Some of the bones in the human body are filled with bone marrow, a substance that produces red and white blood cells. The blood cells produced by the bone marrow are crucial because red blood cells provide oxygen to the body, and white blood cells are essential for fighting infection and maintaining the immune system.