In a chemical reaction, the chemicals you start with (those in the rectangle) are called . The ones you end up with (in the circle) are called .

one would be wind another would be water density

b - the respond is innate and varies over time.

good luck!

answer : haversian

[explanation: -(compact bone is organized as parallel columns, known as haversian systems, which run lengthwise down the axis of long bones. these columns are composed of lamellae, concentric rings of bone, surrounding a central channel, or haversian canal, that contains the nerves, blood vessels, and lymphatic system of the bone)]