Aperson is walking through a park. a branch from a tree falls, nearly hitting her. her heartbeat speeds up. which part of the nervous system was responsible for this?

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)]

b a mature ovary of a plant.