BIO 106 Lecture Notes - Lecture 18: Bone Remodeling, Parathyroid Gland, Osteoporosis
Document Summary
Rotation: moving around a certain point, on an axis. Circumduction: movement of ball and socket joint, wide range of mobility. Eversion: sole of foot turned outward, pigeon-toed. Mature bone cells that maintain bone structure derived from osteoblasts. Starting with some certain material and replacing it with bone. Bone development between sheets of fibrous connective tissue. Osteoblasts/osteocytes come in to help assist in the building of bone. Cartilage replaced by bone, used by most bones. As bones lengthen, joints increase in size. Taking nutrients from the bone and diffusing them into the proliferating zone where cells diverge and grow. Occurs until one is approximately 27-30 years old. Vitamin d converted to hormone that allows calcium absorption in intestine. Growth hormone (gh) stimulates general bone growth/epiphyseal plates. Sex hormones increase growth, estrogen and testosterone. Pth (targets intestines and parathyroid system) increases blood calcium by accelerating bone recycling. Bones weakened due to decreased bone mass. Bone reabsorption exceeds absorption around age 40.
