Osteogenesis

Osteogenesis Osteogenesis is the process of laying down new bone material by osteoblasts

Intramembranous 1. Connective tissue appears at the site of the future bones.

Intramembranous 2. (Connective tissue) Enlarge and differentiate into Osteoblasts.

3. Osteoblasts begin to deposit bony matrix. Forming spongy bone.

Bone is created from osseous connective tissue Bone is created from osseous connective tissue. Like other types of connective tissue, osseous tissue is composed of relatively sparse cells surrounded by an extracellular network, or matrix. Bone matrix is a tough, resilient mixture of protein and minerals. Osteoblasts, a type of bone cell, secrete proteins into the matrix, which provide tensile strength (resistance to stretching and twisting). The principal protein of the bone matrix is collagen, which accounts for almost one-third of the dry weight of bone. Most of the rest of the bone's weight is due to the minerals of the matrix. These are mainly calcium phosphate and calcium carbonate. Embedded in the protein network, the minerals provide hardness and compressive strength.

4. Living cells on the outside of the spongy bone form the periosteum.

5. Periosteum makes compact bone. Osteoblasts Osteocytes.

Endochondrial 1. Hyaline cartilage is replaced by bone. (Starts in the diaphysis). 2. Periosteum formed and blood vessels enter. 3. Spongy (Secondary Ossification) and compact bone appear (Primary Ossification).

Epiphyseal plate 1. Cartilage cells replicate (mitosis). 2. Cells enlarge and thicken lengthening the bone. 3. Cells calcify and die.

Homeostasis Use any resource available to write down how the following things can affect bone growth: Calcium Sex Hormones Phosphorus Calcitonin Vitamin D PTH (parathyroid Horomone) Hormones Growth Hormone