Growth and Ossification of Long Bones
MUSCLES Characteristically, all living cells, including protozoa and slime molds, contain the contractile proteins actin and myosin. Thus, actin and myosin are present in all the cells of the human…
Secondary Osteon (Haversian System)
Restriction of joint motion by permanent paralysis early in development can result in the loss of the joint cavity by having a permanent fusion occur between the apposed surfaces of…
Changes in Position of Limbs Before Birth; Precartilage Mesenchymal Cell Concentrations of Appendicular Skeleton at 6 Weeks
During the first 3 or 4 years after birth, almost all the bones of the body contain hematopoietic marrow, although regression of hematopoiesis begins in the distal phalanges of the…
Differentiation of Somites into Myotomes, Sclerotomes, and Dermatomes
The clustering of sclerotomal cells to form the bodies of the vertebrae establishes intervertebral fissures that fill with mesenchymal cells to become the intervertebral discs (see Plate 1-3). The notochord…
Initial Bone Formation in Mesenchyme; Early Stages of Flat Bone Formation
Articular cartilage, especially that found in weightbearing joints, is uniquely structured to withstand tremendous abuse. It can resist crushing by static loads considerably greater than those required to break a…
Changes in Ventral Dermatome Pattern During Limb Development
The myeloid, or bone marrow, period of hematopoiesis begins during the fourth month. The bone marrow is the principal site of all blood cell formation during the last 3 months…
Skeleton of Full-Term Newborn
Although bone remodeling begins during the fetal period, it is not very active before birth but accelerates during the first year after birth. The annual rate of bone renewal during…
Fate of Body, Costal Process, and Neural Arch Components of Vertebral Column, With Sites and Time of Appearance of Ossification Centers
Once the appendicular skeleton starts to develop, the progress is rapid. Early in the sixth week, only vague concentrations of mesenchyme represent the primordia of future bones. By the end…
Early Development of Skull
BONE GROWTH Cartilage grows continually on the side of the epiphyseal plate facing the epiphysis of a long bone, while on the opposite side of the plate facing the diaphysis,…
BONE STRUCTURE AND FUNCTION IN NORMAL AND DISEASE STATES
5 BONE STRUCTURE AND FUNCTION IN NORMAL AND DISEASE STATES Philip Sambrook Chapter objectives After studying this chapter you should be able to: 1. Understand normal bone structure and function including…
