Joints and Skeletal Movement
The point at which two or more bones meet is called a joint, or articulation. Joints are responsible for movement, such as the movement of limbs, and stability, such as the stability…
Growth of Bone
Long bones continue to lengthen, potentially until adolescence, through the addition of bone tissue at the epiphyseal plate. They also increase in width through appositional growth. Lengthening of Long Bones…
Intramembranous & Endochondral Ossification
Intramembranous ossification Intramembranous ossification is the process of bone development from fibrous membranes. It is involved in the formation of the flat bones of the skull, the mandible, and the clavicles.…
Bone Tissue
Bones are considered organs because they contain various types of tissue, such as blood, connective tissue, nerves, and bone tissue. Osteocytes, the living cells of bone tissue, form the mineral…
The Musculoskeletal System
Figure 19.1. Improvements in the design of prostheses have allowed for a wider range of activities in recipients. (credit: modification of work by Stuart Grout) Introduction The muscular and skeletal…
Organs with Secondary Endocrine Functions
There are several organs whose primary functions are non-endocrine but that also possess endocrine functions. These include the heart, kidneys, intestines, thymus, gonads, and adipose tissue. The heart possesses endocrine…
Endocrine Glands
Both the endocrine and nervous systems use chemical signals to communicate and regulate the body’s physiology. The endocrine system releases hormones that act on target cells to regulate development, growth,…
Regulation of Hormone Production
Hormone production and release are primarily controlled by negative feedback. In negative feedback systems, a stimulus elicits the release of a substance; once the substance reaches a certain level, it…
Hormonal Control of Blood Calcium Levels
Regulation of blood calcium concentrations is important for generation of muscle contractions and nerve impulses, which are electrically stimulated. If calcium levels get too high, membrane permeability to sodium decreases…
Hormonal Regulation of Metabolism
Blood glucose levels vary widely over the course of a day as periods of food consumption alternate with periods of fasting. Insulin and glucagon are the two hormones primarily responsible…
