Chapter1

Anatomy

Terminology

• Anatomy: study of body structure• Physiology: study of how the body functions• Pathophysiology: branch of science that describes

the cnsequences of the improper functioning of the body parts

Homeostasis

• Homeostasis is the ability to maintain a relatively stable internal environment in an ever-changing outside world

• In order for internal constancy to be maintained, we need to be able to detect variation from set point

Normal range

Calcium 8 – 10 mg/dl Phosphate 3 – 4.5 mg/dlAlkaline Phosphatase 20 – 70 U/LUrea 7 – 18 mg/dl

Negative Feedback

• The stimulus and the output moving in opposite direction

• Example: Regulation of blood glucose levels

Positive Feedback

• The output enhances the original stimulus

• Example: 1. Regulation of blood clotting2. stretching of cervix →

oxytocin secretion → contraction of uterus → more stretching of cervix

• A positive feedback requires an external “break”