Chapter 1: An Introduction to Anatomy and Physiology

Anatomy and Physiology

Introduction

Unit One of the text (Levels of Organization) consists of the first four chapters. Chapter one is titled “An Introduction to Anatomy and Physiology” and covers some basic terms and concepts regarding anatomy and physiology. Much of this information may have been covered in prior science classes, but several important ideas merit review.

Anatomy

• Anatomy is the study of structure, specifically the structures of the human body.
• This includes examining structures from the chemical level to the whole body.

Physiology

• Physiology is the study of function, or how things work.
• There is a relationship between form and function:
  • "Form follows function; function follows form."
  • Understanding this relationship allows one to infer function from structure and vice versa.

Homeostasis

• Homeostasis refers to the state of body equilibrium; the maintenance of a stable internal environment.
• The body performs thousands of functions to maintain this stable internal environment.

Stress

• Stress is anything that impacts homeostasis.
• When stress occurs, the body uses feedback mechanisms to deal with the situation:
  • Negative feedback mechanisms: Move the body back toward normal/homeostasis.
  • Positive feedback mechanisms: Move the body away from homeostasis. Example: encountering a threatening dog at night. Heart rate increases, breathing increases, sweating. These reactions are moving the metabolics away from normal.