CHAPTER 1 AN INTRODUCTION TO ANATOMY & PHYSIOLOGY Pictures from Essentials of Anatomy & Physiology, Third Edition

I. Introduction (basic functions of all living things) A. Responsiveness – immediate (irritability), long term changes (adaptability). Important for the basis of homeostasis (maintaining balance) B. Growth (organism gets larger through increase in cells) C. Reproduction

D. Movement – internal (transporting food or blood) external (locomotion) E. Metabolism – all the chem rxs in the body Catabolic rxs – break down Anabolic rxs – build up

II. The Sciences of Anatomy and Physiology Anatomy – internal & external structure Physiology – function of the structure If you change the structure it no longer performs its original function

A. Microscopic Anatomy (structures not seen w/o magnification) Cytology – analyzes the internal structures of cells – cell biology Histology – examines tissues

B. Gross Anatomy (macroscopic-visible with unaided eye) Surface anatomy – general form & superficial markings Regional anatomy – superficial & internal features of a specific region Systemic anatomy – structure of major organ systems

C. Physiology Cell Physiology – functions of cells & chem processes Special Physiology – specific organs (kidney, heart) System Physiology – all aspects of an organ system (respiratory, excretory) Pathological Physiology – effects of diseases

III. Levels of Organization Changes at the lowest level affect the whole organism!! A. Chemical or Molecular Level – atoms & molecules, shape is important B. Cellular Level – smallest living unit, organelles have specific functions C. Tissue Level – similar cells performing a specific function

D. Organ Level – 2 or more tissues together to perform a specific function E. Organ System Level – all the structures that make the organ function – heart, blood vessels, blood F. Organism Level – all organs working together Damage to 1 level can affect another level – blood loss

IV. An Introduction to Organ Systems - know the major functions of each. A. Integumentary B. Skeletal C. Muscular D. Nervous E. Endocrine F. Cardiovascular G. Lymphatic H. Respiratory I. Digestive J. Urinary K. Male Reproductive L. Female Reproductive

Protects, maintains body temp

Support, protects tissues, stores mineral, forms blood

Locomotion, provides support, produces heat

Directs immediate response to stimuli, coordinates activities of other organ systems

Directs long term changes in activities of other organ systems

Transports cells & dissolved materials (nutrients, wastes, gases)

Defends against infection & disease, returns tissue fluid to bloodstream

Delivers air to sites where gas exchange occurs between air & blood

Processes food & absorbs nutrients

Eliminates excess water, salt, waste products

Produce sperm & hormones

Produce eggs & hormones

V. Homeostasis and System Integration We are never physiologically in a state of “unchanging sameness” – unless you’re dead! A. Homeostatic Regulation Responses to stimulus to maintain our stable internal environment (or adjustments in physiological systems to preserve homeostasis) Receptor (sensitive to stimulus), Control Center (receives & processes info), Effector (responds to stimulus)

Operates like a thermostat – heater turns on if room becomes cold (winter) and the AC turns on if the room becomes to hot (summer)

Negative Feedback A variation outside normal limits triggers an automatic response that corrects the situation Effector that is activated by the control center opposes or eliminates the stimulus Most mechanisms in body operate this way Example: thermoregulation (body temp)

Negative feedback

Positive Feedback Loop Initial stimulus produces a response that reinforces the stimulus Important in accelerating processes that must proceed to completion quickly Example: blood clotting (releases chemicals that accelerate the process until bleeding stops)

Positive feedback

Homeostasis & Disease When homeostatic regulation fails, organ systems malfunction and the individual experiences illness or disease

VI. The Language of Anatomy A. Surface Anatomy Anatomical Landmarks - refer to Fig Know only those terms in bold type.  Supine – face up  Prone – face down

Anatomical landmarks

Anatomical Regions – refer to Table 1-1. Anatomical Directions - refer to Fig. 1-7 and the directional references diagram at end of notes. Best to study in pairs. Know directions and Table 1-2.

Directional references

B. Sectional Anatomy Planes and Sections - refer to planes of section diagram at end of notes. Know.  Transverse – superior & inferior pieces  Frontal – anterior & posterior pieces  Sagittal – right & left pieces

Planes of sections

Body Cavities (2 functions)  Protect organs (brain, spine)  Permit significant changes in size & shape of visceral organs (heart, lungs, stomach) Lined with serosal membranes that secrete serosal fluid

Dorsal Body Cavities Cranial - encloses brain Spinal – surrounds spinal cord

Ventral Body Cavities Most organs are surrounded by moist internal spaces that allow for expansion but prevent friction