1. Human Anatomy and Physiology
Chapter 1 The Human Body: An Orientation

3. Anatomy
Structure
Parts
Shape

4. Physiology
Functions

5. “Structure Determines Function”
Definitions
Anatomy (ana = up; tomy = cutting)
Study of the human body (morphology)
Dissection (dis = apart; section = act of cutting)
Physiology (physio = nature; logy = study of)
Study of body function
“Structure Determines Function”

6. Gross Anatomy
Microscopic Anatomy

7. The Hierarchy of Structural Organization
Organelle
Molecule
Atoms
Chemical level
Atoms combine to
form molecules.
Cellular level
Cells are made up
of molecules.
Tissue level
Tissues consist of
similar types of cells
Organ level
Organs are made up of
different types of tissues.
Organ system level
Organ systems consist of
different organs that work
together closely.
Organismal level
The human organism
is made up of many
organ systems.
Cardiovascular
system
Smooth muscle cell
Smooth muscle tissue
Connective tissue
Blood vessel
(organ)
Heart
Blood
vessels
Epithelial
tissue 1 2 3 4 5 6
Figure 1.1

8. Chemical, Cellular, and Tissue Levels
Chemical Level: atoms form molecules  macromolecules
Four classes of macromolecules
Cellular Level: cells and their functional subunits
Smallest living unit of life
Structure of each cell type is related to its function
Tissue level: group of cells performing a common function
Four major types

9. Organ, Organ System, and Organism Levels
Organ level: discrete structure made up of more than one tissue
Organ system: organs working together to perform a common function
Organism level: the result of all simpler levels working together to sustain life
Homeostasis (homeo, unchanging + stasis, standing)
Disease: failure of maintaining homeostasis

10. Levels of Structural Organization
Chemical level 
Cellular level
Tissue level 
Organ level 
Organ System 
Organism level 

11. 11 Major Systems of the Body
Integumentary
Skeletal
Muscular
Nervous
Endocrine
Cardiovascular
Lymphatic
Respiratory
Digestive
Urinary
Reproductive

12. Integumentary System Forms the external body covering
Protects deeper tissue from injury
Synthesizes vitamin D
Location of cutaneous nerve receptors

13. Skeletal System Protects and supports body organs
Provides muscle attachment for movement
Site of blood cell formation
Stores minerals

14. Muscular System
Allows locomotion
Maintains posture
Produces heat

15. Nervous System Fast-acting control system
Responds to internal and external change
Activates muscles and glands

16. Endocrine System Secretes regulatory hormones Growth Reproduction
Metabolism

17. Cardiovascular System
Transports materials in body via blood pumped by heart
Oxygen
Carbon dioxide
Nutrients
Wastes

18. Lymphatic System Returns fluids to blood vessels Disposes of debris
Involved in immunity

19. Respiratory System Keeps blood supplied with oxygen
Removes carbon dioxide

20. Digestive System Breaks down food
Allows for nutrient absorption into blood
Eliminates indigestible material

21. Urinary System Eliminates nitrogenous wastes
Maintains acid – base balance
Regulation of materials
Water
Electrolytes

22. Reproductive System
Production of offspring
Development

23. Necessary Life Functions
Maintain Boundaries
Movement
Locomotion
Movement of substances
Responsiveness
Ability to sense changes and react
Digestion
Break-down and delivery of nutrients

24. Necessary Life Functions
Metabolism – chemical reactions within the body
Production of energy
Making body structures
Excretion
Elimination of waste from metabolic reactions

25. Necessary Life Functions
Reproduction
Production of future generation
Growth
Increasing of cell size and number

26. Survival Needs Nutrients Oxygen Chemicals for energy and cell building
Includes carbohydrates, proteins, lipids, vitamins, and minerals
Oxygen
Required for chemical reactions

27. Survival Needs Water Stable body temperature
60–80% of body weight
Provides for metabolic reaction
Stable body temperature
Atmospheric pressure must be appropriate

28. Homeostasis
Maintenance of a stable internal environment = a dynamic state of equilibrium

29. Set Point Range
Cold
Comfy
Hot
Comfy

30. Homeostasis
Homeostasis must be maintained for normal body functioning and to sustain life
Homeostatic imbalance – a disturbance in homeostasis resulting in disease

31. Feedback Control Loop
Hello
It’s Hot

32. Feedback Control Loop: Basic Components
Sensor mechanism
Integrating or control center
Effector mechanism

33. Direction of Signals
afferent
efferent

34. Feedback Control Loop: Basic Components
Sensor mechanism (neural or hormonal)
Afferent signal
Integrating or control center
Efferent signal
Effector mechanism

35. Negative Feedback Loop
Cold
Heat

36. Positive Feedback Control Loop
Cold
Cold