1. Chapter One: The Human Body M.C. Shamier, MD Shenzhou University

2. Subjects  Anatomy  Anatomy defined  The language of anatomy  Physiology  Physiology defined  Levels of organization  Homeostasis

3. Anatomy  Greek: ἀνατέμνειν “to cut open”  tonsillec-tomy: cutting away the tonsils of the throat.  The study of the structure of living things  Michiel van Mierevelt, 1617

4. Subdivisions  Gross or macroscopic anatomy  Microscopic anatomy  Histology  Cytology  Developmental anatomy and embryology  Radiographic anatomy  Pathological anatomy

5. Histology and cytology

6. Radiographic and pathological anatomy

7. The language of anatomy  Anatomical position  Directional terms  Regional names  Body planes  Abdominopelvic regions  Body cavities Arbitrary Physiologic

8. The language of anatomy

9. Anatomical position

10. Directional terms

15. Regional names

16. Body planes

17. Abdominopelvic regions

18. Body cavities “Body cavities are spaces within the body that are closed to the outside and contain the internal organs.”

19. Body cavities

20. Example: cranial and spinal cavity  Together one continuous space, home to the central nervous system (CNS)  Confined by bone: skull and vertebral column  Filled with cerebrospinal fluid

21. Are there any questions?

22. Next: Physiology

23. Physiology  Greek:  Φύσις : “nature  - λογία : “the study of”  The science of the functioning of living things.  Inseperately connected to anatomy:  function reflects shape

24. Levels of structural organization  Question:  What is the smallest unit that the body is essentially composed of?

25. Levels of structural organization

26. Question  Could you think of a seventh level?

27. The seventh level: environmental context Hendrick Avercamp New York City

28. And the environment also contains: Yellow fever

29. Organism and environment  The organism is subject to:  Climate  Microbes  Social interaction  Air pressure  And dependent on the environment for:  Oxygen  Nutrients  Water

30. Boundaries  Question:  What seperates the organism from its environment?

31. ‘Milieu intérieur’ and ‘milieu extérieur’  “The fixity of the milieu supposes a perfection of the organism such that the external variations are at each instant compensated for and equilibrated. All of the vital mechanisms, however varied they may be, have always one goal, to maintain the uniformity of the conditions of life in the internal environment. The stability of the internal environment is the condition for the free and independent life.”  Claude Bernard, French Physiologist, 1854:

32. Example: Temperature  Question  What is the baseline temperature of the human body?  Question  What happens when the environmental temperature drops?

33. Example: Temperature

34. This is called: Homeostasis  Homeostasis:  The ability of the body to maintain a relatively constant internal environment, regardless of environmental changes.

35. How does it work? The mechanism of negative feedback: failure leads to imbalance which means disease.

36. Concluded  There are several levels of structural organization within an organism: from the atom to the organism (living in an environment).  All vital systems work together to maintain a stable internal environment, compensating for external variations. The mechanism is negative feedback.  This is called homeostasis.

37. End of Chapter One