1. The Human Body: An Orientation
Chapter 1
The Human Body: An Orientation

2. The Human Body—An Orientation
Anatomy
Study of the structure and shape of the body and its parts
Physiology
Study of how the body and its parts work or function

3. Anatomy—Levels of Study
Gross anatomy
Large structures
Easily observable
Figure 14.1

4. Anatomy—Levels of Study
Microscopic Anatomy
Very small structures
Can only be viewed with a microscope
Figure 14.4c–d

5. Sub-divisions of Human Physiology
Cellular Physiology- interactions b/w cell parts and organelle function.
Developmental Physiology- changes throughout the development of an organism.
Pathological Physiology- function changes that occur to organs over time.

6. Characteristics of Living things
Metabolism
Responsiveness
Growth
Movement
Differentiation
Reproduction

7. Levels of Structural Organization
Smooth muscle cell
Molecules
Atoms
Smooth muscle tissue
Epithelial tissue
Connective tissue
Blood vessel (organ)
Cardio- vascular system
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 Human organisms are made up of many organ systems
Chemical level Atoms combine to form molecules
Levels of Structural Organization
Figure 1.1

8. How are cells bound together?
Similar cells are bound by the matrix! This could be liquid, solid or semi-solid in nature.
Ex: Blood-liquid, bone cells-solid
Similar cells bound together by the matrix are considered TISSUES.
The study of tissues is called Histology.

9. 4 Principal tissues & functions!
1- Epithelial- covers body and organ surfaces, lines body cavities. Involved in protection, absorption, excretion, and secretion.
2- Connective- binds, supports and protects body parts.
3- Muscle- Permits locomotion by moving the skeleton.
4- Nervous- initiates and transfers electrical impulses that coordinate the body
4 Principal tissues & functions!

10. Necessary Life Functions
Maintain boundaries
Movement
Locomotion
Movement of substances
Responsiveness
Ability to sense changes and react
Digestion
Break-down and absorption of nutrients

11. Necessary Life Functions
Metabolism—chemical reactions within the body
Produces energy
Makes body structures
Excretion
Eliminates waste from metabolic reactions

12. Necessary Life Functions
Reproduction
Produces future generation
Growth
Increases cell size and number of cells

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

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

15. Interrelationships Among Body Systems
Figure 1.3

16. Homeostasis Homeostasis—maintenance of a stable internal environment
A dynamic state of equilibrium
Homeostasis is necessary for normal body functioning and to sustain life
Homeostatic imbalance
A disturbance in homeostasis resulting in disease

17. Variable (in homeostasis)
Input: Information sent along afferent pathway to
Control center
Output: Information sent along efferent pathway to activate
Receptor (sensor)
Effector
Change detected by receptor
Response of effector feeds back to influence magnitude of stimulus and returns variable to homeostasis
Stimulus: Produces change in variable
Imbalance
Variable (in homeostasis)
Imbalance
Figure 1.4

18. Variable (in homeostasis)
Figure 1.4, step 1a

19. Variable (in homeostasis)
Stimulus: Produces change in variable
Imbalance
Variable (in homeostasis)
Imbalance
Figure 1.4, step 1b

20. Variable (in homeostasis)
Receptor (sensor)
Change detected by receptor
Stimulus: Produces change in variable
Imbalance
Variable (in homeostasis)
Imbalance
Figure 1.4, step 2

21. Variable (in homeostasis)
Input: Information sent along afferent pathway to
Control center
Receptor (sensor)
Change detected by receptor
Stimulus: Produces change in variable
Imbalance
Variable (in homeostasis)
Imbalance
Figure 1.4, step 3

22. Variable (in homeostasis)
Input: Information sent along afferent pathway to
Control center
Output: Information sent along efferent pathway to activate
Receptor (sensor)
Effector
Change detected by receptor
Stimulus: Produces change in variable
Imbalance
Variable (in homeostasis)
Imbalance
Figure 1.4, step 4

23. Variable (in homeostasis)
Input: Information sent along afferent pathway to
Control center
Output: Information sent along efferent pathway to activate
Receptor (sensor)
Effector
Change detected by receptor
Response of effector feeds back to influence magnitude of stimulus and returns variable to homeostasis
Stimulus: Produces change in variable
Imbalance
Variable (in homeostasis)
Imbalance
Figure 1.4, step 5

24. Maintaining Homeostasis
The body communicates through neural and hormonal control systems
Receptor
Responds to changes in the environment (stimuli)
Sends information to control center

25. Maintaining Homeostasis
Control center
Determines set point
Analyzes information
Determines appropriate response
Effector
Provides a means for response to the stimulus

26. Feedback Mechanisms Negative feedback
Includes most homeostatic control mechanisms
Shuts off the original stimulus, or reduces its intensity
Works like a household thermostat

27. Feedback Mechanisms Positive feedback
Increases the original stimulus to push the variable farther
In the body this only occurs in blood clotting and during the birth of a baby

28. The Language of Anatomy
Special terminology is used to prevent misunderstanding
Exact terms are used for
Position
Direction
Regions
Structures

29. Regional Terms
Anterior body landmarks
Figure 1.5a

30. Regional Terms
Posterior body landmarks
Figure 1.5b

31. Directional Terms
Table 1.1 (1 of 3)

32. Directional Terms
Table 1.1 (2 of 3)

33. Directional Terms Website Fill in the blanks! Fill in the blanks 2
Table 1.1 (3 of 3)

34. Body Planes and Sections
A sagittal section divides the body (or organ) into left and right parts
A median, or midsagittal, section divides the body (or organ) into equal left and right parts
A frontal section divides the body (or organ) into anterior and posterior parts
A transverse, or cross, section divides the body (or organ) into superior and inferior parts

35. Body Planes and Sections interactive!! Interactive 2
Figure 1.6

36. These are computed tomography scans and magnetic resonance images.
CT Scans & MRI’s
These are computed tomography scans and magnetic resonance images.
These scans are much more helpful because they can give both sagittal and transverse images as compared to X-rays which can only be taken on a vertical plane.

37. Body Cavities Dorsal body cavity Ventral body cavity
Cranial cavity houses the brain
Spinal cavity houses the spinal cord
Ventral body cavity
Thoracic cavity houses heart, lungs and others
Abdominopelvic cavity houses digestive system and most urinary system organs

38. Body Cavities
Figure 1.7

39. Abdominopelvic Quadrants
Figure 1.8a

40. Abdominopelvic Regions Web!
Figure 1.8b

41. Abdominopelvic Major Organs Game Website
Figure 1.8c