The Human Body: An Orientation

Transcription

1 1 The Human Body: An Orientation Yong Jeong, MD, PhD Department of Bio and Brain Engineering 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 1

2 Anatomy Levels of Study Gross anatomy Large structures Easily observable Figure 14.1 Anatomy Levels of Study Microscopic Anatomy Very small structures Can only be viewed with a microscope Figure 14.4c d 2

3 Levels of Structural Organization Smooth muscle cell Cellular level Cells are made up of molecules Molecules Atoms Chemical level Atoms combine to form molecules Tissue level Tissues consist of similar types of cells Smooth muscle tissue Epithelial tissue Smooth muscle tissue Connective tissue Organ level Organs are made up of different types of tissues Blood vessel (organ) Cardiovascular system Organ system level Organ systems consist of different organs that work together closely Organismal level Human organisms are made up of many organ systems Figure

4 Organ System Overview Integumentary Forms the external body covering Protects deeper tissue from injury Helps regulate body temperature Location of cutaneous nerve receptors Figure 1.2a Organ System Overview Skeletal Protects and supports body organs Provides muscle attachment for movement Site of blood cell formation Stores minerals Figure 1.2b 4

5 Organ System Overview Muscular Produces movement Maintains posture Produces heat Figure 1.2c Organ System Overview Nervous Fast-acting control system Responds to internal and external change Activates muscles and glands Figure 1.2d 5

6 Organ System Overview Endocrine Secretes regulatory hormones Growth Reproduction Metabolism Figure 1.2e Organ System Overview Cardiovascular Transports materials in body via blood pumped by heart Oxygen Carbon dioxide Nutrients Wastes Figure 1.2f 6

7 Organ System Overview Lymphatic Returns fluids to blood vessels Cleanses the blood Involved in immunity Figure 1.2g Organ System Overview Respiratory Keeps blood supplied with oxygen Removes carbon dioxide Figure 1.2h 7

8 Organ System Overview Digestive Breaks down food Allows for nutrient absorption into blood Eliminates indigestible material Figure 1.2i Organ System Overview Urinary Eliminates nitrogenous wastes Maintains acid-base balance Regulates water and electrolytes Figure 1.2j 8

9 Organ System Overview Reproductive Produces offspring Figure 1.2k l Interrelationships Among Body Systems 9

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 10

11 Necessary Life Functions Metabolism chemical reactions within the body Produces energy Makes body structures Excretion Eliminates waste from metabolic reactions Reproduction Produces future generation Growth Increases cell size and number of cells Survival Needs Nutrients Chemicals for energy and cell building Includes carbohydrates, proteins, lipids, vitamins, and minerals Oxygen Required for chemical reactions 11

12 Survival Needs Water 60 80% of body weight Provides for metabolic reaction Stable body temperature Atmospheric pressure Must be appropriate 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 12

13 Input: Information sent along afferent pathway to Receptor (sensor) Control center Output: Information sent along efferent pathway to activate Effector Change detected by receptor Stimulus: Produces change in variable Variable (in homeostasis) Response of effector feeds back to influence magnitude of stimulus and returns variable to homeostasis Figure 1.4 cf: Steady state Biomedical Engineering Mark Saltzman

14 cf: Equilibrium Maintaining Homeostasis The body communicates through neural and hormonal control systems Receptor Responds to changes in the environment (stimuli) Sends information to control center 14

15 Maintaining Homeostasis Control center Determines set point Analyzes information Determines appropriate response Effector Provides a means for response to the stimulus Feedback Mechanisms Negative feedback Includes most homeostatic control mechanisms Shuts off the original stimulus, or reduces its intensity Works like a household thermostat 15

16 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? The Language of Anatomy Special terminology is used to prevent misunderstanding Exact terms are used for Position Direction Regions Structures 16

17 Regional Terms Anterior body landmarks Figure 1.5a Regional Terms Posterior body landmarks Figure 1.5b 17

18 Directional Terms Table 1.1 (1 of 3) Directional Terms Table 1.1 (2 of 3) 18

19 Directional Terms Table 1.1 (3 of 3) Body Planes and Sections Figure

20 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 Rostral (beak) vs. caudal (tail): embryology base Superior vs. inferior 20

21 Body Cavities Dorsal 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 21

22 Body Cavities Figure 1.7 Abdominopelvic Quadrants Figure 1.8a 22

23 Abdominopelvic Regions Figure 1.8b Abdominopelvic Major Organs Figure 1.8c 23