1. Human Body Orientation
Chapter 1
Human Body
Orientation

2. Anatomy Study of structure Types
Gross Anatomy: the study of large body structures visible to the naked eye such as the heart or lungs
Microscopic Anatomy: the study of structures too small to be seen without a microscope such as tissues and cells
Developmental Anatomy: the study of structural changes that occur in the body throughout the lifespan

3. Physiology The study of the function of the body Types
Renal Physiology: kidney function and urine production
Neurophysiology: nervous system
Cardiovascular Physiology: heart and blood vessels

4. Structure determines Function
How a cell looks determines what the cell does. (ex. Long dendrites on a nerve cell allows it to send signals quickly)
How an organ looks determines how well it functions.

5. Levels of Structural Organization
1. chemical level (atoms & molecules)
2. cellular level (cells & organelles)
3. tissue level (groups of similar cells that have a common function)
4. organ level (discrete structures composed of at least two tissue types)
5. organ system (organs work together to accomplish a common purpose)
6. organismal level (the sum total of all structural levels)

6. Necessary Life Functions
1. maintaining boundaries: internal boundaries remain distinct from external environment
2. movement: activities of the muscular system, etc.
3. responsiveness: the ability to sense changes (stimuli) and respond to them
4. digestion: breaking down food to simple molecules
5. metabolism: chemical reactions in the body
6. excretion: removing wastes
7. reproduction: cellular or organismal
8. growth: increase in the size of cells, body parts, or the organism itself

7. Survival Needs
1. nutrients: contain the chemical substances used for energy and cell building
2. oxygen: allows cellular respiration to occur
3. water: accounts for 60-80% of body weight, needed for chemical reactions
4. normal body temperature: maintains metabolic reactions
5. atmospheric pressure: needed for proper breathing and gas exchange in the lungs

8. Homeostasis The ability to maintain a stable internal environment
Every organ system plays a role in maintaining the constancy of the internal environment

9. Negative Feedback
The output shuts off the original stimulus or reduces its intensity (prevents sudden severe changes in the body)
These mechanisms cause the variable to change in a direction opposite to that of the initial change
Ex. Body temperature and blood volume

10. Positive Feedback
The response enhances the original stimulus so that the activity is accelerated
The change that occurs is in the same direction as the initial disturbance
Ex. Oxytocin: intensifies labor contractions

11. Response to Environment
Nervous system – electrochemical
Afferent pathway – (arriving) receptor stimuli to control center
Efferent pathway – (exiting) control center
Ex. hot stove and hand
Endocrine system – hormones
Ex. insulin and glucose

12. Orientation and Direction
Cranial
Caudal
Ventral
Dorsal
Superior
Inferior
Medial
Lateral
Proximal
Distal

13. Body Planes and Sections
Sagittal: divides body into right and left
Median: sagittal along the midline
Frontal (coronal): divides body into anterior and posterior
Transverse: horizontal; divides body into superior and inferior parts

14. Body Cavities Dorsal Ventral Cranial & vertebral Thoracic Abdominal
Pleural cavities – houses lungs
Mediastinum – houses heart, trachea, esophagus
Abdominal
-- Pelvic

15. Membranes of Body Cavities
Serous membranes
Covering on organs
Parietal serosa: lines the cavity walls
Visceral serosa: covers the organs
Serous fluid: lubricating fluid
Peritonitis- inflammation of the membrane lining of the abdominal cavity

16. Abdominopelvic Quadrants

17. Other Body Cavities 1. oral and digestive 2. nasal 3. orbital
4. middle ear
5. synovial

18. 11 Systems Cardiovascular Skeletal Integumentary Lymphatic Urinary
Muscular
Digestive
Respiratory
Reproductive
Nervous
Endocrine