1. Lecture Outline
Organization of the Body
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2. 1.1 The Human Body
The structure of a part suits the
function of a part
o Anatomy – structure of a part
o Physiology – function of a part

3. Organization of Body Parts
o Levels of Organization
• Chemical
• Cellular
• Tissue
• Organs
• Organ Systems
• Organism

4. 1.2 Anatomical Terms
Used to describe:
o Location of body parts
o Regions of the body
o Imaginary planes by which the
body can be sectioned

5. Anatomical Terms
Anatomical position –
common reference point
for all anatomical terms

6. Anatomical Terms
Directional Terms
o Anterior (ventral)/Posterior
(dorsal)
o Superior/Inferior
o Medial/Lateral
o Proximal/Distal
o Superficial/Deep
o Central/Peripheral
o Ipsilateral/Contralateral

8. Anatomical Terms
Regions of the Body
o Axial portion – head, neck, and
trunk
o Appendicular portion – upper and
lower limbs

10. Anatomical Terms
Planes and Sections of the Body
o Sagittal (median) plane – divides
body into right and left portions
o Frontal (coronal) plane – divides
body into anterior and posterior
portions
o Transverse (horizontal) plane –
divides body into superior and
inferior portions

12. 1.3 Body Cavities and Membranes
o Posterior (dorsal)
• Cranial cavity – contains the brain
• Vertebral canal – contains the spinal
cord
• Meninges – membranous layers lining
dorsal body cavity

13. Body Cavities and Membranes
o Anterior (ventral)
• Thoracic cavity
 Medial portion (mediastinum) – contains
the heart, thymus gland, trachea,
esophagus, and other structures
 Right and left portions – contain the lungs

14. Body Cavities and Membranes
o Anterior (ventral)
• Abdominopelvic cavity
 Superior portion (abdominal cavity) –
contains the stomach, liver, spleen,
gallbladder, and most of the small and
large intestines
 Inferior portion (pelvic cavity) – contains
the rectum, urinary bladder, internal
reproductive organs, and the rest of the
large intestine

16. Body Cavities and Membranes
o Parietal serous membrane – line
walls of anterior body cavities
• Thoracic cavity
 Parietal Pleura – lines thoracic cavity
 Parietal pericardium – creates pericardial
cavity
• Abdominopelvic cavity
 Parietal peritoneum – lines the wall of the
abdominal cavity

17. Body Cavities and Membranes
o Visceral serous membrane –
covers organs of the anterior body
cavity
• Thoracic cavity
 Visceral pleura – covers lung tissue
 Visceral pericardium – covers heart
• Abdominopelvic cavity
 Visceral peritoneum – covers many
organs in abdominopelvic cavity

19. Body Cavities and Membranes
o Abdominopelvic regions
• Nine regions
• Four quadrants

21. 1.4 Organ Systems
Support, Movement, and Protection
o Integumentary System
o Skeletal System
o Muscular System

22. Organ Systems
Integration and Coordination
o Nervous System
o Endocrine System

23. Organ Systems
Maintenance of the Body
o Cardiovascular System
o Respiratory System
o Digestive System
o Urinary System

24. Organ Systems
Reproduction and Development
o Male Reproductive System
o Female Reproductive System

25. 1.5 Homeostasis
Homeostasis is the relative constancy of the
body s internal environment
o External conditions may change
dramatically
o Internal conditions stay within a narrow
range
o Dynamic equilibrium – internal
conditions are not absolutely constant
o Illness results if internal conditions
change to any great degree

26. Homeostasis
o Components of homeostatic
mechanisms
• Sensor – detects a change in the
internal environment
• Control center – activates the effector
• Effector – produces a response to the
change

27. Homeostasis
Negative Feedback
o Primary homeostatic mechanism
o Effector reverses the change in the
internal environment

31. Homeostasis
Positive Feedback
o Effector continues to stimulate the
sensor so that a greater change in
the internal environment occurs
o Helps in completing a process that
has a cutoff point
• Blood clotting
• Childbirth
o Can be harmful

33. Homeostasis
Homeostasis and Body Systems
o All body systems contribute towards
maintaining homeostasis
o Disease occurs when homeostasis fails
• Local disease – restricted to a specific part
of the body
• Systemic disease – affects several organ
systems or the entire body
• Acute diseases – occur suddenly and last a
short time
• Chronic diseases – develop slowly and are
long term