Lecture Outline
Organization of the Body
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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
Organization of Body Parts
o
Levels of Organization
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Chemical
Cellular
Tissue
Organs
Organ Systems
Organism
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
Anatomical Terms
Anatomical position –
common reference point
for all anatomical terms
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
Anatomical Terms
Regions of the Body
o Axial portion – head, neck, and
trunk
o Appendicular portion – upper and
lower limbs
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
1.3 Body Cavities and Membranes
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Posterior (dorsal)
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Cranial cavity – contains the brain
Vertebral canal – contains the spinal
cord
Meninges – membranous layers lining
dorsal body cavity
Body Cavities and Membranes
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Anterior (ventral)
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Thoracic cavity
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Medial portion (mediastinum) – contains
the heart, thymus gland, trachea,
esophagus, and other structures
Right and left portions – contain the lungs
Body Cavities and Membranes
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Anterior (ventral)
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Abdominopelvic cavity
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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
Body Cavities and Membranes
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Parietal serous membrane – line
walls of anterior body cavities
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Thoracic cavity
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Parietal Pleura – lines thoracic cavity
Parietal pericardium – creates pericardial
cavity
Abdominopelvic cavity
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Parietal peritoneum – lines the wall of the
abdominal cavity
Body Cavities and Membranes
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Visceral serous membrane –
covers organs of the anterior body
cavity
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Thoracic cavity
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Visceral pleura – covers lung tissue
Visceral pericardium – covers heart
Abdominopelvic cavity
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Visceral peritoneum – covers many
organs in abdominopelvic cavity
Body Cavities and Membranes
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Abdominopelvic regions
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Nine regions
Four quadrants
1.4 Organ Systems
Support, Movement, and Protection
o Integumentary System
o Skeletal System
o Muscular System
Organ Systems
Integration and Coordination
o Nervous System
o Endocrine System
Organ Systems
Maintenance of the Body
o Cardiovascular System
o Respiratory System
o Digestive System
o Urinary System
Organ Systems
Reproduction and Development
o Male Reproductive System
o Female Reproductive System
1.5 Homeostasis
Homeostasis is the relative constancy of the
body’s internal environment
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External conditions may change
dramatically
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Internal conditions stay within a narrow
range
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Dynamic equilibrium – internal
conditions are not absolutely constant
o
Illness results if internal conditions
change to any great degree
Homeostasis
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Components of homeostatic
mechanisms
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Sensor – detects a change in the
internal environment
Control center – activates the effector
Effector – produces a response to the
change
Homeostasis
Negative Feedback
o Primary homeostatic mechanism
o Effector reverses the change in the
internal environment
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
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Blood clotting
Childbirth
Can be harmful
Homeostasis
Homeostasis and Body Systems
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All body systems contribute towards
maintaining homeostasis
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Disease occurs when homeostasis fails
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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