1. Chapter 1 ORGANIZATION AND
GENERAL PLAN OF THE BODY
OVERVIEW AND TERMINOLOGY

2. Summary
 Definitions
 Organization of the human body
 Metabolism and Homeostasis
 Negative feedback
 Positive feedback
 Anatomical position and descriptive terms
 Body cavities
 Planes and sections

3. Definitions
 Physiology –
 Anatomy –
 ***These 2 are intimately linked –
structures designed for particular
functions.
?Pathophysiology-

4. Organization of the Human Body
 Chemicals combine to form…
 Cells, similar cells combine to form…
 Tissues, two or more tissues combine
to form an…
 Organ, two or more work together as
an…
 Organ system, all organ systems
work together to support the…
 Organism

5. Figure 1.1

6. Chemicals
 Simplest chemical is an element, 20
are found in the human body.
 Each element is composed of unique
atoms.
 Atoms combine to form molecules
and compounds:
 Inorganic –
 Organic –

7. Chemicals
 Molecules & compounds combine to
form macromolecules.
 Organic macromolecules in living
organisms:

8. Cells
 Smallest living structural and
functional units.
 Composed of organic
macromolecules.

9. Tissues
 Groups of cells with similar structure
and function.
 4 basic groups:
 Epithelial tissue –
 Connective tissue –
 Muscle tissue -
 Nerve tissue –

10. Organs
 2 or more tissues that combine to
form a structure that performs a
particular function. Examples -
 Heart
 Lungs
 ????

11. Organ System
 Group of organs that all contribute to
a certain body function.
 Cardiovascular system
 ?????
 11 organ systems: study Table 1-1,
p.7 and Figure 1-2, pp. 8-9.

12. Organ Systems
 Integumentary system: skin; protects
us from chemicals, sun, and pathogens.
 Skeletal system: bones and ligaments;
protects internal organs, provides
framework for muscles, supports the
body.
 Muscular system: muscles and tendons;
moves the skeleton, produces heat,
moves blood and food.

13. Organ Systems
 Nervous system: brain, spinal cord,
peripheral nerves, sensory organs;
collects and interprets sensory
information, regulates body functions.
 Endocrine system: glands, produce
hormones that regulate body functions.

14. Organ systems
 Circulatory system: heart, blood
vessels and blood; transports oxygen
and nutrients to tissues.
 Lymphatic system: lymph glands and
vessels; destroys pathogens and
returns tissue fluid to circulatory
system.

15. Organ Systems
 Respiratory system: lungs, trachea,
etc.; exchanges O2 and CO2 between the
body and the atmosphere.
 Digestive system: stomach, intestines,
liver, etc.; breaks down food into
nutrients and absorbs them into the
blood stream.

16. Organ Systems
 Urinary System: kidneys, urinary
bladder, urethra; removes waste
products from the blood.
 Reproductive system: ovaries, testes,
uterus, prostate gland; produces eggs or
sperm, female provides site for
developing offspring.

17. Metabolism
Sum of all chemical reactions and
processes in the body.
Anabolism –
Catabolism –
Causes changes internally and
externally. Ex. Digestion can cause
an increase in blood glucose, etc.

18. Homeostasis
 A state of relative stability within the
body despite changes in the external
and internal environment.
 Maintenance Mechanisms:
 Negative feedback – blood sugar and
temperature regulation.
 Positive feedback – fever, blood clotting
and labor.

19. Negative Feedback
Sequence:
Stimulus is “sensed” by a receptor
Receptor relays information to a control
center
Control center evaluates and creates a plan
of action
Plan sent to effector
Effector eliminates the stimulus (corrects
problems)

20. Figure 1.4

21. Negative Feedback – Temperature
Control
Figure 1.5

23. Positive Feedback
 Sequence
 Same as for negative feedback except
effector does NOT eliminate the
stimulus, it increases it.
 Requires an external “brake”.

24. Anatomical Position and
Descriptive Terms
 Anatomical position: standing
upright, facing forward, arms at the
sides palms facing forward, feet
slightly apart.
 Table 1-2 Descriptive Terms and
Table 1-3 Terms of Location and
Position
 ***Know these terms and how to use
them for the quiz and test 1.

26. Table 1.1.1

27. Table 1.1.2

28. Body Cavities and Membranes
 2 major body cavities
 Dorsal (posterior) cavity – 2 sections
 Cranial –
 Vertebral or spinal –
 The two sections are continuous and lined
by membranes called meninges.

29. Body Cavities and Membranes
 2 body cavities cont’d
 Ventral (anterior) Cavity – two major
compartments separated by the
diaphragm.
 Thoracic cavity –
 Abdominal cavity
 Pelvic cavity

31. Body Cavities and Membranes
 2 body cavities cont’d
 Ventral (anterior) Cavity Membranes
 Thoracic cavity:
 Parietal pleura lines the chest wall, visceral
pleura covers the lungs
 Visceral pericardium covers the heart and the
parietal pericardium lines the sac around the
heart.

32. Body Cavities and Membranes
 2 body cavities cont’d
 Ventral (anterior) Cavity Membranes
 Abdominal cavity:
 The peritoneum is a membrane the lines the
abdominal wall and continues into the ...
 The mesentery covers the outer surfaces of the
abdominal organs.

33. Planes and Sections
 Use: to describe internal anatomy,
orientation points, increase visibility.
 Plane: an imaginary flat surface that
separates two portions of the body,
fig 1-6.

34. Planes and Sections
 Sections: cuts in a body or organ or
plane that make the structures more
easily visible.
 Frontal or coronal section – separates
the body into front and back sections.
 Sagittal section – separates the body
into right and left portions.
 Transverse section – separates the body
into upper and lower sections.

35. Planes and Sections
o Other terms that usually refer to
organs:
o Cross section
o Longitudinal section

37. Areas of the Abdomen
 Division into 4
quadrants, fig 1-7
 RUQ
 LUQ
 RLQ
 LLQ

38. Areas of the Abdomen
 9 regions, fig 1-7
 Upper areas: left
hypochondriac,
epigastric, right
hypochondriac.
 Middle areas: left
lumbar, umbilical,
right lumbar.
 Lower areas: left
iliac, hypogastric,
right iliac.