Body Systems

1. 1
PNUR 113 – Module #2
Organization of the
Human Body

2. 2
Overview
 An understanding of the anatomy and
physiology of the body's systems is essential in
order to view the individual holistically.
 A brief description of the structure and function
of each system is presented in order to help the
learner understand how the body works as a
whole.
 The concepts of metabolism, homeostasis and
fluid balance will be introduced
 To enhance the learning of the human anatomy,
anatomical terms for the body, planes of division
and subdivisions of body cavities will be covered

3. 3
Learning Outcomes
 Upon successful completion of this module, you should be
able to:
 Describe the various levels of body organization and give
examples for each level
 Name the various systems of the body as well as give the major
structures and describe their functions
 Describe some characteristics of the living human such as
homeostasis, fluid balance and metabolism.
 Define homeostasis. Describe the role of feedback systems in homeostasis
and give examples.
 Define metabolism and distinguish between catabolism and anabolism
 Identify and use basic anatomical terms to refer to regional
names, directional terms, planes and sections, regions and
quadrants
 Identify and describe various body cavities and the organs they
contain
Answer in your own words
using complete sentences

4. Overview of Anatomy and Physiology
4

5. 5
Introductory Terms
 Anatomy: Study of the structure of the
body
 Physiology: Study of the function of the
body
 Disease: illness or abnormal state in
which part or all of the body does not
function normally
 Pathology: study of disease

6. 6
Organization
of the Human
Body
All living things are organized
from very simple levels to
more complex levels

7. 7
Organization, cont.
1. Chemical level:
 Cells are composed of chemicals such as water, proteins,
fats and carbohydrates
2. Cellular level:
 Cells contain organelles that work together to carry out a
specific function
 Ex. Epithelial cells form a barrier in skin
 Thus cells form tissues
3. Tissue Level:
 Tissues are composed of groups of cells that work together
to carry out a common function
 Ex. epithelial tissue contains a number of cell types such as
ones that fill with tough keratin and others that lay down
pigment

8. 8
Organization, cont.
4. Organs:
 Composed of groups of tissues working together to serve a
common function
 ex. epithelial tissue (epidermis) works with connective tissue
(dermis) to form the skin
 stomach composed of all four tissue types: epithelial tissue,
muscle tissue, connective tissue and nervous tissue
4. Systems:
 Organs that function together for the same general purpose
 ex. Integumentary system with skin, hair, glands, nails
 ex. Digestive system with stomach, liver, mouth, etc.
4. Body as a whole:
 Organ systems working together to maintain the body

9. 9
Organ Systems
1. Integumentary System (Dermatology)
 Skin: superficial (outer) epidermis and deep dermis
 includes hair, nails, sweat and oil glands
 Largest organ in the body
1. Skeletal System
(Orthopedics/Rheumatology)
 Includes the bones and joints
 206 bones
 Many functions
 Framework of the body
 protects internal organs
 attachment for muscles
 site of blood cell formation
 Mineral storage – calcium, phosphate

10. 10
3. Muscular System (Orthopedics)
 Includes skeletal muscles used for locomotion, posture,
chewing, speech
 Skeletal muscles also generate heat
 Tendons attach muscles to bones
 Electrically excitable and contractile
4. Endocrine System (Endocrinology)
 Glands which release hormones into blood
 Hormones travel throughout the body to target cells and
tissues with specific receptors
 Important for communication between cells and organs
 Ex. Pituitary gland produces human growth hormone that
stimulates growth of bone and other tissues
 Ex. thyroid gland produces hormones that regulate
metabolic rate
Organ Systems, cont.

11. 11
5. Nervous system (Neurology)
 Central Nervous System - Brain and spinal cord
 Nerves – peripheral nervous system
 Includes the sensory system (special senses – vision,
olfactory, taste, touch, hearing)
 Fast communication between cells and organs
 Involves the detection of a stimulus and
determination of a response
6. Circulatory system/Lymphatic system
(Cardiology, Hematology, Immunology)
 Heart, blood vessels, lymph nodes and vessels
 Transport of gases, nutrients, wastes
 Lymphatic system involved in immunity or
resistance to disease
Organ Systems, cont.

12. 12
7. Respiratory System (Respirology)
 Pair of lungs for exchange of O2 and CO2
 Passageways such as trachea, bronchi and bronchioles
to transport air to and from the lungs
 Gas exchange occurs at the tiny air sacs called alveoli
 A sheet of skeletal muscle called the diaphragm is
involved in ventilation (moving air in and out of lungs)
8. Digestive System (Gastroenterology)
 All organs involved in taking in food and converting it to
substances the body can use
 Teeth, tongue, salivary glands, stomach, intestines, liver,
pancreas, colon, etc.
Organ Systems, cont.

13. 13
9. Urinary System (Nephrology/Urology)
 Organs that filter wastes and maintains fluid balance
and pH in the body
 Kidneys, urinary bladder, ureters, urethra
10. Reproductive system (Gynocology –
Female; Urology - Male)
 Many Functions
 Production of gametes (eggs and sperm)
 Production of sex hormones (testosterone in males, estrogen
and progesterone in females)
 copulation and in females,
 development of the fetus
 Internal and external sex organs
 Female: Ovary, vagina, uterus
 Male: Testes, glands, ducts and penis
Organ Systems, cont.

14. Web Chart
for Systems
of the Body
14
Learning this
information now will
give you an advantage
down the road!

15. Discussion
 In order to prepare for the learning outcomes questions on the
midterms and final exams, practice answering the learning
outcomes from slide #3
 The subject line should include key words from the Learning
Outcome you are summarizing. In the box, type in your learning
outcome answer, in your own words, based on PowerPoint and
textbook content.
 If all learning outcomes have been covered, edit posted ones to
include missing information or make corrections.
 Post each answer separately to the Moodle Forum: Discussion
Module 2 - Organ System Learning Outcomes Short Answer for
Practice
 Return to this discussion later to see what your classmates have
posted
15
You can’t open the
quiz until you have
posted to this forum!

16. 16
Metabolism is the sum of all of the
chemical reactions occurring in the body
Metabolism = Catabolism and anabolism
Catabolism: Breaking down of complex
molecules (such as nutrients) into simpler
compounds for use by the cells resulting in
the formation of ATP (energy containing
compound)
Anabolism: manufacture of large,
complex molecules such as enzymes and
structural proteins needed for growth,
function and repair of tissues; this process
requires energy in the form of ATP
Metabolism

17. 17
Fluid Balance
 Body fluids (water) make up about 60% of adult body
weight
 Functions of fluids:
 Fluids transfer substances in and out of cells
 serve as a medium for chemical reactions
 Fluid levels must be regulated at all times
 If not, then the concentration of some dissolved substances
(solutes) can get too high or too low and cells will not
function properly
 Types of fluids:
 Intracellular fluid – found inside cells
 Extracellular fluid – found outside cells
 Includes tissue fluid (fluid between cells), blood plasma,
lymph, and others

18. 18
Homeostasis
 Homeostasis is a dynamic condition of equilibrium in the
body's internal environment produced by the interplay of
the body's regulatory processes
 We can understand what that means by first looking at the root
words that make up the word homeostasis: "homeo" = "same"
and "stasis" = “standing still" or “resting state”
 Many conditions in the body tend to stay the same — they
vary slightly, but stay close to a set point or value
 Blood pressure is regulated by the nervous system and
endocrine system to stay near a set point;
 It does vary throughout the course of a day (that is, it is dynamic,
always changing)
 These changes take place within the "body's internal
environment" - the bodily fluids

19. 19
Homeostasis - Feedback Systems
 Homeostasis is maintained by feedback systems
or feedback loops that are cycles of events in
which:
 Information about the status of a condition is constantly
monitored
 The status is then fed back and reported to a central
control region – brain usually
 Controlled Condition
 Each thing that is monitored is called a controlled
condition:
 Some controlled conditions are blood pressure, body
temperature, blood pH, blood CO2 and blood glucose
 Stimulus / Stressor
 Is any disruption that changes a controlled condition

20. 20
Negative Feedback System
 Reverses the body
condition returning to
homeostasis
 Ex. Home Heating System
 A furnace is a negative
feedback system because:
 A stimulus, the cold
temperature outdoors,
decreases the house
temperature
 The response, the
furnace turning on,
increases the house
temperature

21. 21
Negative Feedback – Body Temperature
 Ex. maintained around 37o
C
 The brain region called the hypothalamus receives
information from sensory receptors regarding body
temperature
 If the core body temperature is too high, the hypothalamus can
trigger sweat glands to cool the body
 If the core body temperature is too low, it can trigger shivering
of skeletal muscles to generate heat

22. 22
Negative Feedback – Blood Glucose
 Blood glucose levels are maintained by negative
feedback systems too, but this time the nervous system
is not involved
 Insulin is a hormone that stimulates glucose uptake into
cells so that blood glucose levels do not reach toxic
levels for the brain
 Other examples include:
 blood pressure
 blood oxygen and carbon dioxide levels
 hormone levels in the blood such as thyroid stimulating hormone
(later in the course)

23. Negative Feedback – blood glucose
23

24. 24
Positive Feedback System
 With a positive feedback system, a stimulus
enhances the original condition
 If a stimulus increases something →The
response increases it even more until the
outcome is achieved
 Ex. labour contractions
 Once they begin, positive feedback mechanisms
continue the smooth muscle contractions of the uterus
until the baby is delivered
 Ex. blood clotting
 When a vessel is punctures, this process continues
until the damaged blood vessel is sealed

25. 25
Comparing Positive and Negative
Feedback Systems
 Negative Feedback:
 Reverses the action of an
action
 Ex: Insulin secretion to
regulate blood glucose
 Positive Feedback:
 Enhances the effect of the
stimulus until the stimulus
is removed or an outside
force stops the cycle
 Ex: Childbirth –
contractions stimulate
further and stronger
contractions until child is
born

26. 26
Directions in the Body
 Anatomical position
 Refers to the body in the upright, standing
position, face front, arms at sides, palms out,
feet parallel – know this!
 In this position, directional terms apply
 They don’t apply if the person is prone (lying
on stomach) or supine (lying on back) or has
their arms raised

27. 27
Make sure you are comfortable using these
terms:
a. Superior (cephalic, cranial): above, higher than,
towards the head, upper part
Inferior (caudal): below; lower than;
away from the head
b. Anterior (ventral): before; in front of; nearer to
front
Posterior (dorsal): towards the rear;
behind; back of body
c. Medial: pertaining to the middle; nearer to
midline
Lateral: pertaining to the side; farther
from the midline
d. Proximal: nearest the point of attachment,
center of the body, or point of reference
Distal: farthest from the center, from
medial line or from trunk
e. Superficial: structure is nearer to the
surface
Directions in the Body
Anatomical
position

28. 28
Examples of usage:
a. The thoracic cavity is superior to the abdominal cavity
The pelvic cavity is Inferior to the abdominal
cavity
b. The breasts are anterior (ventral) to the vertebral
column
the buttocks are posterior (dorsal) to the pelvic
region
c. The mediastinum is medial to the lungs
the lungs are lateral to the pericardial cavity
d. The elbow is proximal relative to the wrist
the wrist is distal relative to the elbow
e. The epidermis of the skin is superficial to the
dermis
the dermis is deep to the epidermis
See if you can come up with some more examples
Directions in the Body, cont.
Anatomical
position

29. 29
Planes of Division
a. Frontal (coronal)
divides the body into
front (anterior) and back
(posterior) portions
b. Sagittal
divides the body into right
and left portions
* midsagittal
c. Transverse (cross
sectional, horizontal)
divides the body into
superior and inferior
portions

30. 30
Cross sections or transverse sections are used for
CT scans (computed tomography)
MRI (magnetic resonance imaging)
All three can be use for tissue sectioning and viewing under the
microscope
Tissue Sections
transverse

31. 31
Body Cavities
Learn these!

32. 32
Body Cavities, cont.
 dorsal cavity
1. cranial cavity: contains the brain
2. vertebral (spinal) cavity: contains the spinal cord
 ventral cavity
 Consists of:
1. Thoracic (chest) cavity – heart and lungs
2. abdominopelvic cavity – stomach, liver, bladder, etc.
 The diaphragm is a sheet of skeletal muscle that
divides the thoracic and abdominal cavities and is
important for changing pressures in these cavities
helping with ventilation of the lungs and return of blood
to the heart

33. 33
Thoracic Cavity
Subdivided into:
1. two pleural
cavities containing
the lungs
2. pericardial cavity
containing the
heart
mediastinum: central region
between the two pleural cavities
which contains heart, esophagus,
trachea, thymus gland and blood
and lymphatic vessels

34. 34
Abdominal Cavity
Learn the quadrant names and
determine which quadrant the
following are mainly found in:
stomach, liver and appendix
The abdominopelvic is
subdivided into two regions
based on location of
structures (no partition
present):
1. abdominal cavity: divided into
4 quadrants and contains
stomach, spleen, liver,
gallbladder, pancreas, small
intestine, most of the large
intestine
2. pelvic cavity: contains urinary
bladder, part of the large
intestine and reproductive
organs

35. Adjectives
for Some
Anterior
Body
Regions
35
Begin learning these
terms now!

36. Adjectives
for Some
Posterior
Body
Regions
36
Begin learning these
terms now!