Chapter 1 Lecture: The Human Body – An Orientation
I. Overview of Anatomy
A. Anatomy: Structure and location of parts of the body (The machinery)
B. Anatomy can be broken down into 4 different areas of study
1. Gross/Macroscopic: study of large body structures
a. Regional – all structures in 1 part of the body
ex. Arm, leg, abdomen
b. Systemic – study of structures by systems
ex. Cardiovascular system = heart and vessels
c. Surface – study of internal structures with respect to (wrt)
skin surface
2. Microscopic
a. Cytology – study of cells
b. Histology – study of tissues
3. Developmental
a. follows changes in anatomical structure throughout life
b. Embryology: looks at developmental changes before birth
4. Specialized Branches: Research and Medical Diagnosis
a. Pathological: structural changes due to disease
b. Radiographic: studies in internal structures visualized by
x-rays, CT scans, MRI
c. Molecular: study of molecules at the subcellular level
II. Overview of Physiology
A. Physiology: Function of the body parts (how the machinery works)
1. Dynamic and animated
2. Requires understanding of
a. cells
b. molecules  chemical reactions
c. chemistry
d. physics
B. Principle of Complementarity:
1. Function Reflects Structure: what structure can do depends on
its form
Ex. Blood flows in one direction (physiological function)
directly related to one-way heart valves (structural anatomy)
III. Structural Organization:
A. Atoms: combine to form molecules
B. Molecules: makes up chemicals, proteins, ATP, for example
C. Organelles: made up of proteins, chemicals, and molecules
D. Cells: made up of organelles and other abiotic molecules like water
E. Tissues: Similar types of cells with a common function
Ex. Epithelial tissue, smooth muscle tissue, connective tissue,
glandular tissues, vascular tissues
F. Organs: composed of two or more tissue types performing a specific
Ex. Stomach:
G. Organ systems: several organs working together to accomplish a
common purpose
Ex. Digestive: esophagus, stomach, small and large intestine, liver,
H. Organism level
IV. Body Systems
A. Integumentary system: body coverings– skin, hair, nails, sweat glands
1. protection
2. regulates body temp
3. environmental sensors
4. makes vitamin D
B. Skeletal system: Bones, cartilage, ligament and joints
1. provides muscles framework
2. protects organs
3. form blood cells
4. stores minerals like calcium
C. Muscular system: muscles and tendons
1. contraction (shortening) of muscles causing motion
2. maintains posture
D. Nervous system: brain, spinal cord, nerves, sensory receptors.
1. detects changes internally and externally
2. processes incoming information and directs response
3. responds to env’t by activating glands/muscles
E. Endocrine system: glands, hormones
1. regulatory system
Ex. Metabolism, growth, reproduction
2. Synchronizes all body systems
F. Cardiovascular system: heart and blood vessels
1. transports gases, chemicals, white blood cells that fight infection
2. transports nutrients, eliminates waste
G. Lymphatic system: lymph nodes, vessels, red bone marrow, thymus,
1. involved in immune response
a. Disposes of pathogens and debris
b. houses lymphocytes (wbc)
2. return fluids in tissues to the blood vessels
H. Respiratory system: nose, pharynx, larynx, trachea, lungs, diaphragm
1. supplies body with oxygen, removing carbon dioxide
I. Digestive system: mouth, esophagus, stomach, intestines, liver, and
other glands
1. break down food and deliver nutrients to body tissues
2. eliminates indigestible food
J. Urinary systems: kidneys, ureters, bladder, urethra
1. removing wastes from the blood stream and flush from body.
2. maintains water, electrolytes, and pH balance of body
K. Reproductive system: production of offspring
V. Characteristics of life
A. Functional characteristics: Organ systems do not work in isolation.
They work cooperatively and have inter-relationships.
1. Maintaining Boundaries: every organism makes internal env’t
distinct from external one
a. cellular level: p. membrane
b. organismal level: skin/integument
2. Movement: locomotion, propulsion through internal organs
a. contractility (cellular level): shortening of muscle cells
b. ex. of inter-relationship: skeletal, muscular systm
3. Responsiveness/Irritability: sense change in env’t (stimuli) and
a. ex. of inter-relationship: nerve cells of nervous systm
(highly irritable), skeletal, muscular sytm
4. Digestion: food broken down into simpler forms:
macromolecules, and absorbed by cells
a. ex. of inter-relationship: digestive and circulatory systems
5. Metabolism: sum of all chemical rxns in body
a. catabolism: breaking down of substances (via dehydration
synthesis, bond breaking, energy release)
b. anabolism: building of substances (via hydrolysis, bond
forming, energy stored)
c. cellular respiration: converting food energy into ATP, using
d. ex. of inter-relationship: hormones of endocrine system,
circulatory systm
6. Excretion: removal of waste produced during digestion and
a. ex. of inter-relationship: digestive and respiratory systms
7. Reproduction: making new individual at 2 levels
a. cellular level: by mitosis followed by cytokinesis, for
growth and repair. Produces more cells.
b. organismal level: union of sperm and egg
8. Growth: increasing in body part or overall size of organism
B. Survival Needs
1. Nutrients (via diet): chemical substances for energy and cell
2. Oxygen: to release energy from foods via cellular respiration.
3. Water: Provides env’t for chemical reactions and excretion
4. Proper body temperature: to maintain chemical reactions.
a.Too low – chemical rxns slow
b. Too high – changes shape of proteins (denaturization),
which causes them to be non-functional
c. heat generated by muscles
5. Atmospheric pressure: force air exerts on the body.
a. influence gas exchange, breathing
VI. Homeostasis (use Venn diagram in intNB – student correct or add to own diagram)
A. Maintenance of a relatively stable internal environment (w/in ranges) in
an ever-changing external env’t
1. dynamic state of equilibrium
B. Accomplished by communication within body via 2 systems
1. nervous system: detecting changes through nerve/electrical
2. endocrine system: glands release hormones that communicate
between organ systems and react to change
C. Homeostasis controlled by
1. receptors: detect change (stimuli) and send information (input) to
the control center
2. control center (brain): determines set-point to be maintained.
Determines course of action.
3. effector: the organ or structure that responds to the stimulus and
either reverses it or enhances it.
D. Two forms of Homeostatic Control
1. Negative Feedback: the effect of the response is to reverse the
original stimulus.
a. Examples: body temperature:
-. if too high – blood vessels dilate, body sweats to
release heat
- if too low – blood vessels constrict into the body,
goose bumps conserve heat.
2. Positive Feedback: effect of the response is to continue the
original stimulus
a. Examples
- Reward sytm in school
- Labor contractions due to oxytocin
- Blood clotting: platelets release chemicals that
attract more platelets
E. Homeostatic imbalance = disease
1. Aging decreases ability to maintain homeostasis
VII. Language of Anatomy
A. Anatomical position:
1. body erect
2. palms forward, thumbs away
3. feet slightly apart
4. R is always the specimen’s right side.
B. Body Regions
1. Axial: main axis of the body
– head, neck, trunk of body
2. Appendicular – limbs & attachments
C. Orientation & Direction
1. Superior: upper, or above something
2. Inferior: lower, or below something
3. Anterior or Ventral: front, in front of, or belly
4. Posterior or Dorsal: after, behind, toward the rear, back
5. Medial: toward the mid-line, middle, away from the side
6. Lateral: toward the side of the body - away from the mid-line
7. Proximal: toward or near the trunk of the body, near the point
of attachment to the body
8. Distal: away from, farther from the origin or attachment to the
9. Cranial: towards head of the body
10. Caudal: towards feet
11. Superficial: external, near the body surface
12. Deep: internal, away from the body surface
D. Body Landmarks
1. Anterior
a. Abdominal
b. Antebrachial: forearm
c. Antecubital: anterior elbow surface
d. Axillary: armpit
e. Brachial: arm
f. Carpal: wrist
g. Cervical: neck region
h. Coxal: hip
i. Digital: fingers/toes
j. Femoral: thigh
k. Frontal: forehead
l. Inguinal: groin
m. Mammary: breast
n. Mental: chin
o. Nasal: nose
p. Oral: mouth
q. Orbital: eye socket
r. Patellar: kneecap
s. Pelvic: pelvis
t. Fibular: side of leg
u. Pubic: genital region
v. Sternal: breast bone
w. Tarsal: ankle
x. Thoracic: chest
y. Umbilical: navel
2. Posterior –
a. Acromial: point of shoulder
b. Calcaneal: heel of foot
c. Cephalic: head
d. Dorsum: back
e. Gluteal: buttocks
f. Lumbar: back between ribs & hips
g. Manus: hand
h. Occipital: base of skull
i. Olecranal: posterior of elbow
j. Otic: ear
k. Plantar: sole of the foot
l. Popliteal: back of knee
m. Sacral: between hips on back
n. Scapular: shoulder blade
o. Sural: calf (back of leg)
p. Vertebral: spinal column
E. Body Planes:
1. to see internal structure of organs
2. refers to any slice or cut through a three-dimensional structure,
allowing us to visualize relationships between those parts. CT and
MRI technology use these principles.
a. Sagittal: divides the body or organ vertically into R and L
i. Midsagittal: divides the body or organ vertically into
equal right and left parts
ii. Parasagittal: vertical division offset from midline
b. Frontal/Coronal: a vertical plane dividing the body or an
organ into anterior (front) and posterior (back) sections.
c. Transverse/Horizontal/Cross Section: a horizontal plane
dividing the body or an organ into superior (upper) and
inferior (lower) sections.
d. Oblique: a diagonal cut
VIII. Body cavities:
A. openings within the torso which contain organs, protect delicate organs
from accidental shocks and bumps, and permit the expansion and
contraction of organs without disrupting the activities of other organs.
B. Two Major Cavities
1. Dorsal cavity - located on the posterior/dorsal surface of the body
and surrounds the brain and the spinal cord. Crucial to protect and
encased in bone.
a. Cranial Cavity - The bones of the skull protect the brain.
b. Spinal (Vertebral) Cavity - formed by the vertebrae of
the spine and surrounds the spinal cord.
2. Ventral Cavity - located on the anterior/ventral surface of the
body which contains the chest and abdomen.
a. Thoracic Cavity - ventral cavity superior to the diaphragm
i. contains heart (pericardial cavity) and lungs (pleural
ii. protected by ribs
b. Abdominopelvic Cavity - the portion of the ventral cavity
inferior to the diaphragm.
i. Abdominal Cavity - The superior portion of the
abdominopelvic cavity.
- extends from the diaphragm to the superior
margin of the pelvic girdle.
- contains the organs called viscera which
include the stomach, spleen, liver, gallbladder,
pancreas, small intestine, and most of the large
ii. Pelvic Cavity - the inferior portion of the
abdominopelvic cavity
- surrounded by pelvic bones.
- contains the urinary bladder, cecum,
appendix, sigmoid colon, rectum, and the male
or female internal reproductive organs.
C. Abdominopelvic cavity is so large that it is divided into regions
1. Quadrants divide the abdominopelvic cavity into four sections
using the belly button as the point of reference for both the
horizontal and vertical lines.
a. Right upper quadrant (RUQ)
b. Left upper quadrant (LUQ)
c. Right lower quadrant (RLQ)
d. Left lower quadrant (LLQ)
2. A more precise method of division is abdominal regions, dividing
the area into a tic tac toe board
a. Epigastric: above the stomach
b. Umbilical: neat the umbilicus or belly button
c. Hypogastric: below the stomach
d. L and R Hypochondriac: below the ribs
e. L and R Lumbar: near the large bones of the spinal cord
f. L and R Iliac/inguinal: near the groin
D. Other cavities:
1. Oral/digestive cavity
2. Nasal Cavity
3. Orbital cavities: encloses eyeball
4. Middle ear cavities: tiny bones, transmit sound to hearing
5. Synovial cavities: freely movable joint cavities
a. enclosed by a fibrous capsule.
b. Lined with synovial fluid and cartilage
E. Membranes of Cavities:
1. Walls of cavities surrounded by
a. Double layered membrane (serous or serosa)
- Parietal serosa lines cavity wall
- Visceral serosa-lines organs
- Fluid between reduces friction (important for mobile
organs, like heart)
2. Serous Membranes have specific names
a. Examples
- Parietal Pericardium (heart) and Visceral
- Abdominal membranes: peritoneum
- Lungs: pleura

Chapter 1 Lecture: The Human Body – An Orientation