Chapter 1 AN INTRODUCTION TO THE HUMAN BODY
I.
Understanding the human body
A.
Anatomy: study of structure
1.
Gross: large body structures visible to the naked eye
2.
Cytology: cells
3.
Histology: tissues
4.
developmental: change in structure from conception to old age
5.
embryology : changes before birth
B.
Physiology: study of function
1.
neurophysiology
2.
renal physiology
3.
cardiovascular physiology
4.
etc. by the various systems of the body
C.
Principle of Complementarity
1.
structure often determines function
D.
Hierarchy of Structural Organization
Structural levels:
1.
Chemical
a.
Atoms and molecules (chapter 2)
2.
Cell
a.
the living structural and functional unit
b.
ex. a muscle cell (also called muscle fiber)
3.
tissue
a.
groups of similar cells
b.
ex. cardiac muscle made up of many muscle cells
4.
organ
a.
two or more tissues that perform a function
b.
ex. heart: cardiac muscle and endothelium lining
5.
organ systems
a.
several organs to perform a function
b.
ex. cardiovascular system includes heart,
blood
vessels, nerves and requires
assistance
from lungs and kidneys
6.
Organism
a.
sum of all levels
b.
ex. individual
REVIEW ORGAN SYSTEMS IN LAB
E.
Classification of a living system
1.
Movement
a.
contraction of muscle
2.
Reproduction
a.
produce offspring to continue the species through reproductive system
3.
Responsiveness
a.
sense changes and respond to the environment
b.
nervous system, endocrine system (hormones)
4.
Metabolism
a.
sum of all chemical reactions or activities in the body
b.
catabolic reactions: break down
c.
anabolic reactions: build up
d.
includes:
1.
respiration
a. to generate ATP (body’s energy
source) by breaking down nutrients (Cellular respiration)
b.
also refers to gas exchange
5.
other processes associated with metabolism
a.
ingestion or taking in food
b.
digestion or breaking down food
c.
excretion or removal of wastes
d.
growth by building up reactions
e. differention of unspecialized cells developing into a specialized cells or tissue
F.
Homeostasis
1.the
cell's ability to maintain a stable internal
environment in face of a changing external environment
2.Maintains
a dynamic balance (always changing as compared to static)
3.Involves
communication
a.
nervous system and endocrine system (hormones)
b.
this is being responsive and integrates the information to maintain
homeostasis by:
1.
control center: areas of the brain
2.
receptor: sensor to monitor the environment
3.
effector: organ that responds
SIGNAL
> RECEPTOR > CONTROL CENTER > EFFECTOR
4.
Examples of homeostasis
a.
negative feedback
1.
response is in opposite direction of signal
b.
body fluid levels
1.
intracellular fluid
ICF
2.
extracellular fluid
ECF
a.
interstitial fluid
3.
cells must regulate
volume of fluid for normal function
4.
thirst, urination
c. blood pressure
1. high signal at a receptor and the response
will lower
2. low signal response is to
increase
d.
blood sugar
1.
high signal response is to lower
2.
low signal response to raise
e. positive feedback is unusual in homeostasis
1.
response is in
direction of signal
2.
example: release of
oxytocin (hormone) to increase
contractions
during labor
c. homeostatic
imbalances
1.
occur with diseases and aging
2.hypertension
can be improper functioning of
negative feedback system to regulate BP
II. Anatomical terminology
A.
Standard Anatomical Position
1.
body standing erect
2.
palms forward
3.
thumbs out
B.
Directional terms
1.
to describe where one body part is in reference to another
a.
distal : far
b.
proximal : near
c.
lateral : to the side
d.
intermediate : between
e.
medial : closer to the middle of the body
f.
anterior, ventral : front
g.
posterior, dorsal : back
h.
inferior : below
i.
superior : above
j.
superficial : near the surface
k.
deep : below the surface
C.
Regional terms
1.
axial
a.
main axis
2.
appendicular
b.
appendages or limbs
D.
Planes divide body into portions
1.
sagittal: longitudinal Right/left
2.
midsagittal : down midline right = left
side
3.
parasagittal : not = right and left sides
4.
frontal (coronal): longitudinal plane divides body into anterior and posterior
portions
5.
transverse (horizontal): inferior and superior
6.
oblique : at an angle
E.
Body Cavities
1.
Dorsal body cavity : posterior divided into
a.
cranial cavity ( brain)
b.
vertebral cavity ( spinal cord)
2.Ventral
body cavity: houses internal organs divided into thoracic and abdominopelvic
cavities:
a.
thoracic cavity
divided
into:
1.
pleural cavity (lungs)
2.
mediastinum
a.
pericardial cavity (heart)
b.
thoracic organs (esophagus,trachea,etc)
b.
abdominopelvic cavity divided into:
1.
abdominal cavity
a.stomach,
intestines, liver,etc.
2.
pelvic cavity
b.bladder,reproductive
organs
c.
diaphram separates thoracic and abdominopelvic cavities
d.
ventral cavity wall covered with a double serous membrane
1.
parietal serosa : covers wall
2.
visceral serosa covers organs
3.
serous fluid fills space between the two membranes
a.
fluid decreases friction on the moving organ
4.
The pericardium is the membrane surrounding the heart in
the thoracic
cavity and has a parietal and visceral serosa.
3.
Other cavities
a.
oral
b.
nasal
c.
orbital
d.
synovial (fluid filled cavity around a joint)
F.
Location of organs in the abdominopelvic cavity
1. 9 regions
rt
hypochondriac epigastric lt hypochondriac
rt.
lumbar umbilical lt
lumbar
rt.
iliac hypogastric lt iliac (inguinal)
2. Quadrants (most commonly used regions of
abdominopelvic cavity)
RUQ LUQ
RLQ LLQ