Chapter 1
Introduction to Anatomy & Physiology
Overview of Anatomy and Physiology
Anatomy
the study of the structure of body parts and their relationships to
one another
Gross
or macroscopic
Microscopic
Developmental
Physiology
the study of the function of the bodys structural machinery
Gross Anatomy
Regional
all structures in one part of the body
(such as the abdomen or leg)
Systemic
gross anatomy of the body studied by system
Surface
study of internal structures as they relate to the overlying skin
Microscopic Anatomy
Cytology
study of the cell
Histology
study of tissues
Developmental Anatomy
Embryology
study of developmental changes of the body before birth
Physiology
Considers
the operation of specific organ systems
Renal
kidney function
Neurophysiology
workings of the nervous system
Cardiovascular
operation of the heart and blood vessels
Focuses
on the functions of the body, often at the cellular or molecular level
Physiology
Understanding
physiology also requires a knowledge of physics, which explains electrical
currents, blood pressure, and the way muscle uses bone for movement
Principle of Complementarity
Function
always reflects structure
What
a structure can do depends on its specific form
Levels of Structural Organization
Chemical
atoms combined to form molecules
Cellular
cells are made of molecules
Tissue
consists of similar types of cells
Organ
made up of different types of tissues
Organ
system consists of different organs that work closely together
Organismal
made up of the organ systems
Organ Systems of the Body
Integumentary
system
Forms
the external body covering
Composed
of the skin, sweat glands, oil glands, hair, and nails
Protects
deep tissues from injury and synthesizes vitamin D
Organ Systems of the Body
Skeletal
system
Composed
of bone, cartilage, and ligaments
Protects
and supports body organs
Provides
the framework for muscles
Site
of blood cell formation
Stores
minerals
Organ Systems of the Body
Muscular
system
Composed
of muscles and tendons
Allows
manipulation of the environment, locomotion, and facial expression
Maintains
posture
Produces
heat
Organ Systems of the Body
Nervous
system
Composed
of the brain, spinal column, and nerves
Is the
fast-acting control system of the body
Responds
to stimuli by activating muscles and glands
Organ Systems of the Body
Cardiovascular
system
Composed
of the heart and blood vessels
The
heart pumps blood
The
blood vessels transport blood throughout the body
Organ Systems of the Body
Lymphatic
system
Composed
of red bone marrow, thymus, spleen, lymph nodes, and lymphatic vessels
Picks
up fluid leaked from blood vessels and returns it to blood
Disposes
of debris in the lymphatic stream
Houses
white blood cells involved with immunity
Organ Systems of the Body
Respiratory
system
Composed
of the nasal cavity, pharynx, trachea, bronchi, and lungs
Keeps
blood supplied with oxygen and removes carbon dioxide
Organ Systems of the Body
Digestive
system
Composed
of the oral cavity, esophagus, stomach, small intestine, large intestine,
rectum, anus, and liver
Breaks
down food into absorbable units that enter the blood
Eliminates
indigestible foodstuffs as feces
Organ Systems of the Body
Urinary
system
Composed
of kidneys, ureters, urinary bladder, and urethra
Eliminates
nitrogenous wastes from the body
Regulates
water, electrolyte, and pH balance of the blood
Organ Systems of the Body
Male
reproductive system
Composed
of prostate gland, penis, testes, scrotum, and ductus deferens
Main
function is the production of offspring
Testes
produce sperm and male sex hormones
Ducts
and glands deliver sperm to the female reproductive tract
Organ Systems of the Body
Female
reproductive system
Composed
of mammary glands, ovaries, uterine tubes, uterus, and vagina
Main
function is the production of offspring
Ovaries
produce eggs and female sex hormones
Remaining
structures serve as sites for fertilization and development of the fetus
Mammary
glands produce milk to nourish the newborn
Organ System Interrelationships
The
integumentary system protects the body from the external environment
Digestive
and respiratory systems, in contact with the external environment, take in
nutrients and oxygen
Organ System Interrelationships
Nutrients
and oxygen are distributed by the blood
Metabolic
wastes are eliminated by the urinary and respiratory systems
Necessary Life Functions I
Maintaining
boundaries the internal environment remains distinct from the external
Cellular
level accomplished by plasma membranes
Organismal
level accomplished by the skin
Movement
locomotion, propulsion (peristalsis), and contractility
Responsiveness
ability to sense changes in the environment and respond to them
Digestion
breakdown of ingested foodstuff
Necessary Life Functions II
Metabolism
all the chemical reactions that occur in the body
Excretion
removal of wastes from the body
Reproduction
cellular and organismal levels
Cellular
an original cell divides and produces two identical daughter cells
Organismal
sperm and egg unite to make a whole new person
Growth
increase in size of a body part or of the organism
Survival Needs
Nutrients
chemical substances used for energy and cell building
Oxygen
needed for metabolic reactions
Water
provides the necessary environment for chemical reactions
Maintaining
normal body temperature necessary for chemical reactions to occur at
life-sustaining rates
Atmospheric
pressure required for proper breathing and gas exchange in the lungs
Homeostasis
Homeostasis
is the ability to maintain a relatively stable internal environment in an
ever-changing outside world
The
internal environment of the body is in a dynamic state of equilibrium
Chemical,
thermal, and neural factors interact to maintain homeostasis
Homeostatic Control Mechanisms
Variable
produces a change in the body
Receptor
monitors the environments and responds to changes (stimuli)
Control
center determines the set point at which the variable is maintained
Effector
provides the means to respond to the stimulus
Homeostatic Control Mechanisms
Negative Feedback
In
negative feedback systems, the output shuts off the original stimulus
Example: Regulation of blood glucose levels
Positive Feedback
In
positive feedback systems, the output enhances or exaggerates the original
stimulus
Example: Regulation of blood clotting
Homeostatic Imbalance
Disturbance
of homeostasis or the bodys normal equilibrium caused by disease
Overwhelming
of negative feedback mechanisms allowing destructive positive feedback
mechanisms to take over
Anatomical Position
Body
erect, feet slightly apart, palms facing forward, thumbs point away from the
body
Directional Terms
Superior
and inferior toward and away from the head, respectively
Anterior
and posterior toward the front and back of the body
Medial,
lateral, and intermediate toward the midline, away from the midline, and
between a more medial and lateral structure
Proximal
and distal closer to and farther from the origin of the body
Superficial
and deep toward and away from the body surface
e 1
Regional Terms
Axial
head, neck, and trunk
Appendicular
appendages or limbs
Specific
regional terminology
Body Planes
Sagittal
and medial divides the body into right and left parts
Midsagittal
sagittal plane that lies on the midline
Frontal
or coronal divides the body into anterior and posterior parts
Transverse
or horizontal (cross section) divides the body into superior and inferior
parts
Oblique
section cuts made diagonally
Body Cavities
Dorsal
cavity protects the nervous system, and is divided into two subdivisions
Cranial
cavity is within the skull and encases the brain
Vertebral
cavity runs within the vertebral column and encases the spinal cord
Ventral
cavity houses the internal organs (viscera), and is divided into two
subdivisions: thoracic and abdominopelvic
Body Cavities
Thoracic
cavity is subdivided into pleural cavities, the mediastinum, and the
pericardial cavity
Pleural
cavities each houses a lung
Mediastinum
contains the pericardial cavity, and surrounds the remaining thoracic organs
Pericardial
encloses the heart
The
abdominopelvic cavity is separated from the superior thoracic cavity by the
dome-shaped diaphragm
It
is composed of two subdivisions
Abdominal
cavity contains the stomach, intestines, spleen, liver, and other organs
Pelvic
cavity lies within the pelvis and contains the bladder, reproductive organs,
and rectum
Ventral Body Cavity Membranes
Parietal
serosa covering the body walls
Visceral
serosa covering the internal organs
Serous
fluid separates the serosae
Other Body Cavities
Oral
and digestive mouth and cavities of the digestive organs
Nasal
located within and posterior to the nose
Orbital
house the eyes
Middle
ear contain bones (ossicles) that transmit sound vibrations
Synovial
joint cavities
Abdominopelvic Regions
Umbilical
Epigastric
Hypogastric
Right
and left iliac or inguinal
Right
and left lumbar
Right
and left hypochondriac
Abdominopelvic Quadrants
Right
upper
Left
upper
Right
lower
Left
lower