26
UNIT ONE
i. Assimilation—changing substances into
chemically different forms.
j. Excretion—removing body wastes.
2. Metabolism is the acquisition and use of energy by an
organism.
1.5
MAINTENANCE OF LIFE (PAGE 7)
The structures and functions of body parts maintain the
life of the organism.
1. Requirements of organisms
a. Water is used in many metabolic processes,
provides the environment for metabolic reactions,
and transports substances.
b. Nutrients supply energy, raw materials for building
substances, and chemicals necessary in vital
reactions.
c. Oxygen is used in releasing energy from nutrients;
this energy drives metabolic reactions.
d. Heat is part of our environment and is a product
of metabolic reactions; heat helps control rates of
these reactions.
e. Pressure is an application of force; in humans,
atmospheric and hydrostatic pressures help
breathing and blood movements, respectively.
2. Homeostasis
a. If an organism is to survive, the conditions within
its body fl
uids must remain relatively stable.
b. The tendency to maintain a stable internal
environment is called homeostasis.
c. Homeostatic mechanisms involve sensory
receptors, a control center with a set point, and
effectors.
d. Homeostatic mechanisms include those that
regulate body temperature, blood pressure, and
blood glucose concentration.
e. Homeostatic mechanisms employ negative feedback.
1.6
ORGANIZATION OF THE HUMAN BODY
(PAGE 12)
1. Body cavities
a. The axial portion of the body contains the cranial
cavity and vertebral canal, as well as the thoracic
and abdominopelvic cavities, separated by the
diaphragm.
b. The organs within thoracic and abdominopelvic
cavities are called viscera.
c. Other body cavities include the oral, nasal, orbital,
and middle ear cavities.
2. Thoracic and abdominopelvic membranes
Parietal serous membranes line the walls of these
cavities; visceral serous membranes cover organs
within them. They secrete serous fl
uid.
a. Thoracic membranes
(1) Pleural membranes line the thoracic cavity and
cover the lungs.
(2) Pericardial membranes surround the heart and
cover its surface.
(3) The pleural and pericardial cavities are
potential spaces between these membranes.
CHAPTER SUMMARY
1.1
INTRODUCTION (PAGE 3)
1. Early interest in the human body probably developed as
people became concerned about injuries and illnesses.
Changes in lifestyle, from hunter-gatherer to farmer to
city dweller, were refl ected in types of illnesses.
2. Early doctors began to learn how certain herbs and
potions affected body functions.
3. The idea that humans could understand forces that
caused natural events led to the development of
modern science.
4. A set of terms originating from Greek and Latin formed
the basis for the language of anatomy and physiology.
1.2
ANATOMY AND PHYSIOLOGY (PAGE 4)
1. Anatomy deals with the form and organization of
body parts.
2. Physiology deals with the functions of these parts.
3. The function of a part depends upon the way it is
constructed.
1.3
LEVELS OF ORGANIZATION (PAGE 4)
The body is composed of parts that can be considered at
different levels of organization.
1. Matter is composed of atoms, which are composed of
subatomic particles.
2. Atoms join to form molecules.
3. Organelles consist of aggregates of interacting large
molecules (macromolecules).
4. Cells, composed of organelles, are the basic units of
structure and function of the body.
5. Cells are organized into layers or masses called tissues.
6. Tissues are organized into organs.
7. Organs form organ systems.
8. Organ systems constitute the organism.
9. These parts vary in complexity progressively from one
level to the next.
1.4
CHARACTERISTICS OF LIFE (PAGE 6)
Characteristics of life are traits all organisms share.
1. These characteristics include
a. Movement—changing body position or moving
internal parts.
b. Responsiveness—sensing and reacting to internal
or external changes.
c. Growth—increasing in size without changing in
shape.
d. Reproduction—producing offspring.
e. Respiration—obtaining oxygen, using oxygen to
release energy from foods, and removing gaseous
wastes.
f. Digestion—breaking down food substances into
forms that can be absorbed.
g. Absorption—moving substances through
membranes and into body fl
uids.
h. Circulation—moving substances through the body
in body fl
uids.
previous page 56 David Shier Hole's Human Anatomy and Physiology 2010 read online next page 58 David Shier Hole's Human Anatomy and Physiology 2010 read online Home Toggle text on/off