What is Life?
Living Things
 What are the requirements to be called a living thing?
Sometimes nonliving things have some living characteristics,
Must have ALL characteristics to be considered living
The Characteristics of Life

Living and nonliving things
share common characteristics,
such as being composed of
atoms, the smallest units of
natural substances.
1. Cellular Organization
 All Living things are composed of cells
2. Reproduction
 All living things reproduce
 Every living things goal is to…
Pass on its genes
Essential for the
continuation of the species
3. Grow and Develop
 Goes along with reproduction
 Must go from egg to breeding adult to be able to
pass on genes
 Goes through stages
4. Homeostasis
 Maintenance of a stable internal environment
 Regulation of
Body temperature
water
vitamins
food
energy
minerals
5. Metabolism
 All living things use energy
 Ability to break down food for use to make
energy
 “Respiration”
Taking a food molecule with oxygen and making
energy and carbon dioxide
Food + O2 = ATP (energy) + CO2
6. Heredity
 All living things contain genetic information in
DNA
 The transmission of genetic information from
parent to offspring is heredity
Other characteristic that living things
show
 Complexity
 Movement
 Sensitivity
 Adaptation
 Death
The Human Body:
An Orientation
The Human Body – An
Orientation
• Anatomy – study of the structure
and shape of the body and its parts
• Physiology – study of how the body
and its parts work or function
Anatomy – Levels of Study
• Gross Anatomy
• Large structures
• Easily observable
Anatomy – Levels of Study
• Microscopic Anatomy
• Very small
structures
• Can only be
viewed with
a microscope
Life’s Organization

Life is organized on many levels.
Atoms and molecules are nonliving materials from
which all of nature is built.
Cells are organized into increasingly complex
levels: tissues >>> organs >>> organ systems >>>
organisms.
Organisms, in turn, form populations >>>
communities >>> ecosystems >>> biosphere.
Levels of Organization in Nature
Levels of Organization in Nature
Organ System Overview
• Integumentary
• Forms the external body
covering
• Protects deeper tissue
from injury
• Synthesizes vitamin D
• Location of cutaneous
nerve receptors
Organ System Overview
• Skeletal
• Protects and supports
body organs
• Provides muscle
attachment for
movement
• Site of blood cell
formation
• Stores minerals
Organ System Overview
• Muscular
• Allows locomotion
• Maintains posture
• Produces heat
Organ System Overview
• Nervous
• Fast-acting control
system
• Responds to internal
and external change
• Activates muscles and
glands
Organ System Overview
• Endocrine
• Secretes regulatory
hormones
• Growth
• Reproduction
• Metabolism
Organ System Overview
• Cardiovascular
• Transports materials
in body via blood
pumped by heart
• Oxygen
• Carbon dioxide
• Nutrients
• Wastes
Organ System Overview
• Lymphatic
• Returns fluids to blood
vessels
• Disposes of debris
• Involved in immunity
Organ System Overview
• Respiratory
• Keeps blood supplied
with oxygen
• Removes carbon dioxide
Organ System Overview
• Digestive
• Breaks down food
• Allows for nutrient
absorption into blood
• Eliminates indigestible
material
Organ System Overview
• Urinary
• Eliminates nitrogenous
wastes
• Maintains acid – base
balance
• Regulation of materials
• Water
• Electrolytes
Organ System Overview
• Reproductive
• Production
of offspring
Anatomical Position
• Anatomical
position- body
erect with feet
parallel and
arms at sides
with palms
forward.
The Language of Anatomy
• Special terminology is used to
prevent misunderstanding
• Exact terms are used for:
• Position
• Direction
• Regions
• Structures
Directional Terms
• Superior- toward head
• Inferior- toward feet
• Anterior- toward front
• Posterior- toward back
• Medial- toward midline
• Lateral- away from midline
Directional Terms
• Intermediate- between a medial and
lateral structure
• Proximal- closer to attachment
• Distal- farther from attachment
• Superficial- toward surface
• Deep- away from surface
Body Landmarks
• Anterior
• abdominal- body trunk
below the ribs
• axillary- armpit
• brachial- arm
• buccal- cheek
Body Landmarks
• Anterior
• carpal- wrist
• cervical- neck
• coxal- hip
• digital- fingers & toes
• femoral- thigh
Body Landmarks
• Anterior
• nasal- nose
• oral- mouth
• orbital- eye cavity
• patellar- front of knee
• pelvic- area in front of
pelvis
• sternal- breastbone
Body Landmarks
• Anterior
• tarsal- ankle
• thoracic- chest
• umbilical- navel
Body Landmarks
• Posterior
• cephalic- head
• deltoid- curve of shoulder
• gluteal- buttock
• occipital- posterior surface
of head
Body Landmarks
• Posterior
• sacral- posterior surface
between hips
• scapular- shoulder blade
• vertebral- spinal column
Body Planes and Sections
• A section is a cut through the
body or an organ along an
imaginary line called a plane.
• Sagittal Section- lengthwise,
divides the body into left and
right parts.
• Midsagittal/Median Section:
when both sides are equal in
size.
Body Planes and Sections
• Frontal Section / Coronal Sectionlengthwise, divides the body into
anterior and posterior parts.
• Transverse Section / Cross
Section- horizontal, divides the
body into superior and inferior
parts.
Body Planes
Figure 1.6
Body Cavities
•Dorsal Body Cavity
•Cranial and Spinal cavities.
•Ventral Body Cavity
•Thoracic Cavity
•Diaphragm- thin muscle that separates
the thoracic and abdominopelvic cavities.
•Abdominopelvic Cavity
•Abdominal Cavity
•Pelvic Cavity
Body Cavities