Chapter One
The Scope of
Biology
Global to Microscopic
• Bio = Life Ology = the study
• Biology – natural science that is
the study of living things on a
global scale of the entire planet
down to the microscopic world
Large to Small
•Biosphere – all the
parts of the planet that
are inhabited by living
things (land, water,
atmosphere)
• Ecosystem – community of
living things and the
environment that supports them
(plants, animals, air, water, and
sunlight)
–Ecosystems are very diverse
and dynamic (changing)
Desert Marsh Pond
Rainforest
–All ecosystems
combined make
up the
biosphere
Large to Small
• Organism – Individual living
thing
–Different types of organisms
within their environment make
up an ecosystem
• Cell – basic units of structure
and function within an
organism
–Organisms are made up of
one or more cells
•Unicellular – single cell
•Multicellular – many cells
Large to Small
• DNA and Genes
–DNA – molecule responsible for
inheritance
• Instructs cell to make all
important molecules
–Gene - hereditary
segment for
a single trait
Life’s Diversity
• Life is very diverse; it contains
thousands of different species
–Species – a distinct form of life
• Insects are the most diverse
group of animals
Canis familiaris
Canis lupus
Classification
• Classification is needed
because life is so diverse
and there are so many
different kinds of organisms
–Classification – organizing
similar species into larger
groups
The Three Domains of Life
• Domain – Broadest
category of
classification
–Archaea
–Bacteria
–Eukarya
The Three Domains of Life
• Kingdoms – category of classification
after domains
–4 kingdoms within Eukarya domain
• Animals, Plants, Fungi, Protists
–1 kingdom within Archaea domain
• Archaebacteria
–1 kingdom within the
–Bacteria domain
The Three Domains of Life
• Archaea and
bacteria domains
contain very small
and simple
organisms;
unicellular and
prokaryotic cells
–Prokaryotic –
cells without
nuclei
• The Eukarya domain
contains more complex
organisms; most are
multicellular and have
eukaryotic cells
–Eukaryotic – cells with
a nuclei
Ten Unifying Themes of Life
• 1. Biological
Systems
• System – complex organization
formed from a simpler combination
of parts
–Made up of levels
of organization
Atom-molecule-cell-tissue-organorgan system- Organism
• Applies to all levels of life:
Biosphere – cells
Ten Unifying Themes of Life
• 2. Cellular
Basis of Life
–All living things are made up of
cells and have levels of
organization.
Ten Unifying Themes of Life
• 3. Form
and Function
–Form is unique to its
function
•Ex. The shape of a
bird’s wings = fly
•Nerve cell has long
fibers = send
messages
Ten Unifying Themes of Life
• 4. Reproduction
and Inheritance
– Inheritance is passed through
reproduction
– Genes contain DNA which carries
information for certain characteristics
– During cellular division, DNA is copied
– Egg (mom DNA) fuses with sperm (dad
DNA)
• Creates individual with
• some inherited traits
Ten Unifying Themes of Life
• 5. Interaction
with the
Environment
–All organisms interact with
its environment
•Photosynthesis-process
by which plants make
food)
–We depend on oxygen
Cellular respiration
– process by which
animals use food to
create energy
Plants depend on
carbon dioxide
•
Ten Unifying Themes of Life
6. Energy and Life
–All life processes
require energy
• Energy - the ability to
do work
–Energy flow within and
ecosystem
–Sunlight – producers consumers
• Energy then exits as
heat
–Producers (autotrophs) produce own food
–Consumers (heterotrophs)
– organisms that can not
make their own food and
depend on other
autotrophs or heterotrophs
Ten Unifying Themes of Life
• 7. Regulation
–Homeostasis - the ability of
an organism to keep
conditions inside the body
constant
•(sweating,
•shivering)
•
Ten Unifying Themes of Life
8. Adaptation and Evolution
–Living things adapt
•Adaptation - any
characteristic
or change that
helps the organism
survive or live successfully
in its environment
• Population – localized group of
organisms belonging to the
same species
• Natural Selection - process by
which individuals that are better
adapted to their environments
survive and reproduce more
successfully than less well
adapted individuals do
Evolution – change through time
Ten Unifying Themes of Life
• 9.
Biology and Society
–Biology is everywhere in society
Why is Biology important?
–1. Medicine (Avian Bird Flu)
–2. Agriculture (Growing
genetically engineered food)
–3. Industry (Use of bacteria to
break down sewage: efficiency)
•
Ten Unifying Themes of Life
10. Scientific Inquiry
–Because Biology is a science,
there is a reliance on certain
processes of inquiry
–Scientific Method - an
organized approach to help
understand how the natural
world works