Neil A. Campbell • Brad Williamson • Robin J. Heyden
Created by Roxanne Leitner
CONCEPT 1.1 Biology explores life from
the global to the microscopic scale.
Objectives
• Identify the major organizational levels of
life.
CONCEPT 1.1 Biology explores life from
the global to the microscopic scale.
Key Terms
• biosphere
• ecosystem
• organism
• cell
• DNA
• gene
Biosphere
• all parts of the planet
that are inhabited by
living things
• atmosphere
• lithosphere
• hydrosphere
• Flying foxes are becoming an endangered
species, partly because of habitat
destruction
Life in the Trees
• The lives of gray-headed flying foxes are
closely entwined with the lives of the
eucalyptus trees that form their habitat
• Eucalyptus trees
provide food and
roosting sites for
the flying foxes
• Flying foxes aid in
eucalyptus pollination
and help disperse
the resulting seeds
The Scope of Biology
• Biology is the scientific study of life
• Interactions between different kinds of
organisms affect the lives of all
Life’s levels of organization define the
scope of biology
• A structural hierarchy of life, from molecules
•
to ecosystems, defines the scope of biology
An ecosystem consists of:
• all organisms living in a particular area
• all nonliving physical components of the
environment that affect the organisms
(soil, water)
Ecosystem
• Ecosystems
ECOSYSTEM LEVEL
Eucalyptus forest
include:
• all the organisms
in an area, which
make up a
community
• interbreeding
organisms of the
same species, a
population
COMMUNITY LEVEL
All organisms in
eucalyptus forest
POPULATION LEVEL
Group of flying foxes
ORGANISM LEVEL
Flying fox
Brain
ORGAN SYSTEM LEVEL
Nervous system
ORGAN LEVEL
Brain
Spinal cord
Nerve
TISSUE LEVEL
Nervous
tissue
CELLULAR LEVEL
Nerve cell
MOLECULAR LEVEL
Molecule of DNA
Figure 1.1
Organism
• Organisms are
ECOSYSTEM LEVEL
Eucalyptus forest
made up of:
• organ
systems
• organs
• tissues
• cells
• molecules
• atoms
COMMUNITY LEVEL
All organisms in
eucalyptus forest
POPULATION LEVEL
Group of flying foxes
ORGANISM LEVEL
Flying fox
Brain
ORGAN SYSTEM LEVEL
Nervous system
ORGAN LEVEL
Brain
Spinal cord
Nerve
TISSUE LEVEL
Nervous
tissue
CELLULAR LEVEL
Nerve cell
MOLECULAR LEVEL
Molecule of DNA
Figure 1.1
Concept Check 1.1
1. Which level of life includes all of the other
levels in this list: organisms, cells,
biosphere, molecules, ecosystems?
Explain your answer.
biosphere
2. Identify an ecosystem in the area where
you live?
Concept Check 1.1
3. What are genes? How are they related to
DNA?
genes – units of inherited information
part of DNA molecule
CONCEPT 1.2 Biology explores life in its
diverse forms.
Objectives
• Use the term species in discussing life’s
diversity.
• Explain the basic strategy biologists use in
classifying organisms.
• Identify a characteristic that separates the
domains Bacteria and Archaea from the
domain Eukarya.
CONCEPT 1.2 Biology explores life in its
diverse forms.
Key Terms
• species
• domain
• unicellular
• prokaryotic cell
• eukaryotic cell
• multicellular
Classifying Life: The Basic Idea
taxonomy
• study of classification
species
• organisms that look
alike, can interbreed &
produce fertile
offspring
Levels of Classification
•
•
•
•
•
•
•
Kingdom
Phylum
Class
Order
Family
Genus
Species
Three Domains
• unicellular
• prokaryotic cells – without nuclei or membranebound organelles
1. Domain Bacteria
•
Typical bacteria
2. Domain Archaea
•
live in harsh environments
Figure 1.4A, B
3. Domain Eukarya
• unicellular or
•
multicellular
eukaryotic cells
• nucleus
• membrane-bound
organelles
• Kingdoms
• Protista
• Fungi
• Plantae
• Animalia
Figure 1.4C-F
Concept Check 1.2
1. Explain the relationship between the terms
species and organism.
2. Explain two different ways that you could
classify the following items: banana,
lemon, sandwich, milk, orange, meatball,
salad.
Concept Check 1.2
3. Explain the main difference between
organisms of the domains Bacteria and
Archaea and organisms of the domain
Eukarya.
Bacteria, Eukarya – prokaryotes
Eukarya - eukaryotes
CONCEPT 1.3 Ten Themes unify the study
of life.
Objectives
• Identify the themes of biology.
CONCEPT 1.3 Ten Themes unify the study
of life.
Key Terms
• systems
• photosystem
• producer
• consumer
• homeostasis
• adaptation
• population
• natural selection
• evolution
Unity in diversity: All forms of life have
common features
• All organisms share a set of common
features, signs of unity in life’s vast diversity
• All are made of cells
• All have DNA as
their genetic
blueprint
• These orchids show
the variety possible
within one species
Figure 1.5A
• DNA is made of chemical units called nucleotides
• Each species has its own nucleotide sequence
Figure 1.5B
• The genetic information in DNA underlies all
of the features that distinguish life from
nonlife
• Order and regulation
• Growth and development
• Use of energy from the environment
• Response to environmental stimuli
• Ability to reproduce
• Evolutionary change
Evolution explains the unity and diversity
of life
• Charles Darwin is a central figure in biology
• He synthesized the theory of evolution by
natural selection
• A theory in science is a
comprehensive idea with
broad explanatory power
• Evolution is the core theme
of biology
Figure 1.6A
Natural Selection
• The theory of
natural selection
explains the
main
mechanism
whereby all
species of
organisms
change, or
evolve
(1) Population with varied inherited traits
(2) Elimination of individuals with certain traits
Figure 1.6B
(3) Reproduction of survivors
• Evolution happens when populations of
organisms with inherited variations are
exposed to environmental factors that favor
the success of some individuals over others
• Natural selection is the editing mechanism
• Evolution is based on adaptations
Concept Check 1.3
1. Using examples describe three biology
themes.
2. Describe four ways you have interacted
with your environment today.
Concept Check 1.3
3. In biological terms are you a producer or
consumer? Explain your answer.