Unit 3
Why is it important for environmentalists to
understand how organisms are organized?
 Every organism is a chemical factory that
captures matter & energy from its
environment and transforms them into
structures & processes that make life
possible…
 We are learning Atoms …… Biosphere
Levels of Organization
All elements are composed of one type of atom:
I. Atoms (the smallest particles that exhibit the
characteristics of the element) are made of
subatomic particles:
a. Protons (+) in the nucleus
b. Neutrons (0) in the nucleus
Give atoms
their weight
c. Electrons (-) outside the nucleus in electron cloud
Dot diagram - shows valence electrons
Bohr Model of nitrogen
Levels of Organization
II. Compounds: substances composed of different
kinds of atoms
Levels of Organization
II. The Four Organic Compounds that make up bio-
compound in cells:
1.
Lipids: fats & oils

Store energy & make up cell membrane
Carbohydrates: sugars, starches, & cellulose
2.

Store energy & provide cell structure
Proteins: amino acids
3.

Structure, enzyme, immunity
Nucleic acids: DNA & RNA (made of sugar,
phosphate group, & nitrogen base)
4.

Store & express genetic information
Create a graphic organizer for
the four macromolecules.
 Be sure to include:
1. Name of Macromolecule
2. Function of Macromolecule
3. What are they made up of? (nucleotides,
sugars, etc)
4. Examples! (eggs, cell membrane, fruit,
etc)
3. Bacteria
To Be Turned In:
Draw, color, and label the
three cell types & their
internal structures/
organelles
I. Atoms
II. Compounds
III. Cells
Types of Cells
 Prokaryotic cells: have no nucleus or
membrane-bound organelles
 Seen in bacteria
Types of Cells
 Eukaryotic cells: have a nucleus & organelles bound by
membrane
 Seen in plants, animals, fungi, and protists
 Organelles = tiny organs inside cell
 Nucleus: house for DNA
 Mitochondria: “power house”; performs respiration (makes
energy from sugar)
 Chloroplast: in plants only; performs photosynthesis (make
sugar from sunlight)
 Ribosomes: make protein
 And more…
Levels of Organization
6 Kingdoms
Prokaryotes/ Bacteria: (have no nucleus or membranebound organelles):
1. Archaebacteria Kingdom: “extreme” prokaryotes

Found in hot springs, deep sea, sulfur springs
2. Eubacteria Kingdom: general prokaryotes

Found everywhere!
 Important Note:
Bacteria act as decomposers
Levels of Organization
Eukaryotes: (have nucleus & membrane-bound
organelles):
3. Fungi Kingdom: eukaryotic multicellular absorptive
*heterotrophs (eat others for food)
4. Protist Kingdom: eukaryotic single- and multi-celled
*autotrophs (make own food) & heterotrophs
5. Plant Kingdom: Eukaryotic multicellular autotrophs
 4 Types:




Mosses
Ferns
Gymnosperms (i.e. conifers): seeds are not in flowers/fruits
Angiosperms : flowering plants that produce seeds in flower/fruit
6. Animal Kingdom: Eukaryotic multicellular heterotrophs
 2 Types:


Invertebrates: animals without spines
 Examples: Jellyfish, coral, sponges, insects, worms
Vertebrates: animals with spines; 5 main types:
 Fish, amphibians, reptiles, birds, mammals
organized into
higher levels.
 Organisms can be
Levels of Organization
Levels of Organization
Population: same species living in an area


Species = group of similar organisms that can
interbreed
Example: all the Giant pandas in a forest
Community: group of different populations living in
same area

Example: All the different plants & animals in a forest
Levels of Organization
Ecosystems: area where living (biotic) & nonliving
(abiotic) things interact
 Where plants & animals interact with each other &
the water, soil, wind, sunlight
Levels of Organization
Biome: Ecosystems with similar climates and
communities

Example: forest, desert, grassland
Biosphere: (Ecosphere)- all ecosystems of the
earth



Hydrosphere: water portion of Earth
Lithosphere: rock/ ground portion of Earth
Atmosphere: air portion of Earth
Ecosystem Pyramid
 Choose an organism and
illustrate a pyramid
about the organism
 Include biosphere,
biome, ecosystem,
community, population,
and species.
 Provide a
definition/description
of each level
 See example for
assistance 
Classifying Organisms
 Classification: The
process of putting
similar things into
groups
 Taxonomy: the science
of classifying organisms
 Organisms are classified
into Domains  Species
Classifying Organisms
 Three Domains:
1. Archaea

Archaebacteria Kingdom
2. Bacteria

Eubacteria Kingdom
3. Eukaryota
 Plant Kingdom
 Fungi Kingdom
 Protist Kingdom
 Animal Kingdom
Classifying Organisms
Domain
 Kingdom (king)
 Phylum (phillip)
 Class (came)
 Order (over)
 Family (for)
 Genus (grape)

Species (soda)
 Binomial nomenclature is
used – Genus species
 All organisms given two
names
Human Taxonomy
 Kingdom Animalia
 Phylum Chordata
 Class Mammals
 Order Primates
 Family Hominid
 Genus Homo
 Species Sapiens
 Homo sapiens
The Theory of Natural Selection
by Evolution
 Evolution = The change in organisms
over time
 Important: populations change, not
individuals
 Evolution occurs by Natural Selection
 Theorized by Charles Darwin
Natural Selection: The Steps
1. Genetic diversity in pop. Some individuals have traits
better suited for the environment.
2. Individuals with advantageous traits survive longer &
make more offspring.
3. Advantageous traits get passed on to the next generation
(next set of offspring)
4. Over time, more individuals have these advantageous
traits (adaptation)  evolution
ADAPTATION= trait that helps
organisms survive in their
environment
Can be physical, physiological,
behavioral, combo.
Environmental Science & Evolution
Antibiotic resistance = bacteria develop
resistance to antibiotics through natural
selection.
The steps:
Environmental Science & Evolution
•Widespread use of antibiotics in
medicines, household products & farming
has lead to resistant bacteria!
•Examples include E. coli and MRSA
(Methicillin-resistant Staphylococcus
aureus)
Environmental Science & Evolution
Pesticide Resistance = pests develop
resistance to chemicals through natural
selection