Chapter 1 – 1.1 Level of Organization
Chapter 1 – 1.3
Organization of Life?
What is Life?
Cells - the structural & functional Units of Life
The properties of life that arise from the structural level
of a cell illustrates an important theme in biology called
“emergent properties”
Define ecosystem
MULTICELLULAR ORGANISM
“The whole is greater than the
sum of its parts”
ORGAN SYSTEM
ORGAN
TISSUE
With each step upward in the
Hierarchy of biological
ordering new properties
Emerge as a result of I
interactions
CELL
ORGANELLE
MOLECULE
Cluster of atoms held
together by chemical bonds
ATOM
Chapter 1 – 1.3
What is Life?
Cells - the structural & functional Units of Life
Chapter 1
What is Life?
What are the Characteristics of Life?
Each level of biological organization exhibits
emergent properties.
Ex. Capillaries transport
blood (property not exhibited by
individual endothelial cells).
Organized into “organelles”
The properties of life that arise from the structural level
of a cell illustrates an important theme in biology called
“emergent properties”
Biological Themes in Living World
Evolution
Energy Flow
Cooperation
Structure/Function
Homeostasis
What is Science?
Two Broad Categories of Science
• Discovery Science
• Hypothesis -based Science
Reasoning
DEDUCTIVE
Generalizations ? specific conclusions
INDUCTIVE
Discovery Science
• Describing Nature
• Examples could range from sequencing a
the genetic makeup of a species to making a
list of animals and/or plants that live in a
defined region (e.g., Furman’s campus, a
state park, a national park or an entire ecoregion.
Discovery Science
By means of “inductive reasoning”, discovery
science can lead to important conclusions
(e.g., when “old growth” southern pines are
removed the listed red-cockaded
woodpecker disappears.)
Events ? Generalizations
Hypothesis-Based Science
Hypothesis-Based Science
Discovery Science stimulates inquiring minds
to ask questions and seek explanations.
A hypothesis is a “tentative” answer which is
on trial so-to-speak.
Deductive reasoning is the logic used to test
hypothesis
Hypotheses must be “testable” and
“falsifiable”
Hypothesis: Mimics benefit
because predators confuse them
with harmful species
Case study: David and Karin Pfennig, UNC Chapel Hill
Eastern Coral Snake
King Snake
Eastern Coral Snake
Hypothesis: Mimicry should
protect the King Snake but only in
areas where Coral Snake occurs.
Eastern Coral Snake
Scarlet King Snake
These two species both live in the
Carolinas of the Southeast US
but the king snake’s range extends
further
predators
How do we study the Natural World?
Scarlet King Snake
Researchers put over 1000 artificial snakes (colorful
banded and plain brown)
north
south
Fig 1.8E
Control group
This experimental design left coloration as the only factor
that would explain low predation on artificial king snakes
How do we study the Natural World?
What is difference between hypothesis, theory & law?
Observations
Question
Hypothesis - “an educated guess”; a tentative
explanation of phenomena.
Hypothesis
Prediction
Experiment
Theory - a widely accepted explanation of natural
phenomena; has stood up to thorough & continual
testing.
Law - a statement of what always occurs under
certain conditions.
How do we study the Natural World?
How is a control group different from an
experimental group?
Control group: Control groups are not manipulated. They are the
foundational point for which to compare the experimental
group against.
Four Theories Unify Biology as a Science
Experimental group: The group being treated, or otherwise
manipulated for the sake of the experiment. This group is
identical to the control group EXCEPT that it is manipulated.
Chapter 1 – 1.4
#1 – Cell Theory – all living things…
What is Life?
#2 Gene Theory – the basis of inheritance
Unit of Life – All forms of Life have common features
DNA!
#3 – The Theory of Heredity – chromosomes
inherited
#4 – Theory of Evolution
Chapter 1
What is Life?
Chapter 1
What are the Characteristics of Life?
All living things exhibit seven
characteristics in combination.
Chapter 1
What is Life?
What is Life?
What are the Characteristics of Life?
1. Order – complex organization
2. Regulation – maintain internal environment
3. Growth & Development – regulated by
inherited genetic information
4. Energy Utilization – take in energy & convert it
5. Response to the environment – responding to stimuli
6. Reproduction – all organisms reproduce their own kind
7. Evolution – species change over time – nature acts
on genetic variations
Chapter 1
Life is Diverse
What is Life?
Life is Diverse
Pronounced “R” – “key ” – “ahh”
Biodiversity refers to the many different types of
organisms on earth.
Taxonomy is the biological science that
classifies life according to evolutionary
relationships.
The Domain is the largest group of organisms.
Can not form spores and can use more
Compounds for energy (some use hydrogen gas!)
Chapter 1
What is Life?
Life is Diverse
Chapter 1
What is Life?
Life is Diverse
Human classification scheme:
Kingdom
Phylum
Class
Order
Family
Genus
Species
Kings Play Chess On Funny Green Squares
Domain
Kingdom
Phylum
Class
Order
Family
Genus & species
Eukarya
Animalia
Chordata
Mammalia
Primates
Hominidae
Homo sapiens