6. Properties of Life
2. Metabolism
all living things process
energy which is used to
power other processes
The Flow of Energy
What would happen if
All decomposers
would disappear?
Energy moves from the sun
down the food chain
SUN
7. Energy Flows Through Ecosystems
• Much of the energy captured
by producers is lost as
energy passes through the
ecosystem
• 80% to 95% of the energy
available at one trophic level
is not transferred to the next
8. Properties of Life
3. Homeostasis
all living things maintain relatively stable internal
environments to optimize conditions for metabolism and
other processes
Dehydrated = less urination
Drank too much = more
urination
9. Properties of Life
4. Growth: living things increase in size
• Single cellular increase in size
until the divide into two
individuals = reproduction
• Multicellular increase their
number of cells by cell
division
10. Properties of Life
5. Reproduction: replicate or produce offspring
• Asexual reproduction:
cloning, binary, fission,
budding
• Sexual reproduction:
combining gametes
(sperm and egg)
14. • Living things are diverse
What are some examples of living things?
How do we decide which organisms are
placed in which groups?
15. • We can classify living things according to
Three Factors:
1. Their Size
2. Their Complexity
3. How they gain energy
Classification of Living Organisms
17. Terminology of Classification of living things
complexity
Prokaryotic cell
nucleoid
DNA is not bound by a membrane
Eukaryotic cell
nucleus
DNA IS bound by a membrane
18. Terminology of Classification of living things
energy use
Autotroph:
Produces its own energy
Heterotroph:
Must consume energy
19. (a) Domain Bacteria
(c) Domain Eukarya
2µm
(b) Domain Archaea
2µm
100 µm
Kingdom
Animalia
Kingdom
Plantae
Kingdom
Fungi Protists
Categorize the Diversity of Life
20. • Tardigrades, also known as “water bears”
microscopic animals capable of withstanding
some of the most severe environmental
conditions.
Kingdom: Animalia
http://www.popsci.com/water-bear-genome-holds-clues-to-its-survival-skills
21. The Organization of Life
• Living things function and interact with
each other on many levels
• The organization of life is a hierarchy of
levels of increasing complexity
cellular
organismal
populational
22. The Organization of Life
• At higher levels of the living hierarchy, new
properties become apparent that were absent at
the lower levels
• These emergent properties result from the
interaction of diverse but simpler components
• Many higher order processes that are hallmarks
of life are emergent properties
metabolism
consciousness
26. Theories that Unify Biology as a
Science
• What is a Theory?
Universal Gravity is a theory, not a law
27. Theory and Certainty
• The term “theory” means different things
to different audiences
to scientists,
• a theory represents certainty and is a unifying
explanation for a broad range of observations
to the general public,
• a theory implies a lack of knowledge or guess
28. • A well-substantiated explanation of some aspect
of the natural world,
• that is acquired through the scientific method
and repeatedly tested,
• and confirmed through observation and
experimentation
What is a Theory?
29. What is a Theory?
• Scientists’ acceptance of theory is
provisional
the possibility always remains that future
evidence will cause a theory to be revised
30. Theories that Unify Biology as a
Science
• 1. The Cell Theory
• 2. The Gene Theory
• 3. The Theory of Heredity
• 4. The Theory of Evolution
32. The Gene theory
DNA: Deoxyribonucleic Acid
Universal – All life uses the same 4 bases.
the difference between life forms is the sequence of the bases
Four
Nitrogenous
Bases
Adenine
Thymine
Guanine
Cytosine
33. DNA – Universal Code
GFP from Jellyfish inserted into Mouse DNA
34. Every cell of an organism contains the same set of genes;
the difference in tissue thype is, which genes are activated
Ectopic eye
on leg
Ectopic set of
wings
Ectopic legs
where antenna
should be
Ectopic gene
expression
Inappropriate
activation of
genes
35. The Theory of Heredity
Goldie Hawn and daughter Kate Hudson
36. The Theory of Heredity
• genes are passed down generations as discrete
units
37. The Theory of Evolution
• Charles Darwin’s explained:
the unity and diversity of life as “descent with modification”
Species living today
arose from ancestors
that differed from them
38. The Theory of Evolution
• Evolution is genetic change in a species over time
the diversity of life is explained by evolutionary processes
• the mechanism for evolution is natural selection
39. Natural Selection
Organisms well suited for survival in its
environment will thrive and pass those traits down
to their offspring
Herbert Spencer
Survival of the fittest
Evolution is more that JUST survival of
the fittest.
Over multiple generations those with
“good” genes will out-compete those
without these genes
40. Eye color is inherited from parents to offspring.
Would Tiny’s permanently change in eye affect the color of
her children’s eyes?
41. Natural Selection
Peppered Moths
white and black
Prior to industrial revolution
Trees were covered with lichen
• 99% were white moths
• Black moths visible and eaten
by birds
Following industrial revolution
Lichen killed; Smoke darkened
trucks
• 90% were dark moths
• White moths visible and eaten by
birds
42.
43. evolution favors structures that function in an
adaptive manner
many structures are specialized for a particular
function
Structure Determines Function
44. Structure and function
• Bird feet differ according to function
Ducks webbed
feet to swim
Woodpeckers need to
grasp on to tree
trucks
Raptors capture
prey with feet
Perching birds need
to sit and lock on to
braches
