Transcript Day 25 – Carbohydrates

 HAPPY THURSDAY 
Bellwork: How many bright stars do you see on each
square? Black stars on each square? What is this an
example of?
Peppered moths are eaten by birds. The moth color varies from
light to dark. Light colored moths can blend in with a nearby
species of tree. In the 1800s factories released large amounts
of soot, which changed the tree color, so the birds were able
to more easily find the lighter moths instead of the darker
moths.
Standard: (7E)Analyze and
evaluate relationship of natural
selection to adaptation.
Essential Question: What is
evolution?
Quiz tomorrow –
Vocabulary and
Notes
HW: Evolution Practice
Search for the YouTube video “Evolution
Practice”
by Alyssa Dolny.
PreAP: Complete on Page 42 of your I.A.N.
using Cornell Notes. Due on Friday.
Periods 4 & 5: Complete on Page 45 of your
I.A.N. using Cornell Notes. Due on Friday.
Summary of Darwin’s Theory:
 Individual organisms differ and some of these variations are
heritable (passed on)
 Organisms produce more offspring than can survive and
many that do survive do not reproduce
 Because more organisms are produce than can survive, they
must compete for limited resources (food, shelter, etc)
 Each unique organism has different advantages (good) and
disadvantages (bad)
 Individuals best suited to their environment survive and
reproduce successfully
 These organisms that survive pass their heritable traits to
their offspring
Summary of Darwin’s Theory cont’d:
 Other individuals that are not suited for their
environment die or leave few offspring
 This process called natural selection causes species
to change over time
 Species alive today are descended with modification
from ancestral species (their ancestors)
 This process by which diverse species evolved from
a common ancestor unites all organisms on Earth
into a single tree of life
One of Darwin’s most
important insights was
that members of each
species vary from one
another in important
ways.
Today, we know that
heritable variation in
organisms is caused by
variations in their genes.
II. How Evolution Works
A. Artificial selection: selection by humans for
breeding of useful traits
1. The struggle for existence is
competition among
members of a species for
food, living space, and
the other necessities of life.
2. High birth rates and a
shortage of life’s basic
needs eventually forces
organisms into a
competition for resources.
B. Fitness: the ability of an organism to survive and
reproduce
1. Fitness is the result of adaptations.
2. Adaptation: any inherited characteristic that
increases an organism’s chance of survival.
a. Successful adaptations:
- enable organisms to become better suited to
their environment
- increase an individual’s ability to survive and
reproduce.
Humans have thousands of adaptations: large brain,
opposable thumbs, excellent sensory organs, light,
strong skeleton, etc.
C. Natural selection: the process by which individuals with
characteristics that are not well suited to their
environment either die or leave few offspring.
1. Also referred to as survival of the fittest.
2. It is not seen directly, but only observed as changes
in a population over a long time.
3. Zombieland: The Rules
A. Descent with modification: a
principle that says each living
species has descended, with
changes, from other species
over time.
1. It implies that all living
organisms are related
2. Also known as common
descent.
3. States all species were
derived from common
ancestors.
B. Darwin found evidence in:
1. the fossil record
2. the geographical distribution of living species (Biogeography)
3. homologous structures of living organisms
4. similarities in early development, or embryology.
C. Scientists use the fossil record
to help determine evolutionary
changes.
By comparing fossils from older
rock layers with fossils from
younger layers, scientists could
document the fact that life on
Earth has changed over time.
Researchers have discovered
many hundreds of transitional
fossils that document various
intermediate stages in the
evolution of modern species from
organisms that are now extinct.
Gaps remain in the fossil record. These gaps do not
indicate weaknesses in the theory of evolution itself.
Rather, they point out uncertainties in our
understanding of exactly how some species evolved.
D. Homologous structures: structures that have different
mature forms but develop from the same embryonic tissues
are called (start different, end similar)
E. Vestigial organs are organs that serve no
useful function in an organism.
Something Important to Know:
Theory: a well-supported scientific explanation that is
subject to change.
Law: a scientific fact.
Evolution is a theory.
Evolution is often called “the grand unifying theory of
biology.”
Evolutionary theory continues to change as new data are
gathered and new ways of thinking arise.