Transcript Overproduction

Date
Session
#
3/7-8
8
Activity
Page
#
Hidden Organism
Evolution of life “recap”
Mouse Hunt
18
Genotype Phenotype Review
19
Conflicting Evolution Theories
Darwin’s 4 Principles
20
h/w read 17B-25B answer questions 1-5 on 25B
8.L.4 Understand the evolution of organisms and
landforms based on evidence, theories and
processes that impact the earth over time.
8.L.4.1 Summarize the use of evidence drawn from
geology, fossils, and comparative anatomy to form
the basis for biological classification systems and
the theory of evolution
8.L.4.2 Explain the relationship between genetic
variation and an organism’s ability to adapt to its
environment
TLW explain the principles of evolution by
relating each principle to an element of a
classroom demonstration, completing analysis
questions after viewing a video.
Hidden Organism p. 18
• You will have 1 minute to search the room for an
organism that “lives” in the classroom.
• Your are this organism’s predator.
• The organism is shaped like this:
• When you find it/them, TELL NO ONE!
• Return to your seat and describe this activity and
the adaptation of this species on 18 of your
notebook. Describe any other organisms you can
think of with this type of adaptation.
Geologic Time Scale records the evolution of life
Unicellular
organisms
(1 cell)
bacteria
Multicellular organisms
(2 or more cells)
Simple plants
ferns
algae
fish
amphibians
Flowering plants
reptiles
mammals
Evolution of living organisms: process thru which species change
over time, due to a change in genetic material that is passed thru
generations.
Mouse Hunt
Think and write…what did you notice?
Early conclusions?
Read and annotate
Genotype Phenotype review
• Genotype describes the genes/alleles an organism has inherited from its
parents. Organisms inherit one copy of each gene from their parents.
Genotypes are represented using letters for each allele (one from each
parent.) An allele is a form of a gene. (Ex: G and g are two alleles of a
gene. GG, Gg, and gg are the different genotypes for this trait). Capital
letters represent the dominant allele, lower case letters represent the
recessive allele.
• Phenotype describes how the genotype is expressed in an organism.
Phenotype is how an organism looks (physical traits) based on the
genotype. Different genotypes can produce different phenotypes for a
trait.
One sentence that summarizes the difference between a genotype and a phenotype
Right Handed
Brown Eyes
Straight hair
attached ear lobes
EE, Ee
Right Handed
Ccdd
CCdd
Blue Eyes
ee
Freckles
attached ear lobes
Right handed, Curly hair
EeDd, EE,Dd
EEDD, EeDD
Right handed, curly hair
Read and annotate
Genetics and Natural Selection
• Traits are controlled by genes, which are inherited during reproduction.
• A population can be thought of as a gene pool.
• Evolution through Natural Selection acts on an organism’s phenotype (traits or
characteristics) not its genotype. As a result, it influences the frequency of
genotypes. For many traits, the homozygous genotype (AA, for example) has
the same phenotype as the heterozygous (Aa) genotype. If both an AA and an
Aa individual have the same phenotype, the environment will not distinguish
between them.
• Some alleles (forms of a gene) can increase or decrease based on changing
selective pressures from the environment. (New disease, predator, climate
shift)
On page 19
• Write a one sentence summary about the
relationship between genotypes, phenotypes
and evolution
Page 20
Two scientists with competing theories of evolution
LAMARK
•French
•Animals acquired
traits during their
lifetime and passed
them on to offspring
•Lamark was wrong!!
•Ex. Giraffes
DARWIN
Two scientists with competing theories of evolution
LAMARK
•French
•Animals acquired
traits during their
lifetime and passed
them on to offspring
•Lamark was wrong!!
•Ex. Giraffes
DARWIN
•British
•Natural Selection:
members of a species
that are best suited to
environment will
survive and reproduce
•4 principles to support
Ex: Galapagos Isles Finch beaks
Darwin’s 4 Principles of Evolution
p 20
Overproduction
Darwin’s 4 Principles of Evolution
Overproduction
When plant or animal
reproduces, it makes more
offspring than actually
survive and reproduce
Ex
Overproduction
Variation
Overproduction
Variation
•There are naturally
occurring variations (differences)
in traits due to different
genetic material or due
to mutations
•Variations get passed on
to offspring
Overproduction
Variation
•There are naturally
occurring variations (differences)
in traits due to different
genetic material or due
to mutations
•Variations get passed on
to offspring
Ex
Flow Map
shows order of events
Overproduction
Variation
Adaptation
Darwin’s 4 Principles of Evolution
Overproduction
Variation
Adaptation
• Inherited trait that
gives an organism an
advantage in its
environment over
other members of the
species
Ex
Darwin’s 4 Principles of Evolution
Overproduction
Variation
Adaptation
Selection
•Organisms with
an adaptation will
survive to
reproduce and
pass on the
adaptation
“Survival of the Fittest”
Ex
For each principle of natural
selection:
• Where did you see that principle modeled in
the activity. Write it down in the example
section in your notes