Download Spring Final Review PP

FINAL SPRING REVIEW
What is an investigative question?

Lisa wants to do an
experiment on a hair product
she’s seen advertised all over
television. Rogooti claims to
increase the speed of hair
growth.

What should Lisa’s investigative
question be?

Does Rogooti speed up hair
growth?
What is a hypothesis?

Lisa’s investigative question
is “Does Rogooti speed up
hair growth?” What would
her hypothesis be?

If a person uses Rogooti,
then their hair will grow
faster.

All hypotheses are in the “If,
then” format.
How do you test a hypothesis?

How should Lisa test her
hypothesis?


She can apply Rogooti to some
members of her family (Marge and
Homer) and measure the growth of
their hair after a month.
How does she know that Rogooti
increased the growth of their hair?

She can measure the hair growth of
Marge and Homer for a month
without Rogooti and compare it to the
growth of their hair with Rogooti.
What are experimental variables?

In Lisa’s experiment what is the:

Independent variable?

Applying the Rogooti to Marge and
Homer’s hair.


Dependent variable?

The amount the hair has grown.


Remember, the independent variable is
what the scientist manipulates!
The dependent variable is what the
scientist measures!
Control?

The measurement of hair growth
WITHOUT Rogooti.

The control is something you can
COMPARE the results to.
How do you interpret a data table?

Lisa recorded her results in this table.

What should her conclusion be?

Her conclusion should be that Rigooti works!
How do you graph information?
Growth in cm
Lisa’s Rigooti Experiment
7
6
5
4
3
2
1
0
Marge wk 1
Homer wk 1
Marge wk 2
Homer wk 2
Week 1

Week 2
Week 3
Week 4
How should Lisa graph her information?


The independent variable is on the X-axis
The dependent variable is on the Y-axis

You can compare the control AND the variables by doing a multi-line
graph!
How do you confirm experimental data?

To confirm the results of her experiment, Lisa should…


Do the experiment again
Have more test subjects
How do you TRANSCRIBE DNA?

Here is a string of DNA:



DNA = C
mRNA = G
C T A
G A U
C
G
G
C
G
C
G A T T C
C U A A G
To TRANSCRIBE the DNA, you have to make it into
mRNA.



Adenine pairs with Uracil
Guanine pairs with Cytosine
Thymine pairs with Adenine

This process takes place in the NUCLEUS!

The DNA strand is too large to leave the nucleus, but the mRNA strand
can.
How do you TRANSLATE DNA?

Now you have your new mRNA strand!

G G A U G C C C U A A G


It is smaller than the DNA strand, and can leave the nucleus for the
cytoplasm.
Once in the cytoplasm, it hooks up with a ribosome, that
“reads” the mRNA strand three nucleotides at a time (a
codon) with the help of tRNA.

This process is TRANSLATION.
How do you TRANSLATE DNA?
peptide bond
ribosome
aa1
aa3
aa2
3-tRNA
1-tRNA
Anti-codon
hydrogen
bonds
U A C
A U G
codon
2-tRNA
G A A
G A U
C U A C U U C G A
mRNA
How do you TRANSLATE DNA?

Every three nucleotides on the mRNA
is a codon.

Every codon has an anti-codon that carries
an amino acid!


As tRNA brings its anti-codons (and amino
acids) to the mRNA strand, it builds
PROTEINS!
We know which amino acids go with each
codons because there is a universal code.

Our mRNA strand: G G A U G C C C U A A G




Is coding for: GGA = Glycine
UGC= Cysteine
CCU= Proline
AAG= Lysine
Where does transcription and translation take
place?

REMEMBER:

TRANSCRIPTION is in the NUCLEUS!

TRANSLATION is in the CYTOPLASM!
What is the genotypic and phenotypic ratio?


A loving couple wants to have children.
They are both heterozygous for brown
eyes. They want a blue-eyed child. What
are their chances?
Genotype


Gene combination for a trait (Bb, BB, bb)
Phenotype

The physical feature resulting from the trait.
(brown eyes or blue eyes)


Mom has the genotype Bb.
Dad has the genotype Bb.
What is the genotypic and phenotypic ratio?
Mom has genotype: Bb
Dad has genotype: Bb


B
b
B
BB
Bb
b
Bb
bb
The genotypic ratio is 1:2:1 or BB : Bb,Bb : bb
The phenotypic ratio is 3:1 or brown, brown, brown : blue
What conditions promote the inheritance of
genetic traits?

Fitness

Fitness is a measure of the
ability to survive and
produce more offspring
relative to other members
of the population in a given
environment.

After the climate change,
jaguars that had larger teeth
and jaws had a higher fitness
than other jaguars in the
populations.
Jaguar Fossil
Modern Jaguar Skull
What is the difference between incomplete
and codominance?
Parents:
MOM
DAD
Incomplete Dominance


The offspring will have a
phenotype somewhat in between
the phenotypes of the two
parents.
Co-Dominance

Both alleles are expressed in the
offspring.
What evidence supports evolution?

Fossils


Embryology


Similar features in the embryos of
different organisms suggests evolution
from a distant common ancestor.
Comparative Anatomy


Fossils show changes in organisms
through time.
Pig
Dolphin
Homologous, analogous, and vestigial
structures give a peek in to the
history of changes that have occurred
in organisms.
DNA

DNA studies show entire gene
sequences in common between
organisms.
Human
What is comparative anatomy?

Homologous structures


Analogous structures


Features that have SIMILAR
STRUCTURES but
DIFFERENT FUNCTIONS
Features that have the
SAME FUNCTION but
DIFFERENT STRUCTURES
Vestigial structures

Remnants of structures that
ONCE HAD A FUNCTION
but NO LONGER DO
What are patterns in the fossil record?

Punctuated Equilibrium


Bursts of evolutionary
activity are followed by
long periods of stability.
Adaptive Radiation


Frilled Sharks
have been
around for
millions of years.
The diversification of one
ancestral species into many
descendent species.
Anolis lizards have
undergone adaptive
radiation on the
Caribbean Islands.
Extinction

Extinctions often occur
when a species as a whole
is unable to adapt to a
change in its environment.
The last Golden Toad
was seen in 1989. It is
thought that a
combination of global
warming and pollution
lead to its extinction.
How do genetics support the idea of
evolution?

The basic definition of
evolution is a change in
the gene pool of a
population of organisms
over time.



All of evolution is based on
genetic change.
Genetic similarities between
two organisms point to a
common ancestor.
By following mutation rates,
scientists can guestimate
how far back two species
diverged from a common
ancestor.
Bonobo
Chimpanzee
By looking at the accumulated mutations in the DNA of
Bonobos and Chimpanzees, scientists have determined
that these two species separated from a common ancestor
less than one million years ago.
What is natural selection?

Natural selection is a
mechanism by which
individuals that have
inherited beneficial
adaptations produce more
offspring on average than
do other individuals.

In nature, the environment
is the selective agent.

Therefore, characteristics are
selected only if they give
advantages to individuals in
the environment.
What are the causes and effects of natural
selection?

There are four main principles to the
theory of natural selection:

Variation


Overproduction


Organisms have more offspring than can
survive.
Adaptation


Heritable differences, or variations, exist in
every population
Sometimes, a certain variation allows an
individual to survive better than other
individuals it competes against in its
environment.
Descent with Modification

More individuals will have the variation in
every following generation.
What are the causes and effects of
natural selection?

Descent With
Modification

Over time, natural selection
will result in species with
adaptations that are well
suited for survival and
reproduction in an
environment.

More individuals will have the
trait in every following
generation, as long as the
environmental conditions
continue to remain beneficial
for that trait.
How do new species emerge?

Isolating Mechanisms


Reproductive Isolation


Occurs when two populations are capable of
interbreeding but have differences in courtship rituals
or other reproductive strategies.
Geographic Isolation


Reproductive isolation occurs when members of
different populations can no longer successfully mate
with one another.
Behavioral Isolation


To make new species, the gene pools of the
populations must become separated.
Two populations are separated by a geographic
barriers such as rivers, mountains, or bodies of water.
Temporal Isolation

Two or more species reproduce at different times.
What are the characteristics of species?

A species is a group of
organisms that breed with one
another and produce fertile
offspring.
Chinstrap Penguin
Emperor Penguin
Macaroni Penguin
What are allele frequencies?

Genetic variation is stored in a population’s gene pool—the
combined alleles of all the individuals in a population.


Different combinations of alleles in a gene pool can be formed when
organisms mate and have offspring.
Each allele exists at a certain rate, or frequency.

An allele frequency is a measure of how common a certain allele is in the
population.
How do allele frequencies change?

Mutation


Recombination


A mutation is a random
change in the DNA of a
gene.
Most recombination
occurs during meiosis—
through crossing over.
Hybridization

The crossing of two
different species that
share common genes.
How do you graph allele frequencies?

Normal Distribution


Directional Selection


When natural selection favors
phenotypes at one extreme of a
trait’s range.
Normal
Directional
Stabilizing Selection


Most traits will fall under normal
distribution (bell curve)
When natural selection favors
phenotypes in the middle range.
Disruptive Selection

When natural selection favors both
extreme phenotypes, while
individuals with intermediate
phenotypes are selected against.
Stabilizing
Disruptive
How do humans influence allele
frequency?

Genetic Drift

Genetic drift causes the LOSS of
genetic diversity in a population.

Founder Effect

The founder effect happens after a
small number of individuals colonize
a new area.

Bottleneck Effect

The bottleneck effect happens
when an event greatly reduces the
size of the population.
How does the environment influence
allele frequency?

Industrial Melanism

Refers to the genetic darkening of species in response to pollutants.

Originally, the vast majority of peppered moths had light coloration, which effectively
camouflaged them against the light-colored trees and lichens upon which they rested.

Widespread pollution during the Industrial Revolution in England, many of the lichens
died out, and the trees which peppered moths rested on became blackened by soot,
causing most of the light-colored moths to die off due to predation.
 At the same time, the dark-colored moths flourished because of their ability to
hide on the darkened trees.

Since then, with improved environmental standards, light-colored peppered moths
have again become common.
How does immigration affect allele
frequency?

Gene Flow


The movement of alleles from one
population to another is called gene flow.
For many animals, gene flow occurs when
individuals move between populations.
 For example: Certain birds leave their
nesting areas once they are able to fly.


These birds most likely join new
populations.
The alleles that these birds have then
become a part of another population’s
gene pool.
 Gene flow increases the genetic
variation of the receiving population.
What is the difference between biotic and
abiotic factors?

Biotic


Factors that are living
things, such as plants,
animals, fungi, and bacteria.
Abiotic

Factors that are non-living
things such as moisture,
temperature, wind, sunlight,
and soil. The balance of
these factors determines
which living things can
survive in a particular
environment.
What influences do biotic and abiotic factors
have on populations?


Density-Dependent Limiting Factors
A limiting factor that depends on
population size.

Usually includes biotic factors





Competition
Predation
Parasitism
Disease
Density-Independent Limiting
Factors

Affect all populations in similar ways,
regardless of the population size.

Usually includes abiotic factors


Fire
Drought
What are some differences and similarities
between heterotrophs and autotrophs?

Autotrophs
Also known as producers
 Organisms that get their
energy from non-living
resources, meaning—they
make their own food.


Heterotrophs

Also known as consumers

Organisms that get their
energy by eating other living
or once-living resources, such
as plants and animals.
How do you interpret a food chain?

A food chain is a
sequence that links
species by their feeding
relationships.

This model chain only
shows the connection
between ONE producer
and a SINGLE chain of
consumers within an
ecosystem.

Energy flows from
PRODUCER TO
CONSUMER
Compare a food chain and an energy
pyramid.

An energy pyramid is a diagram that compares the energy used by
producers, primary consumers, and other trophic levels.


As energy moves up the food chain—IT DECREASES
Those organisms at the top of the food chain, have the lease amount of
energy.
How do biomass levels change through food
webs and energy pyramids?
 Biomass


pyramid
Diagram that compares the
biomass of different trophic
levels within an ecosystem.
It provides a picture of the
mass of producers needed
to support primary
consumers, the mass of
primary consumers needed
to support secondary
consumers, and so on.

As you go UP the food chain
biomass DECREASES
5,000 Hawks
50,000 snakes
500,000 bunnies
5,000,000 blades
of grass
How does immigration and emmigration affect
population size?

Immigration



The movement of
individuals into an area.
Causes population
growth.
Emigration


The movement of
individuals out of an area.
Causes population
decline.
What is carrying capacity?

Carrying Capacity (K)


The environment can only
support so many
individuals.
The number that
represents the largest
amount of individuals an
environment can support at
any one time is the carrying
capacity.

Once populations reach
carrying capacity, they
undergo logistic growth.
What are chemical cycles?

A biogeochemical cycle
is the movement of a
particular chemical
through the biological
and geological, or living
and non-living, parts of
an ecosystem.

They include the carbon,
nitrogen, phosphorous,
water, and oxygen cycles!
How do humans affect the
environment?

Air quality


Smog is a type of air pollution
caused by the interaction of
sunlight with pollutants produced
by fossil fuel emissions.
Water quality


Acid rain is a type of precipitation
produced when pollutants in the
water cycle cause rain pH to drop
below normal levels.
Chemical contaminants, raw
sewage, trash, and other waste
products are only a few pollutants
that make their way into rivers,
lakes, and aquifers all over the
world.
How do humans influence biodiversity?

Biodiversity


Loss of Habitat


The wide array and assortment of
species that are found in any
ecosystem.
The loss of habitat can put species
in danger of becoming extinct.
Habitat Fragmentation

Habitat fragmentation occurs
when a barrier forms that prevents
an organism from accessing its
entire home range.

Often, habitat fragmentation is
caused by the building of roadways
or the harvesting of forests.
How do humans impact natural
systems?

Urban sprawl

As cities grew larger, people
moved into suburbs—urban
sprawl.


Suburban growth consumes
farmland and natural habitats.
Global Warming

The trend of increasing temperatures
is known as global warming.
 Sea level rise, global temperature
rise, warming oceans, shrinking ice
sheets, declining arctic sea ice,
glacial retreat, ocean acidification,
and an increase in extreme
weather events are all
consequences of global warming.
How do humans use renewable
resources?

Resources that cannot be used up
or can replenish themselves over
time are called renewable
resources.


Wind and solar energy are
renewable resources because they
cannot be used up by humans.
Other resources, such as those that
come from plants and animals, can
be used up, but because they could
last indefinitely through re-growth
and reproduction, they are
renewable.
What are invasive species?

An introduced species is any
organism that was brought into
an ecosystem as the result of
human activities.
 Introduced species can pose
a great threat to the stability
of an ecosystem if they prey
on or crowd out native
species.
Burmese pythons are an introduced species
in the Florida Everglades. It feeds on small
animals, such as rats, birds, raccoons, and
even dogs. The same organisms that
alligators feed on. Competition between the
introduced and native species is fierce.
What are some conservation
techniques?

Sustainable Practices


Reforestation


Timber companies cut selected trees rather than clear
cutting forests. This encourages rapid re-growth of trees,
and has a minimal impact on the ecosystem.
Fishing Regulation


Sustainable development is a practice in which natural
resources are used and managed in a way that meets
current needs without hurting future generations.
Rotation, gear review, harvest reduction, and fishing bans
are all enforced to help fish populations replenish.
Conservation

Conservation practices focus on a few species but
benefit entire ecosystems.

The listed species is often called an umbrella species because its
protection means a wide range of other species will also be
protected.