FINAL SPRING REVIEW

Aquarium Curiosity In aquarium, you

are curious to see if lowering the pH has an effect on the fish.

What is your hypothesis? If I lower the pH

levels of the aquarium to 4.0, then the fish will die.

Make an experimental procedure for this experiment Remember, it must include both an

experimental group and a control group. 1. Have two identical fish tanks. 2. One fish tank will have water with a

pH of 7.0. 3. One fish tank will have water with a

pH of 4.0. Which tank is the experimental group?

The fish tank with a pH of 4.0. Which tank is the control group?

The fish tank with a pH of 7.0. What are some constants that you can

have? Same number of fish, same amount of water,

the fish receive the same amount of food, same temperature of water, etc.

Observation You look at each tank, and this is what you

see.pH 7.0 Tank

pH 4.0 Tank

Day 1

Day 1

Day 2 Day 3

Day 2 Day 3

Create A Graph Based on your observations, create a

graph.

Num

ber o

f Liv

ing

Fish

What was your dependent variable?What was your independent variable?

Number of living fishpH level

Converting a bar graph to a line graph In Arizona, zombies are a constant problem during the

summer vacation season. To combat zombies, the Arizona Zombiefication Service decided to spray a zombicide called ZZT. This zombicide was used on a population of 100 zombies with 3 genotypes in the Metro Center parking lot.Zombies with genotype bb and Bb

are easily killed by the ZZT, but zombies with genotype BB are not affected.

Draw a line graph that shows how the entire population of zombies in the parking lot would change after spraying of ZZT.

Why would the population increase after a while?

The population that is unaffected by ZZT with the genotype BB, would flourish.

Reading graphs-Zombie Apocolypse Humans can be destructive on the environment and the native

species that live there. In the Spring of 2088, a zombie apocalypse broke out and reduced the human population. With the advent of ZZT, the zombie hoards were reduced. A scientist wanted to know what effects the rebounding human

population would have on wild animal species. He took two sites, and spread ZZT with one site (reducing the zombie population, experimental site), and let the other site flourish with zombies (control site). These are the results.

Interpret Graphs Based on the graph, which site contained

the most wild animal species? The control sites.

What did the spreading of ZZT do to the zombie population in the experimental sites? Reduce the zombie population.

What did the spreading of ZZT do to the human population in the experimental sites? By reducing the zombie population, it

would allow the human population to flourish.

Why would there be more wild animal species in the areas without ZZT? If humans are destructive to the

environment, then by having larger populations they would destroy the habitat of the wild animal species in the experimental sites.

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. Remember, the independent

variable is what the scientist manipulates!

Dependent variable? The amount the hair has grown.

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?

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!

Week 1 Week 2 Week 3 Week 401234567

Marge WithoutHomer WithoutMarge WithHomer With

Lisa’s Rigooti Experiment

Gro

wth

in c

m

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 C T A C G G G A T T C

mRNA = 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.

G G A U G C C C U A A G

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?

mRNAA U G C U A C U U C G

1-tRNA 2-tRNA

U A C G

aa1 aa2

A UAhydrogen

bonds codon

peptide bond

3-tRNA

G A A

aa3

Anti-codon

ribosome

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?

The genotypic ratio is 1:2:1 or BB : Bb,Bb : bb The phenotypic ratio is 3:1 or brown, brown,

brown : blue

B b

B

B

B

b

Mom has genotype:

Dad has genotype:

Bb

Bb

B

b

b

b

B

b

Who is Gregor Mendel? Mendel studied

genetics through the use of math, probability and pea plants.

He found that variation occurs through the inheritance of individual alleles from each parent Dominant alleles mask

recessive alleles (TT- tall, Tt- tall)

Recessive alleles are only expressed when both present (tt- short)

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?

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.

Parents:

MOM DAD

What evidence supports evolution? Fossils

Fossils show changes in organisms through time.

Embryology Similar features in the

embryos of different organisms suggests evolution from a distant common ancestor.

Comparative Anatomy 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.

PigDolphin

Human

What is comparative anatomy? Homologous

structures Features that have

SIMILAR STRUCTURES but DIFFERENT FUNCTIONS

Analogous structures 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 The diversification of

one ancestral species into many descendent species.

Gradualism The idea that

evolution is a slow and steady process.

Frilled Sharks have been around for millions of years.

Anolis lizards have undergone adaptive radiation on the Caribbean Islands.

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.

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.

Bonobo Chimpanzee

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

Heritable differences, or variations, exist in every population

Overpopulation Organisms have more offspring

than can survive. Adaptation

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

To make new species, the gene pools of the populations must become separated.

Reproductive Isolation Reproductive isolation occurs when

members of different populations can no longer successfully mate with one another.

Behavioral Isolation Occurs when two populations are capable

of interbreeding but have differences in courtship rituals or other reproductive strategies.

Geographic Isolation 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.

Emperor Penguin

Chinstrap Penguin

Macaroni Penguin

What is a species? All of these lizards live

near each other and eat the same types of food. Populations A and B will mate together where their populations come into contact with each other (the overlapping circle) and produce fertile offspring. How many species are

represented by this graph? 6!

Because A and B can breed and produce fertile offspring, they are considered to be a single species.

A

BC

D

E

FG

C

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

A mutation is a random change in the DNA of a gene.

Recombination 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

Most traits will fall under normal distribution (bell curve)

Directional Selection When natural selection

favors phenotypes at one extreme of a trait’s range.

Stabilizing Selection When natural selection

favors phenotypes in the middle of a trait’s range.

Disruptive Selection When natural selection

favors both extreme phenotypes, while individuals with intermediate phenotypes are selected against.

Normal Directional

Stabilizing Disruptive

How do humans influence allele frequency? Genetic Drift

Genetic drift causes the LOSS of genetic diversity in a population.

Bottleneck Effect The bottleneck effect

happens when an event greatly reduces the size of the population.

Founder Effect The founder effect happens

after a small number of individuals colonize a new area.

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 the environment influence allele frequency? Peppered coloration (PP

and Pp) is dominant to black coloration (pp) in moths. Which moth phenotype would

have an increased fitness after the industrial revolution? Soot blackening the trees

caused 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. Fitness is the ability to

outbreed your competitors!

P pP PP Ppp Pp pp

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.

Who is Charles Darwin? Darwin is a naturalist who

studied variations in organisms, geology and fossils. He wrote a book called On the

Origin of Species that explained how natural selection occurs.

He thought that traits were blended and was unaware of Mendel’s studies on how heritable characteristics are inherited distinctly from each parent which led to variation in offspring.

Darwin’s idea of natural selection helped to explain that traits will be passed to future generations and increase variation in members of a 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.

Food Webs Show complex food relationships in

ecosystems. Arrows show the movement of energy through the

food web. Pick out a single food chain in this web.

Fungi to squirrel to hawk!

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

5,000,0000 blades of grass

500,000 bunnies

5,000 snakes

5 Hawks

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 maximum

number of individuals that an environment can support Logistic growth is

growth limited by resources. Happens when an area has reached its carrying capacity.

Exponential growth – occurs with abundant amounts of resources

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!

The Nitrogen Cycle The nitrogen cycle

relies heavily on bacteria who take atmospheric nitrogen and convert it to useable forms (nitrogen fixation) as well as helping decompose nitrogen and return it back to the atmosphere and soil (denitrification).

The Carbon Cycle Carbon comes in

many forms, and is essential for life. Photosynthesis plays a

huge role in the carbon cycle by scrubbing carbon dioxide from the atmosphere.

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

The wide array and assortment of species that are found in any ecosystem.

Loss of Habitat 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.

What are invasive species? An introduces species is

any organism that was brought into an ecosystem as the result of human activities. Introduces 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.

Greenhouse Effect Define: excessive CO2

in the atmosphere Causes:

Increased use of fossil fuels (coal, oil), non-renewable resources (another way to say fossil fuels), clear cutting (cutting of trees from a forest)

What can we do? Increased use of

renewable, clean energy sources such as solar and wind energy.

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 some conservation techniques? Sustainable Practices

Sustainable development is a practice in which natural resources are used and managed in a way that meets current needs without hurting future generations.

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 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.