ogt cram session 2. structure of ecosystems/levels of organization organism – individual living...

OGT Cram OGT Cram Session 2Session 2

Structure of Structure of Ecosystems/Levels of Ecosystems/Levels of

OrganizationOrganization Organism – Organism – individual living (biotic) thingindividual living (biotic) thing Population – Population – group of organisms, all of one group of organisms, all of one

species, which live in the same place and species, which live in the same place and the same timethe same time

Community – Community – all the populations of all the populations of different species, same place, same timedifferent species, same place, same time

Ecosystem – Ecosystem – Populations of plant and Populations of plant and animals that interact with each other in a animals that interact with each other in a given area and with the abiotic parts (non-given area and with the abiotic parts (non-living)living)

Biosphere – Biosphere – The portion of Earth that The portion of Earth that supports lifesupports life

Levels of Organization Levels of Organization (cont.)(cont.)

I. EcosystemsI. Ecosystems

BiomesBiomes

A. TundraA. Tundra Extremely cold climate (-34 degrees C to 12 Extremely cold climate (-34 degrees C to 12

degrees C)degrees C) Low biotic diversity Low biotic diversity Simple vegetation structure Simple vegetation structure Limitation of drainage Limitation of drainage

Short season of growth and reproductionShort season of growth and reproduction

This fact has been on 3 OGT tests!

B. Marine B. Marine Cover ¾ the planetCover ¾ the planet 1. Oceans1. Oceans

Largest of all Largest of all ecosystemsecosystems

2. Coral Reefs2. Coral Reefs Very diverseVery diverse Coral is dominant Coral is dominant

organismorganism Ex. Great Barrier ReefEx. Great Barrier Reef

EstuariesEstuaries Where freshwater Where freshwater

rivers meet the rivers meet the ocean.ocean.

Fertile soil produces Fertile soil produces diversitydiversity

C. Freshwater BiomesC. Freshwater Biomes 1. Ponds, Lakes, Streams1. Ponds, Lakes, Streams

D. Taiga D. Taiga Stretches across Canada, Northern Stretches across Canada, Northern

Europe and AsiaEurope and Asia Soil is acidic and has few nutrientsSoil is acidic and has few nutrients The abundance of evergreen trees The abundance of evergreen trees

provide shelter for many large animalsprovide shelter for many large animals Lynx, elk, caribou, wolvesLynx, elk, caribou, wolves

E. DesertE. Desert Hot daysHot days Cold nightsCold nights Little precipitationLittle precipitation Low biodiversityLow biodiversity

F. RainforestF. Rainforest Hot temps Hot temps High precipitationHigh precipitation High diversityHigh diversity Contain species not Contain species not

yet discoveredyet discovered Being destroyed by Being destroyed by

deforestationdeforestation Kills animalsKills animals Reduces amount of Reduces amount of

oxygenoxygen

G. Deciduous Forest/Temperate G. Deciduous Forest/Temperate 70-150 cm of rainfall70-150 cm of rainfall Deciduous treesDeciduous trees

Leaves turn color in fallLeaves turn color in fall Leaves fall off in winterLeaves fall off in winter

Squirrels, mice, bearsSquirrels, mice, bears

Biome LocationsBiome Locations

SuccessionSuccession

Primary SuccessionPrimary Succession When organisms colonize barren land (rock)When organisms colonize barren land (rock)

Pioneer species – lichen break down rockPioneer species – lichen break down rock Small ferns, fungi, and insects appear after lichen dieSmall ferns, fungi, and insects appear after lichen die

Secondary Succession Secondary Succession Areas that previously contain lifeAreas that previously contain life Soil already existsSoil already exists

Example: after a fire has burned a forestExample: after a fire has burned a forest

Climax Community Climax Community Stable mature community Stable mature community

1.1. Density-Density-dependent factorsdependent factors

DiseaseDisease CompetitionCompetition ParasitesParasites Food availabilityFood availabilityLarger and closer a Larger and closer a

group is the group is the greater the effect. greater the effect.

Density-independent Density-independent factorsfactors

Most are abioticMost are abiotic TemperatureTemperature Disasters: floods, Disasters: floods,

storms, drought, storms, drought, pollutionpollution

Check this out…….(turn on Check this out…….(turn on volume)volume)

http://www.geowords.org/ensci/imagesbook/04_03_succession.swf

Food Webs/Food ChainsFood Webs/Food Chains

Food webs show what all organisms eat.Food webs show what all organisms eat.

a. Increase in the owl a. Increase in the owl populationpopulation

A. The mouse population A. The mouse population has increasedhas increased

Food Webs/Food ChainsFood Webs/Food Chains

Food Chain is a straight line and only Food Chain is a straight line and only show 1 possible path of the food webshow 1 possible path of the food web

Food Web/Chain Key Food Web/Chain Key PointsPoints

If you get rid of an animal from the food If you get rid of an animal from the food web/food chain, the animal that eats the web/food chain, the animal that eats the lost animal will decline in numbers.lost animal will decline in numbers.

If you introduce an animal/organism to the If you introduce an animal/organism to the food chain all animals who eat the new food chain all animals who eat the new animal/organism will increase in numbers.animal/organism will increase in numbers.

If you introduce a species that eats the If you introduce a species that eats the same organisms as another already in the same organisms as another already in the food chain, then the animal already in the food chain, then the animal already in the food chain will decline in numbers. (The food chain will decline in numbers. (The visa versa is also true.)visa versa is also true.)

Animal RelationshipsAnimal Relationships Mutualism = Both animals benefitMutualism = Both animals benefit Commensalisms = One animal benefits, Commensalisms = One animal benefits,

the other is not harmed.the other is not harmed. Parasitism = One animal benefits, the Parasitism = One animal benefits, the

other is harmed!other is harmed! Carnivore = eats meatCarnivore = eats meat Herbivore = eats plantsHerbivore = eats plants Omnivore = eats bothOmnivore = eats both Producers = make their own food (green)Producers = make their own food (green) Consumer = eat producersConsumer = eat producers

Mutualism = both Mutualism = both organisms benefitorganisms benefit

Yellow-billed oxpeckers feed on ecto-Yellow-billed oxpeckers feed on ecto-parasites on the hide of a grazing parasites on the hide of a grazing bull hippopotamus. bull hippopotamus.

ParasitismParasitism

A parasite feeds on A parasite feeds on a host. Usually the a host. Usually the parasite does not parasite does not kill the host (not kill the host (not immediately)immediately)

Ex) ticsEx) tics (endoparasites-(endoparasites-

inside the host)inside the host)

Energy PyramidEnergy Pyramid

CommensalismCommensalism

One-sided One-sided relationship. One relationship. One species benefits species benefits with out harming with out harming the other speciesthe other species

CompetitionCompetition

When 2 or more species share When 2 or more species share similar characteristics and require similar characteristics and require the same resources they compete.the same resources they compete.

Alien species- non-native species, Alien species- non-native species, reproduce out of control because reproduce out of control because they have no natural predatorsthey have no natural predators

Carrying CapacityCarrying Capacity

The population of a species that an The population of a species that an area will generally supportarea will generally support

Usually there is Usually there is equilibriumequilibrium-a -a balance among speciesbalance among species

AutotrophsAutotrophs

““Automatically” make their own foodAutomatically” make their own food ProducersProducers Plants-that can make their own food Plants-that can make their own food

by photosynthesisby photosynthesis

HeterotrophsHeterotrophs

Cannot make their own food.Cannot make their own food. Animals must obtain foodAnimals must obtain food

Herbivores-plantsHerbivores-plants Carnivores-meatCarnivores-meat Omnivores-BothOmnivores-Both

Environmental ProblemsEnvironmental Problems

Pollution-rise of industry has led to Pollution-rise of industry has led to increased air and water pollutionincreased air and water pollution

Ozone LayerOzone Layer

Ozone absorbs the suns UV raysOzone absorbs the suns UV rays Without ozone, the UV rays would Without ozone, the UV rays would

lead to genetic mutations in all living lead to genetic mutations in all living cellscells

CFC’s break down the ozone layerCFC’s break down the ozone layer

PesticidesPesticides

Poisonous chemicals to help control Poisonous chemicals to help control insects, but they become part of the insects, but they become part of the water and soil harming other living water and soil harming other living thingsthings

Acid RainAcid Rain

Pollutants in the atmosphere get Pollutants in the atmosphere get washed out of the air when it rainswashed out of the air when it rains

These pollutants endanger the These pollutants endanger the environmentenvironment

Here’s What they (OGT) has Here’s What they (OGT) has asked in the last 4 asked in the last 4

years………years………

Cell TheoryCell Theory

1. All organisms are 1. All organisms are composed of one or more composed of one or more cellscells

2. The cell is the basic unit of 2. The cell is the basic unit of organization of organismsorganization of organisms

3.All cells come from 3.All cells come from preexisting cellspreexisting cells

ProkaryoteProkaryote

1. Prokaryotes: No membrane 1. Prokaryotes: No membrane bound organelles (especially bound organelles (especially nucleus)nucleus)a. Bacteria (Kingdom Monera)a. Bacteria (Kingdom Monera)b. DNA is just “floating” around b. DNA is just “floating” around

along with ribosomesalong with ribosomesc. Mostly unicellular organismsc. Mostly unicellular organisms

EukaryoteEukaryote

1. Eukaryotic: cells containing 1. Eukaryotic: cells containing membrane-bound organellesmembrane-bound organelles a. mostly multicellulara. mostly multicellular b. some unicellular (algae, yeast)b. some unicellular (algae, yeast) C. have organelles: structures C. have organelles: structures

with special functions in the cellwith special functions in the cell D. Nucleus: largest in animal cellsD. Nucleus: largest in animal cells

Has Nucleus No Nuclear

Membrane

Ribosomes

and DNA

Cell StructureCell Structure

Cell StructuresCell Structures

1. Cell wall: rigid layer of 1. Cell wall: rigid layer of nonliving material that nonliving material that surrounds the cells of plantssurrounds the cells of plantsMade of celluloseMade of celluloseProtects and supports the cellsProtects and supports the cells

2. Cell membrane: Boundary 2. Cell membrane: Boundary that protects the cell from that protects the cell from the environment & controls the environment & controls what comes in and outwhat comes in and outAll cells haveAll cells haveLike a screen doorLike a screen door

3. Nucleus: control center for 3. Nucleus: control center for the cellthe cell

4. Ribosomes: grain like 4. Ribosomes: grain like bodies on the ER & in the bodies on the ER & in the

cytoplasmcytoplasm

5.Endoplasmic Reticulum: (called 5.Endoplasmic Reticulum: (called ER) carry proteins and materials ER) carry proteins and materials

within the cellwithin the cell

6. Golgi Body: receives and 6. Golgi Body: receives and packages proteins from ER and packages proteins from ER and

distributes around cell and distributes around cell and body (mailroom)body (mailroom)

7. Cytoplasm: clear gelatinous 7. Cytoplasm: clear gelatinous fluid inside a cellfluid inside a cell

8. Vacuoles: storage area of the 8. Vacuoles: storage area of the cellcell

Plant has one large vacuolePlant has one large vacuoleStores food, waste, & enzymesStores food, waste, & enzymes

9. Mitochondria = powerhouse of the 9. Mitochondria = powerhouse of the cell; where cell energy comes from.cell; where cell energy comes from.

10. Chloroplasts: ONLY IN 10. Chloroplasts: ONLY IN PLANTS captures sunlight and PLANTS captures sunlight and

produces food for the cellproduces food for the cell

11. Flagella = used for 11. Flagella = used for movementmovement

12. Cilia = used for 12. Cilia = used for movement; tiny hair-like movement; tiny hair-like structures; found on cells structures; found on cells that need to move mucusthat need to move mucus

D. Absence of a nuclear D. Absence of a nuclear membranemembrane

B. Viruses require a host B. Viruses require a host cell to reproduce.cell to reproduce.

C. flagellumC. flagellum

B. flagellaB. flagella

Questions they (OGT) has Questions they (OGT) has asked the last 4 years.asked the last 4 years.

D. Place the rabbit in a D. Place the rabbit in a cage with a heated floor.cage with a heated floor.

B.B. D.

EvolutionEvolution

Charles Darwin (1809-1882)Charles Darwin (1809-1882)

1.1. Natural SelectionNatural Selectiona.a. ““Only the strongest survive”Only the strongest survive”

2.2. Darwin hypothesized that when Darwin hypothesized that when animals had traits that helped them animals had traits that helped them live, they would pass them on to live, they would pass them on to their offspring.their offspring.

3.3. Animals who did not possess these Animals who did not possess these traits died.traits died.

Darwin’s ExampleDarwin’s Example

1.1. Darwin noted the different beak Darwin noted the different beak structures of finches depended on structures of finches depended on the island they came from.the island they came from.

2.2. Finches who lived on islands Finches who lived on islands plentiful in nuts and berries had plentiful in nuts and berries had different beaks than finches who different beaks than finches who lived on islands plentiful in insects.lived on islands plentiful in insects.

Even though all these birds are finches they developed different beaks depending on the plentiful food source of specific islands.

Examples of Natural Examples of Natural SelectionSelection

1.1. Galapagos IguanasGalapagos Iguanasa.a. Some iguanas have Some iguanas have

evolved to eat algae.evolved to eat algae.b.b. Some iguanas have Some iguanas have

developed large claws to developed large claws to help them cling to rock.help them cling to rock.

c.c. These iguanas evolved These iguanas evolved from other iguanas from other iguanas because they need because they need those two traits to those two traits to survive.survive.

d.d. The algae eating, long The algae eating, long clawed iguanas passed clawed iguanas passed these trait on to their these trait on to their young.young.

e.e. Iguanas not having that Iguanas not having that trait.trait.

Everyday green iguana

Galapagos marine iguana

Other adaptationsOther adaptations

1.1. CamaflougeCamaflougea. Enables species to a. Enables species to

blend in with their blend in with their surroundings.surroundings.

Can you find the snake’s head?

2. Mimicry – enables 2. Mimicry – enables a species to look a species to look like other specieslike other species

What part of the plant is this?It’s not part of the plant at all, it’s an insect.

Darwin HypotheticalDarwin Hypothetical1.1. Let’s say there was a new “killer” virus that affected Let’s say there was a new “killer” virus that affected

dogs.dogs.2.2. This flu bug only affected dogs with long hair. So, if a dog This flu bug only affected dogs with long hair. So, if a dog

had long hair (more than ¾ inch long) it would get the had long hair (more than ¾ inch long) it would get the virus and die.virus and die.

3.3. In 20 years, will all dogs have long or short hair? WHY?In 20 years, will all dogs have long or short hair? WHY?

All dogs would have short hair because all the long hair All dogs would have short hair because all the long hair dogs have died from the virus. There would only be short dogs have died from the virus. There would only be short haired dogs mating with short hair dogs. haired dogs mating with short hair dogs.

You could say all dogs with short hair were “naturally You could say all dogs with short hair were “naturally selected” to live. The dog species has evolved from selected” to live. The dog species has evolved from having both short and long hair to having only short hair.having both short and long hair to having only short hair.

1.1. Populations evolve not individuals.Populations evolve not individuals.

B. B.

C. Had a higher survival C. Had a higher survival rate than light moths in the rate than light moths in the

same areasame area

One last thing the OGT One last thing the OGT might get you on……might get you on……

Jean Baptiste Lamarck (1744-1821)Jean Baptiste Lamarck (1744-1821) Came before DarwinCame before Darwin Had some of the same ideas as Darwin Had some of the same ideas as Darwin No one ever believed him.No one ever believed him. Died in obscurity and poverty.Died in obscurity and poverty.

GeneticsGenetics

1. The dominant trait will always be visible1. The dominant trait will always be visible

2. Dominant-always masks the recessive; 2. Dominant-always masks the recessive; represented by uppercase letter (T, H, D, represented by uppercase letter (T, H, D, R)R)

3.3. Recessive-will be masked by dominant; Recessive-will be masked by dominant; represented by lowercase letter (t, h, d, represented by lowercase letter (t, h, d, r)r)

-For a recessive trait to be visible, there -For a recessive trait to be visible, there must be two (tt, hh, dd, rr)must be two (tt, hh, dd, rr)

DDDD

dddd

DdDd

Punnet SquaresPunnet Squares

Cross a homozygous dominant with Cross a homozygous dominant with a homozygous recessive.a homozygous recessive.

HH x hh

H

H

h h

H

H

hh

Hh

Hh Hh

Hh

hh

H

H

OGT TricksOGT Tricks

Sometimes they give you a recessive Sometimes they give you a recessive

allele like this: allele like this: CCcc

CCc c is the same as a “c” is the same as a “c”

A. O%A. O%

D. 100%D. 100%

SEX allelesSEX alleles Males – XYMales – XY Females – XXFemales – XX Recessive diseasesRecessive diseases

Diseases that are recessive on the X Diseases that are recessive on the X chromosomechromosome

INFO:INFO: Sex inherited diseasesSex inherited diseases

Females can not get diseases that appear on Y Females can not get diseases that appear on Y chromosomechromosome

Males are more likely to get a recessive diseaseMales are more likely to get a recessive disease If the recessive allele appears on the X males get If the recessive allele appears on the X males get

diseasedisease Females are less likely to get a recessive diseaseFemales are less likely to get a recessive disease

If recessive allele appears on one X chromosome the If recessive allele appears on one X chromosome the other X chromosome can cover it with a dominant other X chromosome can cover it with a dominant alleleallele

How to Read PedigreesHow to Read PedigreesAffected male

Unaffected female

Unaffected male

Female carrier, She does not have Disease but can pass it on to her kids.

Pedigrees = a chart that shows you Pedigrees = a chart that shows you the family history of passing traitsthe family history of passing traits