Living Environment Lab Review

Living EnvironmentLiving Environment

Part D (Required Labs)Part D (Required Labs)

ReviewReview

Beaks of FinchesBeaks of Finches

14 Species of Darwin’s finches14 Species of Darwin’s finches– Beaks vary in size and shapeBeaks vary in size and shape– Bodies vary in size and shapeBodies vary in size and shape


Different beak sizes and shapes differ Different beak sizes and shapes differ in their efficiency at performing in their efficiency at performing particular tasks.particular tasks.


Why do offspring of better-adapted Why do offspring of better-adapted individuals inherit many of their individuals inherit many of their parents’ favorable variations?parents’ favorable variations?


Why do offspring of better-adapted Why do offspring of better-adapted individuals inherit many of their individuals inherit many of their parents’ favorable variations?parents’ favorable variations?

– Favorable variations allow parents Favorable variations allow parents to survive and then reproduce to survive and then reproduce more. Their offspring then may more. Their offspring then may possess those variations. possess those variations.


What are the parts of Darwin’s What are the parts of Darwin’s theory of Natural Selection?theory of Natural Selection?


What are the parts of Darwin’s theory of What are the parts of Darwin’s theory of Natural Selection?Natural Selection?

– OVCSROVCSROnly (Overproduction)Only (Overproduction)Vince (Variation)Vince (Variation)Can (Competition)Can (Competition)Suck (Survival of the Fittest)Suck (Survival of the Fittest)Rutabegas (Reproduction)Rutabegas (Reproduction)


Variation means ______________. Variation means ______________.

Why do the finches of the Galapagos Why do the finches of the Galapagos Islands show so much variation?Islands show so much variation?


Variation means Variation means __differencesdifferences______. .

Why do the finches of the Galapagos Why do the finches of the Galapagos Islands show so much variation?Islands show so much variation?

– Each finch species adapted to their Each finch species adapted to their different environments. different environments.


What did the tools represent?What did the tools represent?


What did the tools represent?What did the tools represent?– The different beak shapes. The different beak shapes.


What did the different seeds What did the different seeds represent? represent?


What did the different seeds What did the different seeds represent? represent?

The different types of food available on The different types of food available on the island.the island.


Why are the 4 trials completed and Why are the 4 trials completed and then averaged for each of the then averaged for each of the “feedings”? “feedings”?


Why are the 4 trials completed and Why are the 4 trials completed and then averaged for each of the then averaged for each of the “feedings”? “feedings”?

The data is more The data is more accurate when the trials accurate when the trials are averaged.are averaged.


All of the finches have similarities. All of the finches have similarities. Why is this the case? Why is this the case?


All of the finches have similarities. All of the finches have similarities. Why is this the case? Why is this the case?

– All of the finches share a common All of the finches share a common ancestor.ancestor.

Relationships and BiodiversityRelationships and Biodiversity

Botana curus (fictional plant for lab Botana curus (fictional plant for lab purposes) produces Curol. purposes) produces Curol.

– This was supposedly used to This was supposedly used to ________________. ________________.


Botana curus Botana curus (fictional plant for lab (fictional plant for lab purposes) produces Curol. purposes) produces Curol.

– This was supposedly used to This was supposedly used to cure cure cancercancer. .


The plants used in the lab, and what The plants used in the lab, and what they were modeled after… maybe?they were modeled after… maybe?

This is the Pacific Yew. It contains “Taxol” – used to treat cancer.

This is what was used in the lab, though.


Why was it necessary to find an Why was it necessary to find an alternative to alternative to Botana CurusBotana Curus? ?

Story of Story of TaxolTaxol


Why was it necessary to find an Why was it necessary to find an alternative to alternative to Botana CurusBotana Curus? ?

In the lab, the plant was endangered In the lab, the plant was endangered and was in short supply. and was in short supply.

(In reality, the Pacific Yew only (In reality, the Pacific Yew only produces one dose of drug per tree! produces one dose of drug per tree! Scientists wanted to find an Scientists wanted to find an alternative!)alternative!)

http://www.phcog.org/Taxus/Taxus_Web.html


Chromatography:Chromatography:

Sorts molecules based on ____


Chromatography:Chromatography:

Sorts molecules based on SIZE.The smaller molecules move faster up the paper. Larger ones move slower and stay toward the bottom of the paper.


What is an indicator?What is an indicator?


What is an indicator?What is an indicator?

They are used to detect certain They are used to detect certain substances. substances.

In the lab, we used a white powder to In the lab, we used a white powder to test for “Enzyme M”. test for “Enzyme M”.


Gel Electrophoresis: Gel Electrophoresis: Used for: ___________________Used for: ___________________

This side indicates how many base pairs are in the DNA fragments.

The top indicates the DNA sources.


Gel Electrophoresis: Gel Electrophoresis: Used for: Used for: Comparing DNA samplesComparing DNA samples

This side indicates how many base pairs are in the DNA fragments.

The top indicates the DNA sources.


Gel Electrophoresis:Gel Electrophoresis:

The DNA fragments are sorted based on __________


Gel Electrophoresis:Gel Electrophoresis:

The DNA fragments are sorted based on SIZE.

An electrical current pulls the smaller fragments through the “gel” faster than the larger fragments.

Relationships and BiodiversityRelationships and Biodiversity Gel Electrophoresis:Gel Electrophoresis:The original samples of DNA are “cut” using RESTRICTION ENZYMES.

In the lab, you simulated this by using scissors to cut paper DNA.

Relationships and Biodiversity Relationships and Biodiversity

mRNA codons code for __________mRNA codons code for __________ Example: Example:

– DNA code: CGADNA code: CGA– mRNA code: ________mRNA code: ________– Amino acid chain: (on next page) Amino acid chain: (on next page)

______________, ______________, ______________, ______________, ___________________.___________________.


What causes extinction and loss of What causes extinction and loss of biodiversity?biodiversity?


What causes extinction and loss of What causes extinction and loss of biodiversity?biodiversity?

Change in environmentChange in environmentDiseaseDiseaseHuman activities (pollution, Human activities (pollution,

deforestation)deforestation)Overuse of resources (competion)Overuse of resources (competion)


Loss of biodiversity may be a Loss of biodiversity may be a warning of what?warning of what?


Loss of biodiversity may be a Loss of biodiversity may be a warning of what?warning of what?

ExtinctionExtinctionUnstable environmentUnstable environment


Benefits of biodiversity: Benefits of biodiversity:


Benefits of biodiversity: Benefits of biodiversity:

More food sources for consumersMore food sources for consumersLess chance of extinctionLess chance of extinctionMedicinal resourcesMedicinal resourcesMore stable ecosystemMore stable ecosystem

Diffusion Through a MembraneDiffusion Through a Membrane

What causes the process of What causes the process of diffusion?diffusion?


What causes the process of What causes the process of diffusion?diffusion?

The particles (molecules) move down a concentration gradient from high concentration to low concentration.

This happens because as molecules bump into each other, they are forced to spread out to where there aren’t as many molecules to bump into.


If certain molecules encounter If certain molecules encounter membranes with pores, what can membranes with pores, what can happen? happen?


If certain molecules encounter If certain molecules encounter membranes with pores, what can membranes with pores, what can happen? happen? If the molecules (particles) are small

enough, they will pass through the pores in the membrane.

If they are too big, they cannot pass through the pore.

This is called SELECTIVE PERMEABILITY. Cell membranes are selectively permeable.


What was different between your What was different between your model and a real cell? model and a real cell?


What was different between your What was different between your model and a real cell? model and a real cell?

Not living

No organelles

No proteins

Cannot do active transport (only passive = diffusion)

Living

Has organelles

Has proteins

Does both active and passive transport

BOTH:

Have a selectively permeable membrane

Can do passive transport


What indicators were used in the lab? What indicators were used in the lab?


What indicators were used in the lab? What indicators were used in the lab?

IODINE was used to test for the presence of STARCH. Color changes from amber to blue/black.

BENEDICT’S SOLUTION (blue) tests for GLUCOSE. After heating, it turns orange if glucose is present.


We used test tubes with just water We used test tubes with just water and Benedict’s and another with just and Benedict’s and another with just water and iodine. Why? water and iodine. Why?


We used test tubes with just water We used test tubes with just water and Benedict’s and another with just and Benedict’s and another with just water and iodine. Why? water and iodine. Why?

These two test tubes served as negative controls. This showed us what a negative test would look like.


We also used test tubes with iodine We also used test tubes with iodine and starch, and another with and starch, and another with Bendict’s and glucose. Why? Bendict’s and glucose. Why?


We also used test tubes with iodine We also used test tubes with iodine and starch, and another with and starch, and another with Bendict’s and glucose. Why? Bendict’s and glucose. Why?

These two test tubes served as positive controls. They showed us what a positive test for starch and glucose looked like.


What will happen in this experiment?What will happen in this experiment?


What will happen in this experiment, What will happen in this experiment, and why?and why? The iodine is small

enough to fit through the membrane. It diffuses into the “cell” and turns the starch inside a blue/black color. The starch is too large to diffuse through the selectively permeable membrane, so it cannot diffuse out into the surrounding solution.


Glucose is in the cell below. What Glucose is in the cell below. What will happen, and how do you know?will happen, and how do you know?


Glucose is in the cell below. What Glucose is in the cell below. What will happen, and how do you know?will happen, and how do you know?

When we test the outside solution for glucose using Benedict’s (after heating it), the solution turns orange. This indicates that the glucose diffused out of the cell into the surrounding solution. The glucose was small enough to fit through the selectively permeable membrane.


OsmosisOsmosis

Explain the process that is occurring Explain the process that is occurring in the diagram in the link. in the diagram in the link.


OsmosisOsmosis

Explain the process that is occurring Explain the process that is occurring in the diagram in the link. in the diagram in the link. – The water molecules move from an The water molecules move from an

area of high concentration of water area of high concentration of water (lower solute) to an area of lower (lower solute) to an area of lower concentration of water (higher concentration of water (higher solute). solute).


Which way will diffusion (osmosis) Which way will diffusion (osmosis) occur? (Percents indicate occur? (Percents indicate concentration of water.)concentration of water.)

97%

99%


Which way will diffusion of water Which way will diffusion of water (osmosis) occur? (Percents indicate (osmosis) occur? (Percents indicate concentration of solute.)concentration of solute.)

3%

1%


What is happening here?What is happening here?


What is happening here?What is happening here?When salt water is placed on cells, the water diffuses out of the cells’ cytoplasm into the salt solution. (Water moves from a higher concentration – inside the cell – to a lower concentration – outside the cell.)

If fresh water is placed on the cells again, the water will flow back into the cells (high to low concentration).


Why didn’t the cell walls shrink with Why didn’t the cell walls shrink with the cytoplasm? the cytoplasm?


Why didn’t the cell walls shrink with Why didn’t the cell walls shrink with the cytoplasm? the cytoplasm? – Cell walls are rigid – they provide Cell walls are rigid – they provide

support for plant cells.support for plant cells.


Does this organism live in fresh Does this organism live in fresh water or salt water? Explain how you water or salt water? Explain how you can tell. can tell.


Does this organism live in fresh Does this organism live in fresh water or salt water? Explain how you water or salt water? Explain how you can tell. can tell. Fresh water: The organism contains a

contractile vacuole. Contractile vacuoles serve to pump out excess water from the interior of the cell.

If the organism needs to pump out water, it must have a lower concentration of water on its inside than outside (water keeps diffusing into it). This means that the water outside has fewer solutes. The water must be fresh.

Making ConnectionsMaking Connections

What are the two purposes of this What are the two purposes of this lab?lab?

Making connections between Making connections between data and conclusionsdata and conclusions

Designing a controlled Designing a controlled experimentexperiment


Why is it more accurate to take two Why is it more accurate to take two or three pulse readings and average or three pulse readings and average them? them?


Why is it more accurate to take two Why is it more accurate to take two or three pulse readings and average or three pulse readings and average them? them?

Cancel out errorsCancel out errorsThe data may vary – this makes The data may vary – this makes it more reliableit more reliable


Why were the class results averaged Why were the class results averaged and used? and used?


Why were the class results averaged Why were the class results averaged and used? and used?

More trials means more accurate More trials means more accurate datadata

More subjects means more More subjects means more accurate data, too.accurate data, too.


What is muscle fatigue? What is muscle fatigue?


What is muscle fatigue? What is muscle fatigue? The “tiring” of the muscles through overexertion.


What waste products cause What waste products cause muscle fatigue? muscle fatigue?


What waste products cause What waste products cause muscle fatigue? muscle fatigue?

O2 + glucose

ATP

CO2 + H2O

Capillary

Mitochondria


What waste products cause What waste products cause muscle fatigue? muscle fatigue? CO2, Lactic CO2, Lactic AcidAcid

O2 + glucose

ATP

CO2 + H2O

Capillary

Mitochondria

Or, Lactic acid


Why does muscle fatigue happen?Why does muscle fatigue happen?


Why does muscle fatigue happen?Why does muscle fatigue happen?The more the muscle is used, the more The more the muscle is used, the more

waste products are produced. If the waste products are produced. If the blood isn’t circulating fast enough to blood isn’t circulating fast enough to carry away the wastes, they build up. carry away the wastes, they build up. As a result, the heart pumps faster and As a result, the heart pumps faster and breathing increases to circulate the breathing increases to circulate the wastes out to the lungs faster. (This wastes out to the lungs faster. (This also brings O2 and glucose to the cells also brings O2 and glucose to the cells faster to be used for making ATP.)faster to be used for making ATP.)

Living Environment Lab Review

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Transcript of Living Environment Lab Review