Investigation Design

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Investigation Design Instructions and Rubric Your Task: Design an investigation to collect appropriate evidence to answer the guiding question:Why does (or doesn’t)

the frequency of a physical trait change in a rabbit population in differentenvironments? You can approach this question

in many different ways. There are multiple rabbit traits to focus on (fur color, tail length, teeth length) and many different

types of environments you could test (e.g. environments with and without predators, environments with or without food

limitation, environments with predators at the equator or arctic,and many more!). It is your job to determine what would be

appropriate and sufficient evidence to collect to support your answer to the guiding questionabove.

During Labs #10 and #11 you will have time to brainstorm with a classmate about different elements of the investigation

design, but each student will write up the investigation design assignment individually. By the due date on the course

calendar, you will individually submit an assignment in your own words via the Turnitin link under “Investigation Design” on

the main menu. Features of your design may be similar to a classmate’s if you brainstormed together, but the entire

assignment must be written individually and in your own words. Do not write your assignment in the same room asa

classmate and do not share your written assignment witha classmate. Write your procedure where indicated in Lab 12of the

lab manual or bring a copy of your investigation design to lab so that you can conduct your investigation during Lab #12! This assignment is 10% of your grade.Your investigation design must include sufficient detail that your TA could conduct

the same investigation after reading your assignment. You will be graded based on the rubric below. Your investigation design assignment will consist of the four sections outlined below and each section should address the following questions:

1. Introduction

a) Did you brainstorm with a classmate? If yes, who did you brainstorm with? b) What is the provided guiding question you are trying to answer with this investigation(it’s the same for everyone)?

c) Why is this an important orinteresting question to investigate? (Think about how this investigation connects to the

predictions about traits you made on the field tripin Lab #10.) 2. Experimental Design

a) How will you determine if the frequency of a trait in the population changes over time in different environments? b) What trait will you investigate? (e.g. fur color, tail length, or teeth length?)Why are you interested in this trait?

c) What different environments will you include in your design? (e.g. environments with and without predators,

environments with or without food limitation, environments with predators at the equator or arctic, etc.)Why did you decide to design you investigation this way?

d) There are other variables you can manipulate in the simulation that might influenc the biotic interactions (e.g. Which

allele is inherited as the dominant allele? Where do the rabbits live? When isa selection pressure first introduced?).

How will these variables be controlled or manipulated in your investigationtrials? Why did you make those decisions?

e) How many trials (or replicates) will you conduct? Why is the number of trials important?

f) For how many generations will you need to run the simulation during each trail?How did you determine this# of

generations was appropriate? Why do you think # of generationsis a biologically important variable in this

investigation? 3. Data Collection

a) Will you collect data on a singleresponse variable or multiple response variables (e.g. Total rabbits in population, number of rabbits with white fur, number of rabbits with brown fur, etc)?. Why did you decide to design your

investigation this way?

b) How will you keep track ofand organize the data you collect? Look through your lab manual to review the types of data charts you have used in this class. Draft a data table on the “Data Collection” page of Lab 12 in your manual.

4. Data Analysis

a) How do you predict the frequency of the trait will change in the rabbit population in the different environments you are testing? Why do you think this?

b) Is your prediction grounded in biological concept that we have learned this semester? How so?

c) What type of calculations will you need to maketo summarize your data across multiple trials? Why are these necessary?

d) What type of graph could you createto help make sense of your data? Describe what the graph would look like,

including how you would label the axis, if applicable.

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Grading Rubric

 

 

Criteria Levels of Achievement Proficient Satisfactory Needs Improvement Unsatisfactory

Biology Content 20 Points 18 Points 15 Points 10 Points Use concepts All biological content 1 biology content 2-­­3 biology content 4 or more biology content correctly in Intro and was correct error errors errors Analysis sections

Biology reasoning 30 Points 27 Points 22 Points 15 Points Supported design All reasoning was 1 reasoning error 2-­­3 reasoning errors 4 or more reasoning errors with appropriate appropriate reasoning

Depth of response 20 points 18 points 15 points 10 points Fully explained all Vaguely explained Needed to elaborate Complete lack of depth; thinking thinking on 1 item more on several Answers are limited to bare responses minimum.

Completeness 20 Points 18 Points 15 Points 10 Points Complete all Completed all parts Answered all Completed all 4 Skipped several sub-­­parts or questions in the of all questions parts of all sections but skipped entire sections outline above sections, but 1 or 2 sub-­­parts missed 1 sub-­­ question within a part

Quality 10 Points 8 Points 6 Points 4 Points Creativity, No – or very minor, 1-­­2 noticeable Several noticeable Errors indicated lack of cohesiveness, word almost unnoticeable errors or average errors proofreading; errors made it choice, spelling, – errors; creative design difficult to understand grammar, correct use design of scientific terms

 

 

 

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Interpreting Graphs – Population Growth

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Lab Activity: Interpreting Graphs – Population Growth

 

Use the graph below to answer questions 1–3.

Read each question, and write your answer in the space provided.

1. What type of population growth pattern is shown in the graph above?

 

 

2. Describe the growth of the hypothetical population shown in the graph, beginning with just a few breeding pairs.

 

 

 

3. What is the probable eventual fate of the hypothetical population represented in the graph?

 

 

 

Use the graph below to answer questions 4–7.

 

Read each question, and write your answer in the space provided.

4. Between what years does this graph predict that the human population growth rate will start slowing?

 

 

5. According to this graph, what will the world human population be in 2050?

 

 

6. From 1750 to 2000, which type of population growth model (logistic or exponential) does this graph more closely represent and WHY (provide one piece of data to support)?

 

 

7. If you could continue the graph to the year 3050, predict the type of population growth model this graph would represent. Explain your answer.

 

 

Human Population Growth Name: /50pt Lab

Objectives: You will create a graph of human population growth, analyze factors and conditions that affect it, and use it to predict future growth. Pre-Investigation Questions: Refer to the graph below: Use letters to answer the questions.

1. Refer to the illustration above. Which time period shows exponential growth of the population?

 

2. Refer to the illustration above. During which time period are the birth rate and death rate equal?

 

3. Which time period refers to when a population is in decline?

 

 

 

Statistics on Human Population
Year A.D. Number of People (in billions)  
0 .25  
1650 .50  
1750 .70  
1850 1.0  
1925 2.0  
1956 2.5  
1966 3.3  
1970 3.6  
1974 3.9  
1976 4.0  
1980 4.4  
1991 5.5  
2000 6.0  
2004 6.4  
2010 6.9  
2015 7.2  

 

Instructions for creating your graph.

Place time on the long horizontal (X) axis. Values should range from 0 A.D. to 2010. Place number of people on the vertical (Y) axis. Values should range from 0 to 8 billion. Make sure that your graph is a full page in size, you have the correct unit labels for the X and Y axes, and a title for your graph.

Analysis

4. It took 1649 years for the world population to double, going from .25 billion people to .50 billion people.

a. How long did it take for the population to double once again?

 

b. How long did it take for the population to double a second time?

 

c. A third time?

 

5. What growth model is human population growth for the 1st 1950 years?

 

6. What growth model is human population growth for the last 75 (or so) years?

 

7. Based on your graph, in what year will the population reach 8 billion?

 

The Earth’s Carrying Capacity: Human factors.

Prior to 1950, the death rate was high, which kept the numbers of humans from increasing rapidly. In the 19th Century, the agricultural revolution increased food production. The industrial revolution improved methods of transporting food and other good. In the 20th Century, advances in medicine, sanitation and nutrition have decreased the death rates further. These factors combined to produce the rapid growth of the human population in the 20th century.

As with any population, humans are also limited by factors such as space, amount of food and disease. The carrying capacity is the number of individuals that a stable environment can support. Authorities disagree on the maximum number of people that the earth can support, though the numbers generally range for 8 to 10 billion. As the population approaches its limit, starvation will increase. Some countries have a much higher growth rate than others. Growth rate is the number of people born minus the number of people that die. Compare the growth rates of the following countries

Most countries are trying to reduce their growth rate. Zero population growth means that as many people are being born as there are dying – to achieve zero population growth, each couple would need to have no more than two children (to replace the parents). Even if this number is achieved, the population will continue to grow because the parents will still live on for decades, as their children have children and their children have children…and so forth. The United States reached zero population growth in the 1980’s, and yet the overall population of the US still increases.

Analysis: Use the graph you created and the information above to answer the following questions.

8. What factors contributed to the world’s overall population growth in the last 150 years. List at least 4.

 

 

 

9. Why does a population not level off during the same year it reaches zero population growth?

 

 

 

10. What do you think the Earth’s carrying capacity for humans is?

 

11. If the carrying capacity of the earth was 9 billion people, when would this number be reached (according to your graph)?

 

12. What will happen when the human population exceeds the earth’s carrying capacity? Explain in a few sentences.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

( LABELS: )Population Growth Pyramids.

Analysis: Comprehensive population growth models. Answer the questions completely.

13. What is it called when a population increases at a steady, rapid rate?

 

 

14. Refer to the graph containing Germany. Which age group had the least amount of males?

 

 

15. Refer to the graph containing Guatemala. Which age group has the most individuals?

 

 

16. Which country has a nearly equivalent distribution for each age group?

 

 

17. Label the graph that illustrates a population “DECLINING”.

18. What is your justification?

 

 

19. Label the graph that illustrates a population “EXPANDING SLOWLY”.

20. What is your justification?

 

 

21. Label the graph that illustrates a population “EXPANDING RAPIDLY”.

22. What is your justification?

 

 

23. Label the graph that illustrates a population “STABLE”.

24. What is your justification?

 

 

25. Based upon what you know about these countries, what do you find interesting about the rate of growth of a country and its economy, standard of living, health factors, and other social influences?

 
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Anatomy & Physiology Homework

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Dangerously Thin: A Case Study on the Genetic Code

At 65 years old, Henry Blake was in excellent health and enjoying his first year of retirement. Upon returning from his dream trip to the Great Barrier Reef in Australia, he noticed that his left leg was swollen just inferior to the knee. He already had scheduled an appointment for a complete physical, so he knew that in a few days he would be able to have his physician look at his leg.

Dr. Strickland had been the Blake family doctor for more than 40 years. Knowing that Henry had planned to do some traveling, Dr. Strickland opened with a question that Henry initially found to be a bit out of the ordinary.

“Any chance this swelling showed up after a long flight?”

“As a matter of fact it did,” Henry replied.

“My gut tells me that you may have a clot in that leg, but we’ll have to have a look at it before we’ll know for sure.”

Dr. Strickland knew that Henry’s family had a history of clotting disorders, and he had recently treated Henry’s brother for a deep vein thrombosis (DVT), a disorder that gets its name from the blood clots that form in a vein deep within the leg. A DVT was confirmed by the Doppler ultrasonography results (a test that uses sound to create images of blood flow). Dr. Strickland placed Henry on a “blood thinning” drug called warfarin, which works by preventing clots from forming.

Henry returned to his retirement plans but quickly found himself back in Dr. Strickland’s office after suffering from frequent nose bleeds. A laboratory test called an INR (International Normalized Ratio) was performed. This test measures the time it takes for blood to clot and compares it to an average. The test revealed that the time it took for Henry’s blood to clot was well above what would be expected for the dose of warfarin that he had been placed on. Dr. Strickland immediately took Henry off of his warfarin treatments and asked that he come in every three days for blood tests. Dr. Strickland became concerned when Henry’s abnormal INR results continued long after he had stopped taking warfarin.

Through genetic testing, Henry was found to carry a mutation in a gene for an enzyme called CYP2C9. While the strange name of the gene does not really fully appear to capture the importance of its function, it has a role in breaking down more than 15% of the drugs currently in use, and as many as 35% of people carry a slower acting form of this enzyme. The portion of Henry’s DNA that codes for the CYP2C9 enzyme contains more than 1,400 nucleotides. Henry carries two copies of the CYP2C9 gene, and the tests showed that both of them contain a mutation. On one of these genes, the 1075th nucleotide has been changed from an adenine (A) to a cytosine (C). This mutation converts an ATT triplet code in the coding strand of the DNA molecule to CTT. In Henry’s other CYP2C9 gene, the 430th nucleotide has been changed from a cytosine (C) to a thymine (T). The DNA triplet code CGT in the coding strand becomes TGT as a result of this mutation. Henry was considered a poor metabolizer (PM) because both of his CYP2C9 genes contained a mutation, and therefore he was not making any fully functional enzyme. People who carry two normal copies of the gene are referred to as extensive metabolizers (EM) for their ability to quickly break down drug molecules.

Short Answer Questions

1. Why would someone with this type of mutation be at a much higher risk for overdosing on a prescribed drug?

2. The underlying problem in this case resides in Henry’s “genes.” From what you know about the function of a gene, explain how this problem led to a malfunction in one of Henry’s proteins (the CYP2C9 enzyme).

3. The DNA changes that are described in Henry’s story are changes to the coding strands of the CYP2C9 genes. What is the function of the coding strand and how does it differ from the function of the template strand of Henry’s CYP2C9 gene?

4. Consider the following DNA sequence found on a different portion the coding strand of Henry’s CYP2C9 gene: TTACCGAGA

a. What would be the sequence of the template strand on this portion of the gene?

b. How many triplet codes does this DNA sequence contain?

c. What would be the sequence of the mRNA after this sequence is transcribed?

d. How many amino acids does this portion of Henry’s coding stand actually code for?

5. In the first mutation of the CYP2C9 gene described in Henry’s story, the 1075th nucleotide had changed from an adenine (A) to a cytosine (C). This mutation converts an ATT triplet code in the coding strand of the DNA molecule to CTT. Beginning with this triplet code on the DNA, describe the effect that this change would have on the following:

a. The nucleotide sequence on the template strand of the gene.

b. The mRNA codon that results after this triplet code is transcribed.

c. The anticodon on the tRNA molecule that is complementary to the mRNA codon described above.

d. The amino acid that would be carried by the tRNA molecule described above.

6. In Henry’s other CYP2C9 gene, the 430th nucleotide had changed from a cytosine (C) to a thymine (T). This mutation converts a CGT triplet code in the coding strand of the DNA molecule to TGT. Beginning with this triplet code on the DNA, describe the effect that this change would have on the following:

a. The nucleotide sequence on the template strand of the gene.

b. The mRNA codon that results after this triplet code is transcribed.

c. The anticodon on the tRNA molecule that is complementary to the mRNA codon described above.

d. The amino acid that would be carried by the tRNA molecule described above.

7. From what you understand about enzymes, explain why a change in an amino acid would cause Harry’s enzyme to lose its function.

8. In both of Henry’s mutations, it is the first nucleotide in the DNA triplet code that has been changed.

a. Using the genetic code chart below, create a list of single nucleotide changes in the two affected triplet codes described for Henry’s genes that could occur WITHOUT resulting in a change in the amino acid in the enzyme.

NOTE: The code chart below contains mRNA codons and the amino acids associated with those codons. Your list should contain DNA triplet codes.

image1.png

b. How many triplet code changes did you find that could occur WITHOUT resulting in an amino acid change in the enzyme?

c. Which position (first, second, or third) did the changes occur within the DNA triplet codes you listed above?

d. What would you conclude from the pattern that emerged?

 
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Biology Problem Set Homework

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BICD 110 Fall 2020, Dr. Kiger

Problem Set 8 Lectures 7A-7B

 

Microtubules

 

1. What statement best describes the basis for how/why microtubules are “tubes”?

 

___A. tubulin and tubulin assemble into small filament rings that stack into a tube

___B. tubulin dimers assemble into filaments that spiral into a tube

_X_C. tubulin dimers assemble into parallel protafilaments that fold into a tube

___D. MAPs bind and curve the tubulin dimers so that filament assembly forms a tube

___E. ATPase activity of kinesin motor proteins bends a sheet of protafilaments into a tube

 

2. What is a shared property of both actin and tubulin subunits with respect to microfilament and microtubule dynamics, respectively?

 

___A. predominantly added to filament/protofilament (+) ends.

___B. predominantly added to filament/protofilament (−) ends.

___C. equally efficient at being added to both ends of filament/protofilament.

___D. added along the length within an assembled filament/protofilament.

 

3. During dynamic instability of microtubules, within the tubule…

 

(i)…the -tubulin subunits: (ii)….the -tubulin subunits:

 

___A. undergo ATP hydrolysis ___A. undergo ATP hydrolysis

___B. undergo GTP hydrolysis ___B. undergo GTP hydrolysis

___C. remain locked in GDP bound state ___C. remain locked in GDP bound state

___D. remain locked in ADP bound state ___D. remain locked in ADP bound state

___E. remain locked in GTP bound state ___E. remain locked in GTP bound state

 

(iii) Compare and contrast the above properties of tubulin subunits in microtubule ‘dynamic instability’ to those of actin subunits with microfilament ‘treadmilling’, providing key details. What is similar? What is distinct?

 

 

 

 

 

 

 

4. Define ‘critical concentration’ (Cc) as it relates to microfilament and microtubule formation, as well as to the different ends of the polymers. Define steady state.

 

 

 

 

 

 

 

5. Fill in the blanks.

 

Microtubules are typically not static structures. _____Dynamic instability_____ is the phrase used to describe how a microtubule undergoes alternating periods of rapid growth and shrinkage, called _____rescue_______ and ______catastrophy_________, respectively. These dynamics occur with growth happening at the microtubule ____positive (+)_____ ends, since the ____negative (-)_____ ends are typically inaccessible while stabilized at the ______MTOC_______. At the microtubule minus-ends, you will invariably find the specific microtubule subunit, __________________, which directly interacts with another tubulin subunit, __________________ in -TuRC. Growing microtubule ends are normally stabilized by __________________ ‘caps,’ while ___GTP____ hydrolysis can lead to rapid disassembly.

6. Compare and contrast the proteins, -tubulin and formin (what do they do? how do they do it? where do they do what they do?).

 

 

 

 

 

 

 

 

 

 

 

 

7. Name and describe the organization and roles for the three different major classes of microtubules that contribute to mitosis.

 

Microtubules and Motor proteins

 

8. Motor proteins are what kinds of enzymes?

 

 

 

9. Draw and label a simple cartoon of the general protein domains found in common between the structures for different types of motor proteins. Indicate the ‘motor’ region and what specific types of proteins interact with the different protein domains.

 

 

 

 

 

 

 

 

 

10. Which of the following properties is not shared by all myosins? May be one or more than one answer.

 

___A. the ability to bind ATP

___B. the formation of homodimers

___C. the ability to bind F-actin

___D. the presence of a head domain

___E. the ability to do work

___F. the ability to bind G-actin

 

11. In the model for myosin movement on microfilaments, the power stroke occurs during:

 

___A. binding of ATP.

___B. hydrolysis of ATP.

___C. release of phosphate (Pi).

___D. release of ADP.

___E. the assembly of a myosin thick filament

 

12. Match the cell functions on the right with the specific motor (A-F) most likely involved. You may use an answer more than once or not at all.

 

A. Myosin I ________ Cilia movement

B. Myosin II ________ Cell contraction

C. Myosin V ________ Organelle and vesicle transport (>1 correct!)

D. Kinesin I ________ Microtuble plus-end directed sliding

E. Kinesin 5 ________ Microfilament to membrane tethering

F. Dynein ________ Microfilament plus-end directed vesicle transport

13. All of the following statements describe Kinesin I except:

 

___A. Kinesin I is a (−) end-directed motor.

___B. Kinesin I transports vesicles along microtubules.

___C. Kinesin I binds and hydrolyzes ATP to produce movement.

___D. Kinesin I is composed of two heavy chains and two light chains.

___E. Kinesin is a (+) end-directed motor.

 

14. With respect to motor protein function, specifically what effect would the addition of AMP-PNP (a non-hydrolyzable analog of ATP) have on axonal transport? Why?

 

 

 

 

 

 

 

 

15. You purify what appears (by protein sequence homology) to be an ATPase protein complex that is required in a cell free assay for endosome intracellular transport. You call it Endomytin. You want to determine if Endomytin acts as a motor protein, and if so, to characterize its motor properties. Name three basic criteria (properties or predictions about protein function) that you expect if Endomytin is a motor protein, AND how you would test Endomytin for each of these properties.

 

 

 

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