longtran18

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The Irony of Leadership

December 11, 2018

By: Long Tran, Samantha Palomino, Adam Engle-Sorrell, and Sabrina Chang

Most of the time, when people think of leaders, they think of strong communicators who are outspoken, highly intelligent, and sane. They believe leaders must have the best qualities in order to effectively direct others. However, that may not always be the case. Traits that we often see as negative, such as introversion, low IQ, and psychopathy, can ironically make people better leaders. 

Introversion is often seen as a terrible trait for an effective leader to possess. There is a stigma that they are unsociable and incapable of vocalizing their ideas. Therefore, it is hard to see someone like that leading a group. But in reality, it can actually be a great thing. Introverts generally are more reserved and calm, reflecting on a situation before sharing their thoughts. They are generally more thoughtful and less dominating.[1] These aspects of introversion actually allow an individual to be more people-oriented, reasonable, and approachable. People are more likely to be comfortable with sharing ideas when they feel that a superior is approachable.

Although important figures like Einstein and Shakespeare have high IQs, a study shows that a high IQ does not necessarily make one a good leader. With the pressure of having to be ‘smart’, this study refers back to that expectation and lists its findings with their study. According to the study, high intelligence can make you a better leader but up to a certain point.[2] This research rounded up more than 300 leaders working for different companies in Europe with the average IQ being 110. And, while the study discovered new information, researchers found a positive correlation between intelligence and leadership. The IQ range of this correlation was from 120 and below. With that statistic being present it only reinforces the belief that the brightest among us are less of a good leader.

In another spectrum of personalities altogether, psychopathy is a surprisingly prevalent trait of many leaders that helps in ways that are counter-intuitive to many people. When one imagines a psychopath at work, one tends to think of a creepy man or woman slinking about with criminal intent and a history of suspicious behavior, yet, in reality, many psychopaths tend to be very charismatic and sociable people who use their likability to gain face and move up in the corporate world, manipulating those they need to be successful. While having people like this can be dangerous or immoral, they can be good leaders in the sense that they do a good job with their work and make sure others do.[3] Psychopaths tend to have similar average intelligence to the general population, but, if they are smart enough to move up in the corporate world, they are smart enough to maintain that position without damaging too many others in the process. While intelligence may be highly important for a psychopath to maintain a leadership position, it plays a different role in the average leader.

Overall, there is not necessarily a set list of traits that all good leaders possess. However, the primary trait that seems to over-arch these ironic characteristics is relatability. Workers seem to work better with people that they can relate to.  Relatable leaders make it easy for their subordinates to approach them, thus forming a comfortable work environment. A positive workplace benefits not only the workers, but also the efficiency and productivity of the business. Therefore, a person who can produce such an environment constitutes a good leader. Anyone can develop strong leadership skills as long as they utilize their assets and talents properly. Accordingly, leaders come in all shapes and sizes.

[1] Inam, Henna. “The Good News For Introverted Leaders.” Forbes, Forbes Magazine, 16 Apr. 2018, www.forbes.com/sites/hennainam/2018/04/15/the-good-news-for-introverted-leaders/#6103fa7c192f.

[2] Rachel, Hosie. “High Levels of Intelligence Make You Worse At Being A Leader, Study Finds” Independent, 15 Nov. 2017, https://www.independent.co.uk/life-style/most-intelligent-people-worse-leaders-study-university-lausanne-iq-a8055846.html

[3] Lipman, Victor. “The Disturbing Link Between Psychopathy And Leadership.” Forbes, Forbes Magazine, 3 Dec. 2018, www.forbes.com/sites/victorlipman/2013/04/25/the-disturbing-link-between-psychopathy-and-leadership/#64cdfd554104.

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Discuss/Review Phylogeny

Going through the Phylogenetic Tree slides and questions helped me review phylogeny before the AP test. The concept of phylogeny may seem daunting at first because it is the categorization of billions of species. Phylogeny is not as simple as putting together species with similar phenotypes. Many species look similar, however, they are completely different organisms. For example, sharks and dolphins may seem closely related, but that could not have been further from the truth. Sharks are fish and dolphins are mammals.  Dolphins would be more closely related to dogs than sharks. Due to this, scientists primarily use molecular sequences to compare species to each other. Similar gene sequences imply a closer relationship between species.

Scientists believe that evolutionarily related organisms share a common ancestor. The gene sequences of evolutionarily related species are similar, however, they are different due to diverging mutations of their ancestor’s genes. The two common types of mutations are SNPs and Indels. A SNP is when one base pair in a molecular sequence is changed to another one. An Indel is when nucleotide pairs are taken out or added to a genetic sequence. For gene sequences to be correctly compared they need to be lined up together. 

The phylogeny of a species can be represented with a phylogenetic tree. The tree utilizes splits called branch points to represent the most common ancestor of a set of species. The branch point from which all the other branch points come from is called the root. The root is an overarching ancestor of all the species depicted. A phylogenetic tree can help visualize phylogeny. It makes a complicated relationship between multiple species simple and organized.

In conclusion, I think these resources furthered my understanding, specifically on how to read phylogenetic trees. Thus, allowing me to correctly answer some questions on the AP exam.

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Mealworm Behavior Lab

Introduction

The purpose of this experiment is to experiment with the behaviors of mealworms. This project will utilize stimuli such as platform color, moisture, and food to manipulate the behaviors of mealworms. Through this experiment, I hope to learn the preferences of mealworms and how it affects their actions under certain situations. By using mealworms as a test subject I will get an idea of how behavior can be manipulated and changed.

Materials

·       11 mealworms

·       Black paper

·       White paper

·       Watermelon

·       Paper towels

·       Water

·       Glass dish with a cap

·       Pen

Procedures

1.     Put 11 mealworms in the glass dish and close it with the cap.

2.     For the first test, place black and white paper under the dish, dividing the dish in half.

3.     Record the number of mealworms on each colored side after 10 minutes.

4.     For the second test, remove the different color paper beneath the dish and place a wet and dry paper towel on opposite sides inside the dish.

5.     Record the amount of mealworms accumulated on each paper towel after 10 minutes.

6.     For the third test, remove the paper towels and place a piece of watermelon on one side inside the dish.

7.     Record the number of mealworms around the watermelon after 10 minutes.

Results

Experiment 1 - Color

Experiment 2 - Moisture

Experiment 3 - Food

Conclusion

The general movements of the mealworms usually consisted of moving in a circular motion with the circumference of the dish. The mealworms would try to clump up and be around neighboring worms. Therefore, before each test, I would shake the dish around to randomize the location of each mealworm.

The results of the first experiment show that mealworms prefer black surface over white surfaces. 8 mealworms are on the black side and 3 mealworms are on the white side. The selection of a darker surface may be due to a survival instinct. Darker surfaces may be better for mealworms to avoid predators.

The results of the second experiment show that mealworms prefer the moist towel over the dry towel. All the mealworms moved to the side of the wet towel. Their preference of the moist towel is probably due to their need for water. Water is necessary for mealworms to survive. Thus, it is only natural for them to gravitate towards the moist towel.

The results of experiment 3 display the mealworms attraction to the watermelon. All of the mealworms, except for 1, moved to the side of the watermelon. Similar to the test with moisture, food is a necessary item for survival. Therefore, it is no wonder the mealworms shifted to the watermelon.

In conclusion, this experiment has exhibited the innate instincts of mealworms. These instincts usually took the form of survival tactics. By utilizing these instincts, we can manipulate the movements of the mealworms.

I enjoyed doing this lab because it involved live subjects. Being able to observe and manipulate the actions of the mealworms was a good experience. This lab was refreshing because it also allowed plenty of room for expanding the tests.

If I did this experiment again, I would test multiple variables. For example, I would test color and food together. This test would show if the mealworms would prefer comfort or nutrition more.

One of the errors I made during this experiment was not using a new glass dish for each experiment. Thus, extra unknown variables may have contributed to each experiment. Another error was the lighting I used. The light of the dish was very uneven, so it may have swayed the results.

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Modeling Evolution Lab

Introduction

The purpose of this lab is to use simple origami to demonstrate evolution across generations. In reality, evolution is a phenomenon that spans thousands of years. Conceptualizing evolution and its numerous variables can be complicated. However, this project serves as a way to show evolution is a very short span of time. 

Materials

·       Straws

·       Paper

·       Scissors

·       Meter sticks

·       Tape

·       Die

·       Coin

Procedure

1. Make the origami birds using these instructions:

a. Cut two strips of paper, each strip 2 cm x 20 cm.

b. Loop one strip of paper with a 1-cm overlap and tape.

c. Repeat for the other strip of paper.

d. Tape each strip 3 cm from each end of the straw.  

2. Each bird lays three eggs in each generation.

a. Number the straws 1-3. (Straw 1 is the ancestral bird made in step 1). Mark the head and tail of each straw.

b. The first egg has no mutations. It is a clone of the parent. Use the ancestral for this chick to save time.

c. The other two chicks have mutations. Determine the mutations by flipping your coin and throwing your die. Make your bird according to the information provided in the student manual.

3. Release the birds with a gentle, overhand pitch. Test each bird at least twice. Record the distance each bird flew.

4. Repeat steps 1-3 for 2 more generations. The most successful bird becomes the parent of the next generation. The successful bird has 3 eggs: one without mutations (identical to the parent) and 2 with mutations (see step 2).

Results

(Bird 1 in generation 1 becomes bird 1 in generations 2 and 3.)

(Distance results were measured in meters rather than centimeters.)

Generation 2

Generation 3

Conclusion

The results of this experiment display that the bird with the furthest flying capability passes on its genetics to the next generations. In this case, flying distance is the selective gene that allows the bird to survive and reproduce. Consistently, bird 1 flew the furthest in this experiment with a record flight of 3.02 meters. Bird 1 consisted of two wings with a circumference of 18 cm and width of 2 cm. The dimensions of bird 1 seemed to have struck the perfect balance for flight distance as it beat out the mutants in generation 2. By generation 3, the mutants were essentially bird 1 with little variations of the placement of the wings. Progressively, the birds became more similar to bird 1. This experiment correctly models evolution because the most advantageous bird passed on its genes, and thus the descendants are very similar to it.

There are a couple things I would change if I did this experiment again. To avoid extra variables I would find a way to standardize the throwing of the birds. When I conducted this experiment, the throwing may not have been consistent throughout the whole project. Another error I observed was the construction of the birds. The paper was not cleanly cut or rolled, thus the aerodynamic nature of the birds may have been affected.

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Chinese Fossil Lab

Introduction

           The purpose of this lab is to find the relatives of a Chinese fossil by utilizing DNA sequences from the fossil. DNA research is one of the primary methods used by scientists today to relate the heritage of organisms to each other. By looking at the DNA and taxonomy of specific organisms we can observe the process of evolution.

Material

·       Computer

Procedures

1.     Get the 4 DNA sequences from the College Board website.

2.     Click on the files, select Download, and then save the zip file to your computer. Once the zip file is saved, unpack it by saving the individual file 

3.     Go to https://blast.ncbi.nlm.nih.gov/Blast.cgi and BLAST each gene.

4.     Click on the Saved Strategies from the menu at the top of the page

5.     Under Upload Search Strategy, click on Browse and locate one of the gene files you saved onto your computer

6.     Click View

7.     Analyze the results and cladograms provided by each BLAST.

Results

Gene 1

This gene has a 100% match with a gene from gallus gallus collagen, in common terms a chicken. The cladogram of this gene tells us that this gene is closely related to birds.

Gene 2

This gene has a 99% match with a gene from drosophila melanogaster which is also known as a fruit fly. The cladogram of this gene tells us that this gene is closely related to flies.

Gene 3

This gene has a 95% match with a gene from taeniopygia guttata also known as the zebra finch. The cladogram of this gene tells us that this gene is closely related to zebra finches.

Gene 4

This gene has a 100% match with a gene from alligator sinensis also known as a Chinese alligator. The cladogram of this gene tells us that this gene is closely related to alligators.

Conclusion

Analyzing the results, we can conclude that the Chinese fossil is a species that is similar to alligators and birds. According to this diagram, the Chinese fossil would be between crocodilians and birds. We found with gene 2 that the fossil had traces of fly genes. My placement of the fossil in the diagram makes sense, because it still has a close connection with insects. Thus, the graph shows us that the fossil was a heterotroph and has a vertebrae. With the information about the fossil’s relation with other animals, we could infer many things. It is possible that the fossil has wings, feathers, or even scales. Initially, I did not think that alligators and birds were related. Experimenting with these genes was a pleasant surprise, because it showed me relationships between different animals. In conclusion, I found this lab very insight due to its use of professional tools.

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Lunar New Year Celebration

Bellarmine’s Lunar New Year was an amazing experience. I was involved in the celebration as a server. The celebration started off with a lion dance. Lions, consisting of two people wearing a colorful lion costume, coordinated a spectacular performance. The most exciting part of the dance was when a head of cabbage was raised on a stick. One lion then proceeded to jump and eat it. Rituals like this have been performed throughout human history. Ancient civilizations used rituals to speak to their respective gods. This Asian dance parallels the animism seen in Native American and African cultures. Religious and cultural traditions helped advance humanity and society by gathering people under one belief and community. The cooperation required for these rituals allowed humanity to elevate ourselves to who we are today.

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restrictionDigest Lab

Introduction

The purpose of this lab is to cut lambda into fragments using restriction enzymes. A restriction enzyme is a protein that recognizes a specific nucleotide sequence and cuts the DNA at that specific site. In this lab, I will observe how certain restriction enzymes cut DNA in different manners. I will be using an electrophoresis machine to make the cuts of DNA visible to the human eye. A control group without a restriction enzyme added will be used as a baseline for this experiment.

Materials

·       Uncut lambda DNA

·       Pstl restriction digest

·       EcoRl restriction digest

·       HindlIl restriction digest

·       Sample loading dye

·       Micropipette

·       Bed of ice

·       Water

·       Electrophoresis machine

·       Agarose gel with a line of cavities

Procedure

1.      Obtain micro test tubes that contain each enzyme stock solution, lambda DNA, and restriction buffer. Keep all the stock solutions on ice.

2.      Obtain one of each colored micro test tubes and label them as follows: yellow tube: L (lambda DNA) violet tube: P (PstI lambda digest) green tube: E (EcoRI lambda digest) orange tube: H (HindIII lambda digest)

3.      Using a fresh tip for each sample, pipet the reagents into each tube according to the table below:

4.      Mix the components by gently flicking the tube with your finger and tapping gently on the table to collect liquid to the tube bottom. Pulse-spin the tubes in a centrifuge to collect all the liquid to the bottom, or tap them gently on the benchtop.

5.      Place the samples in the ice tray.

6.      Remove the digested DNA samples from the ice tray.

7.      Add 2 µl of sample loading dye into each tube. Mix the contents by flicking the tube with your finger. Collect the sample at the bottom of the tube by tapping it gently on the table or by pulse-spinning in a centrifuge.

8.      Fill the electrophoresis chamber on the agarose gel and cover the gel with 1x TAE buffer (about 275 ml of buffer).

9.      Check that the wells of the agarose gels are near the black (–) electrode and the bottom edge of the gel is near the red (+) electrode.

10.   Load 10 µl of each sample into separate wells in the gel chamber in the following order: Lane Sample 1 M, marker (clear tube) 2 L, uncut lambda DNA (yellow tube) 3 P, PstI lambda digest (violet tube) 4 E, EcoRI lambda digest (green tube) 5 H, HindIII lambda digest (orange tube) 8. Carefully place the lid on the electrophoresis chamber. Connect the electrical leads into the power supply, red to red and black to black.

11.   Turn on the power and run the gel at 100 V for 30 minutes. Tap + – + –

12.   When the electrophoresis run is complete, turn off the power and remove the top of the chamber. Carefully remove the gel and tray from the gel box. Slide the gel into the staining tray.

13.   Add 120 ml of 1x Fast Blast DNA stain to the staining tray (2 gels per tray). Let the gels stain overnight, with gentle shaking for best results.

14.   Pour off the water out.

15.   Record results.

Results  

Conclusion

From this experiment, we were able to determine the base pairs that each restriction enzyme presented to us from the distance that each of the lambdas moved from the well with different restriction digests. As the distances of the DNA bands increase, the number of base pairs present in that specified fragment decreases. The results prove that as the strand of DNA gets longer, it travels through the gel slower, therefore it will be closer to the original starting point. All of the added restriction enzymes created similar amounts of base pairs, however, PstI created the most amount of base pairs at 23,000 base pairs. HindIII, EcoRI, and the lambda without enzymes were equal at 22000 base pairs.

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pGLO Lab

Introduction

This lab serves as an introduction to biotechnology. Throughout this lab, we will be dealing with manipulating bacteria. The goal of this lab is to make strands of E.coli glow in the dark under a black light. This lab taught me the importance of precision and accuracy. For example, if the wrong amount of a substance is used or the timing of a stage is off, this lab will not be successful. Thus, this lab was really eye-opening to what a profession lab experiment would be like.

Materials

·       E. coli starter plate

·       4 Poured agar plates

·       Transformation solution

·       LB nutrient broth

·       Inoculation loops

·       Pipets 5

·       Foam microtube holder/float 1

·       Container full of crushed ice

·       Marking pen 1

·       Rehydrated pGLO plasmid 1 vial

·       Ice water bath

·       Incubator

Procedure

1.      Label one closed micro test tube +pGLO and another -pGLO.

2.      Open the tubes and using a sterile transfer pipet, transfer 250 µl of transformation solution (CaC12 ).

3.      Place the tubes on ice.

4.     Use a sterile loop to pick up a single colony of bacteria from your starter plate. Pick up the +pGLO tube and immerse the loop into the transformation solution at the bottom of the tube. Spin the loop until the entire colony is dispersed in the transformation solution. Place the tube back in the tube rack in the ice. Using a new sterile loop, repeat for the -pGLO tube.

5.     Examine the pGLO plasmid DNA solution with the UV lamp. Note your observations. Immerse a new sterile loop into the plasmid DNA stock tube. Withdraw a loopful. There should be a film of plasmid solution across the ring. This is similar to seeing a soapy film across a ring for blowing soap bubbles. Mix the loopful into the cell suspension of the +pGLO tube.

6.     Incubate the tubes on ice for 10 minutes.

7.     While the tubes are sitting on ice, label your four agar plates as follows: Label one LB/amp plate: +pGLO; Label the LB/amp/ara plate: +pGLO; Label the other LB/amp plate: -pGLO; Label the LB plate: -pGLO.

8.     Using the foam rack as a holder, transfer both the (+) pGLO and (-) pGLO tubes into the water bath, set at 42 °C, for exactly 50 seconds. Make sure to push the tubes all the way down in the rack so the bottom of the tubes stick out and make contact with the warm water. When the 50 seconds are done, place both tubes back on ice. Incubate tubes on ice for 2 minutes.

9.     Remove the rack containing the tubes from the ice and place on the bench top. Open a tube and, using a new sterile pipet, add 250 µl of LB nutrient broth to the tube and reclose it. Repeat with a new sterile pipet for the other tube. Incubate the tubes for 10 minutes at room temperature.

10.  Tap the closed tubes with your finger to mix. Using a new sterile pipet for each tube, pipet 100 µl of the transformation and control suspensions onto the appropriate plates.

11.  Use a new sterile loop for each plate. Spread the suspensions evenly around the surface of the agar by quickly skating the flat surface of a new sterile loop back and forth across the plate surface.

12.  Place the all the plates upside down in the 37°C incubator until the next day.

13.  In the next day, observe each plate under a UV light.

Results  

Conclusion

The only two agar plates that showed noticeable transformations were -pGLO LB and +pGLO LB/amp. The -pGLO LB agar plate presented a large growth of E.Coli that was the most out of any of the plates. The +pGLO LB/amp did not grow as much as expected, but it developed an ability to glow under a UV light. It was interesting to see what combination of substances produced a change in the E.coli. It did not seem like one specific substance was causing the changes, rather a combination of different substances produced different results. Thus, for later tests, different combinations of substances like -pGLO LB/amp/ara or +pGLO LB should be fascinating to experiment with.

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Hardy-Weinberg Lab

Introduction

The purpose of this lab is to see how alleles change throughout multiple generations. For this specific project, I will be making the homozygous recessive gene lethal. Therefore, all organisms that are homozygous recessive will die and fail to reproduce. Since these organisms will not be able to reproduce their genes will not contribute to the next generation. My hypothesis is that the recessive allele will die off or at least become very small after multiple generations.

Materials

Microsoft Excel

Procedure

Create an Excel spreadsheet that randomly generates 50 pairs of gametes based on an inputted percentage.

Total up the AA, AB, and BB zygotes.  (A representing the dominant allele and B representing the recessive allele)

Within the spreadsheet, multiply the BB total by 0 so BB does not contribute to the total amount of B alleles.

With the information gained from the previous 2 steps, total up the A and B alleles.

Use the totals of A and B alleles for the chance of each respective allele appearing in the next generation.

Make 10 generations with a population of 50 in each generation.

Experiment with higher and lower percentages for the probability of each allele appearing in the first generation.

Record findings.

Results

First Generation Starting with 50% A(dominant allele) and 50% B(recessive allele)

First Generation Starting with 10% A(dominant allele) and 90% B(recessive allele)

Conclusion

My results were very interesting, to say the least. Starting with 50% A and 50% B in the first generation with more B alleles in the last generation than starting with 10% A and 90% B. Mr. Wong was very confused with these results when I was presenting my spreadsheet to the class. However, I believe this is because starting with 90% B had a higher chance of producing BB than starting with 50% B. Since BB is lethal and does not contribute to the next generation, having more BB would lower the amount of B alleles faster than having less. Therefore, less B alleles in the first generation would prove better for the survival of the allele in later generations, because AB, which is not lethal, would be more popular than BB. My results prove my hypothesis fairly clearly. In both scenarios, the total amount of B alleles is significantly lower than A alleles because having a lethal homozygous recessive gene decimates the recessive allele amount. Allele frequencies change depending on the parents. The more desirable allele will be more likely to be passed onto the next generation. In this example, the non-lethal allele will be more likely to be passed on to the next generation. One fix that would make my model more accurate is by increasing the population size to a much larger number.

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Corn Genetics Lab

Introduction

The purpose of this lab is to test if data collected from an ear of corn is due to chance or relevant through chi-square analysis. This will be done by comparing the actual number of kernels to the expected number of kernels.

Materials

Ear of corn

Procedure

Count the kernels of corn and categorize them into purple smooth, purple shrunken, yellow smooth, and yellow shrunken.

With chi-square analysis, determine the deviation of your data from a 9:3:3:1 ratio.

Results

Conclusion

With my calculations of chi-square analysis, I can confidently say that my observed results correlate with my expected results. Thus, the parents of the corn I experimented on both were PpSs. Only the offspring of two PpSs parents would result in a 9:3:3:1 ratio. My results were so close to the expected number of kernels that there is an extremely low possibility that this is because of chance.

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Mitosis Lab

Introduction

           The purpose of this lab is to see if a specific substance causes cells to go into mitosis. The experiment will consist of counting and categorizing the cells of six different views (three regular samples and three treated samples of onion root tip) into either mitosis or interphase. The regular onion root tip will act as a control as opposed to the treated onion root tip. After gathering the appropriate data, I will proceed to calculate the significance of the results.

Materials

·       Treated onion root tip

·       Regular onion root tip

·       Microscope

·       Camera

Procedure

1.     Place the treated onion root tip under the microscope.

2.     Take pictures of three different views of the treated sample.

3.     Switch the treated sample for the regular sample.

4.     Take pictures of three different views of the regular sample.

5.     Categorize the cells in each picture into interphase or mitosis.

6.     Calculate the significance using chi-square.

Results

Treated Sample Views:

Regular Sample Views:

Class Data:

Conclusion

           After calculating the chi-square value of approximately 0.1009 and analyzing with the chi-square chart, I came to the realizing that the results were not significant. Therefore, the substance did not have significance in terms of causing mitosis. Results that prove the substance’s artificial mitosis causing ability must have been due to random chance. Mr. Wong later revealed to me that he gave me two of the same samples and that there was no treated sample. Hence, the samples had the same rate of mitosis.

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Photosynthesis Lab

Introduction

The purpose of this lab is to test the relationship between different color lights and photosynthesis. The different colors that will be tested are no color, green, and red. The rate of photosynthesis will be based off on the time it takes for the leaf disks to rise to the top of the solution.

Materials

·       Baking soda

·       Liquid soap

·       2 plastic syringes without needle

·       Living leaves

·       Hole puncher

·       2 clear plastic cups

·       Timer

·       Lamp

·       Red film

·       Green film

Procedure

1.     Prepare 300 mL of 0.2% bicarbonate solution for each experiment.

2.     Pour the bicarbonate solution into a clear plastic cup.

3.     Put one drop of a dilute liquid soap solution to the solution in the cup. It is critical to avoid suds.

4.     Cut 10 uniform leaf disks. Avoid major leaf veins.

5.     Remove the plunger from the syringe.

6.     Place the 10 leaf disks into each syringe barrel.

7.     Put the plunger back into the syringe.

8.     Push in the plunger until only a small volume of air and leaf disk remain in the barrel.

9.     Pull a small volume of sodium bicarbonate plus soap solution from your prepared cup into the syringe.

10.  Tap each syringe to suspend the leaf disks in the solution. Make sure no air remains.

11.  Create a vacuum by holding a finger over the narrow syringe opening while drawing back the plunger. Hold this vacuum for about 10 seconds.

12.  While holding the vacuum, swirl the leaf disks to suspend them in the solution. Now release the vacuum by letting the plunger spring back.

13.  Pour the disks and the solution from the syringe into the plastic cup.

14.  Place the cup under the lamp and start the timer.

15.  Record data of the floating for 10 minutes or until all the disks float.

16.  Repeat the experiment under green and red light.

Results

Conclusion

The control group in this experiment was using regular light. It took 3 minutes and 45 seconds for all ten disks to rise to the top. Not surprisingly, the green light did not show effective photosynthesis. At the end of the 10 minutes, only one disk slightly rose under green light. Leaves do not readily absorb green light, rather it reflects green light. The last test used red light. Red light is the best color light for photosynthesis. However, after 10 minutes under red light, only one leaf rose to the top. A confounding variable in this experiment is the leaves were crushed during hole punching.

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Investigation 4 Blog Report

Introduction

The purpose of this lab is to observe and test how osmosis occurs in different situations. The first situation will utilize agar cubes. The second situation will use dialysis tubes to represent membranes. The final test will be directly tested on plant cells.

Procedure 1

In this part, three cubes of agar, each with a different size, were put into small jars filled with NaOH. The three cubes were 0.5, 1, and 2 inches. The jars were all the same size and had the same amount of NaOH. When the cubes were put in the jar with NaOH, they would turn clear at varied rates. As the cubes sat in their jars, I measured when each cube transformed.

The 0.5 inch cube was the fastest to turn clear, taking 8 minutes and 36 seconds. The 1 inch cube was the next to turn clear, taking 12 minutes and 5 seconds. While the 2 inch cube took the longest to turn clear, taking more than 16 minutes.

The smaller the cubes were, the faster they reacted. The surface area to volume ratios of the smaller cubes were larger than the bigger cubes. For example, the surface area to volume ratio of the 0.5 inch cube is 12, while the surface area to volume ratio of the 2 in cube is 0.1. With these results, I predict that a larger surface area to volume ratio allows a reaction to occur more rapidly.

Before:

Time-lapse:

Procedure 2

In this part, four different dialysis tubes filled with a solution were placed in cups filled with another solution. The first test consisted of a tube of H2O and a cup of H2O. After 10 minutes, This tube was weighed, and it had the same weight as before. The second test consisted of a tube of NaCl and a cup of H2O. Again, when 10 minutes passed, the tube was weighed. This time, the tube was heavier. The third test consisted of a tube of sucrose and a cup of H2O. Like the previous tests, 10 minutes passed before we weighed the tube. The resulting tube weighed more than before. A fourth test was done. However, in order to avoid causing Mr. Wong distress, I will ignore the results of this test. This test did not go the way Mr. Wong wanted so it stressed him out. Luckily, a Diet Coke was in close proximity to calm his nerves.

Water goes into the tied dialysis tubes when there is a lower concentration inside. The first test had an equal concentration of water on the inside and outside. Therefore, no change occurred in terms of the weight of the bag. The other two tests showed that the bag was heavier because they had a low concentration inside.

*Note: Pictures and videos are not available to avoid giving Mr. Wong flashbacks of this horrible time*

Procedure 3

In this part, NaCl was put on an elodea leaf to break down its cell wall. The first thing I did was, I observed the elodea leaf prior to any testing. The elodea leaf had densely packed green structures inside each cell. The cell wall contained the contents and separated each cell from each other.

After exposing to the leaf to NaCl, no apparent changes occurred that are visible to the naked eye. However, under the microscope, I saw that the cell wall disappeared, and the green dots were scattered rather than how organized they were before. The high concentration of NaCl used in this experiment destroyed the cell wall as the leaf absorbed it.

Time-lapse:

Before:

After:

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Your Inner Fish

           When it comes to ancient ancestors, we often compare ourselves to primates. Besides the gap in intelligence, the similarities between humans and apes are not so drastic. However, if we go back much further in the past, history will show humans descended from fish. Fish and humans seem completely different in every way. They have different body structures, respiratory methods, and habitats. Logically, it is highly plausible that land dwelling creature originated as fish due to the prominence of water on the earth. In Neil Shubin’s book, Your Inner Fish, he seeks to prove the ancestral connection between fish and humans by analyzing fossils and comparing traits such as limb formation, teeth characteristics, and genetic triggers.

           The primary question that drives the beginning of Your Inner Fish is why do all terrestrial creatures have the same bone pattern in their limbs. Shubin hypothesizes that terrestrial creatures share a common ancestor with limbs that was closely related to fish. After a long process of researching and exploring, Shubin discovers the fossil of an amphibian and fish hybrid, this creature will later be named Tiktallik. At the time of Tiktallik’s life, creatures resided in water and ate each other for survival. In order to avoid predators, Tiktallik developed limbs to move on shallow marshes and rivers. The evolutionary cultivation of the small limbs of Tiktallik would be the genesis of terrestrial creatures. All the current land animals today, even humans, owe their limbs to their ancient ancestor Tiktallik. A connection is also made about Tiktallib being one of the earlier creatures with a neck. Fish do not have necks, so their head must move with their body. The neck of Tiktallik displays the change from fish to amphibian. This fossil brings a whole new understanding of not only humanity’s ancestral lineage but all terrestrial creatures.

           The author does not only cover physical human links to fish but also genetic links. Geneticists discovered a gene called the Sonic hedgehog gene that controls the orientation of the ends of a creative. The Sonic hedgehog gene is similar to the gene that controls the orientation of limbs, therefore it is only active in limbed organisms. The Sonic hedgehog gene can be triggered by an injection of Vitamin A. Scientists experimented with this idea by injecting a shark embryo with the protein made from the Sonic hedgehog gene of a mouse. As a result, the shark embryo reacted to the injection the same way a mouse would react to an injection of Vitamin A. Since the reaction was the same for both animals, it means that sharks and mice share a common genetic trigger that affects the development of the embryo. This finding has furthered the connection between terrestrial animals and fish. Other genes that present a link are Pax 2 and Pax 6 which are necessary for the formation of ears and eyes. Aquatic creatures do not have ears so they do not have the Pax 2 gene. However, a study on jellyfish explains that they have eyes without the Pax 2 and Pax 6 genes. This is possible because jellyfish have a gene that is a combination of the Pax 2 and Pax 6 genes. Considering that marine life has these genes, it is believed that the genes have been passed down to humans.

           Overall, Your Inner Fish by Neil Shubin explains the aquatic lineage of humans in an interesting through adventure and discovery. Yet, the end of the book begins to drag and lose focus. For example, Shubin goes on a tangent about how alcohol affects vision. Whenever he deviates from the topic of the relationship between ancestors and humans, the focus is blurred and the reading becomes tiresome. Nonetheless, Shubin has taught me much about the correspondence of humanity and nature. Everyone is connected one way or another.

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Water and Life

           Water is the most abundant compound in the world and at the same time the most essential substance to all life. People often mistake the complexity of the compound. With just two hydrogen atoms and one oxygen atom in each molecule, it offers a great variety of properties. For example, the polarity of water holds it together with cohesion, allowing for its surface tension. Molecules of water are bonded in such an organized fashion that it behaves as though it was coated with an invisible film. Moreover, the high specific heat of water causes it to take more energy to change temperature than iron. Its high specific heat traces back to hydrogen bonding as a high level of heat is needed to break the hydrogen bonds. This property stabilizes the temperature of large bodies of water in order to properly sustain marine life. Strong hydrogen bonds also contribute to water’s high heat of vaporization. About 580 cal of heat is necessary to vaporize 1g of water at 25 degrees C. In addition, water’s ability to be a solvent enables it to change its pH level depending on what is dissolved in it. Not only can ionic compounds dissolve in water but compounds made up of nonionic polar molecules are capable of dissolving in water too. However, this leads to problems of ocean acidification which could damage the species diversity of the ecosystem. Water covers approximately 70 percent of the earth, playing a major role in all environments. Hence, protecting the world’s water proves vital to the preservation of life.

           Although there are countless locations in the world that are incapable of sustaining life, organisms called extremophiles have been able to survive in those places. Astrobiologists have become interested in studying extremophiles because their existence is very telling of the possibility of life on other planets. The other planets in our same solar system have been deemed incapable of facilitating most of Earth’s life. If extremophiles are able to live under extreme conditions, it brings hope that there may be similar organisms in other planets. By studying extremophiles, we could learn about how to survive in difficult situations and apply that knowledge to space exploration. All known life needs water and that is no excuse for extremophiles, ruling out any planet that has no water at all. Nevertheless, life comes in all different forms, so who knows what types of other organisms there are.