Is Sexual Reproduction Important?

     In one of the chapters in Dr. Tatina's Sex Advice, the author writes about how sex is important in life.  This book was presented in a way not only in a dry way of reading another book, but instead the author wrote the book as a conversation between an asexual reproducing species and sexual producing species.  The book was not only a conversation, it was a daytime TV show argument between the asexual producing species and the sexual producing species.  The main argument between the two groups were about the importance of sex.  The two sides believe in the opposite beliefs and the chapter describes the argument between the two.

     Sex is important because this process is the best way to maintain a functioning and healthy population.  Sexual reproduction has many benefits.  Sexual production creates genetic variation, can allow parents to raise young to ensure survival, and creates competition which allows the best to survive.  There are some costs, however.  Sexual reproduction requires a lot of energy and time, exposes you to parasites or disease, creates genetic combinations that can be bad, and not everyone can reproduce.  There are many benefits and costs, but the benefits outweigh the costs to show that sex is important in life.  There are also benefits and costs for asexual reproduction.  The benefits of asexual reproduction is that it is easy, takes a short amount of time, does not require two people, and can makes lots of offspring.  There are costs to asexual reproduction.  The costs are that there is no genetic variation that can lead to no resistance to change and that the species is more likely to go extinct if a new pathogen attacks or the environment changes.

     There were many arguments made, given that there are two sides trying to prove their respective points.  The first example of an argument says, "Sex may be fun, but cloning is much more efficient." (215)  The asexual reproduction strength is that they can make a lot of offspring in a short amount of time.  Another argument is given by the asexual side, "All else being equal, an asexual female who appears in a population should have twice as many offspring as her sexual counterpart." (215)  This quote shows how efficient asexual organisms are in producing offspring.  The amount is not just a little more than sexual reproduction, it is around two times more.  Another quote shows how productive asexual organisms are, "Each female must have two children for the population to remain the same size ... however, each female needs to have only one child for the population to remain the same." (215)  Again, the asexual organism is proving its point that the production and efficiency of the asexual reproducer can do less work and the sexual producer needs to do more work to remain constant.  This chapter gets evened out as the asexual producer fires arguments at the sexual reproducers.  A quote that supports the sexual production side states, "But although asexuality often evolves - it pops up in groups from jellyfish to dandelions, from lizards to lichens - it rarely persists for long." (216)  This quote shows one of the weaknesses of the asexual producers.  Asexual organisms do not last for long even though they can make many very fast and efficiently.

     I thought that this chapter was very interesting, but I did not know much about sexually and asexually producing in order to make a good viewpoint.  I thought some topics were confusing and I could have understood this topic better if I knew every single thing going on.  I want to learn about how scientists could make the sexually production organisms have less costs so that we would run in to less errors or problems.

Unit 3 Reflection

     In this unit, we learned about cells, how they work, photosynthesis, and cellular respiration.  The major theme I found in this unit was how cells evolve around different functions that keep us alive.  This unit's essential question was "How do macromolecules serve as building blocks of cells?"  In this unit, we first learned about the different parts of the cells and how they function.  On example would be how cells make proteins.  The cells first get the DNA from the nucleus.  Then the ribosomes make the proteins.  After that, the proteins are sent to the endoplasmic reticulum, or also known as ER, where they are finished.  Once the ER, or endoplasmic reticulum, finishes on working on the proteins, the proteins are sent to the golgi apparatus where they send the protein off out.  This concept is one thing we learned about in Unit 3.  After learning about the basics of how a cell works, we then learn how the cells function in different ways such as photosynthesis and cellular respiration.  Photosynthesis produces oxygen and glucose from sunlight, water, and carbon dioxide while cellular respiration takes in oxygen and glucose to make ATP, water, and carbon dioxide.

     In this unit, I learned more about myself and how I learn material.  I had many strengths and success that I did not have the previous unit but I also had some weaknesses and setbacks that could really hurt me later on.  One strength I gained this unit was to learn how the vodcasts work and how to take notes in the most efficient way.  I also learned more about how this class works so I can do homework and prepare for this class easier than in Unit 1 or Unit 2.  In this unit, I did not only have strengths, I also had many weaknesses and setbacks.   An example of one of the setbacks or weaknesses I had was that the material had many specific detail and I was too focused on the many details, but I really should get the big picture and what is going on before I study all the details on how it really works.  From all my experience in this class, I learned many things about myself and how I work as a student.  I am a better student than yesterday because I know more information about biology and I learned more about how I function as a student.  I am a better student because I learned more about myself and the content in biology.

     In this unit, I learned many interesting things such as photosynthesis and cellular respiration.  I do have some lingering questions after this unit came to an end.  I am curious about how cellular respiration and photosynthesis can work together or what if both things did not have enough of their resource to make enough of their product.  I also wonder about when animals, such as cows, eat plants, do the photosynthesis happen in their body or do the thylakoids do not get enough of what they need to start photosynthesis.

Microscopic Organism Lab Conclusion

This photo was taken at x650.  One thing unique about this cell is that these look like pink star's like Patrick from Spongebob.  One thing my partner and I noticed was that there was a green star, but then inside the green star contained a red or pink circular shape thing inside the green star cell.  This amoeba is eukaryotic and is heterotrophic.

This photo was taken at x650.  One unique characteristic about this cell is that the cell looks like blue rice.  One observation my partner and I had about this cell was that you could clearly see the small dark black nucleus clearly from the microscope.  This euglena cell is eukaryotic and autotrophic.

This photo was taken at x400.  One thing unique about this cell is that there are no chloroplasts in this cell.  One observation my partner and I noticed was that there are little dots that are chained together to form lines.  This cyanobacteria is prokaryotic and autotrophic.

This photo was taken at x650.  I noticed that the bacteria cell is a lot smaller compared to the other cells my partner and I had observed.  One thing I observed about this cell is that there is not only one kind of cell, there are three types of cells compared to normal cells that usually have only one kind.  This bacteria cell is prokaryotic and can be autotrphic and heterotrophic.

This picture was taken at x650.  One thing my partner and I noticed about this slide was that this cell looks really scattered and does not like like one cell.  One observation my partner and I had while looking at this cell was that there is a dark spot near next to each cell.  This spirogyra cell is eukaryotic and is autotrophic.

The power of the microscope was x650 when this photo was taken.  One thing unique about this slide is that there is one section of the cell that is pink and then there is another section in the cell that is green.  One thing that my partner and I noticed was that you could see the different circular parts of the cell.  This ligustrum cell is prokaryotic and is autotrophic.

The power of the microscope is x650.  My partner and I noticed that this cell was different from the others because the cell has a nucleus that is black.  One observation my partner and I had was that you could clearly see the different strands in the cell.  This animal cell is eukaryotic and is heterotrophic.

     For each organism, I was able to identify different parts.  In the animal cell, I was able to identify single muscle fibers, striations, and the nucleus.  In the ligustrum, I was able to identify the chloroplasts, epidermis cell, and the vein.  In the spirogyra, I was able to identify the chloroplast, cell wall, and cytoplasm.  In the bacteria cells, I was able to identify the three types of bacteria cells named the coccus, bacillus, and the spirilum.  In the cyanobacteria, I was able to identify one single cell out of all the cells linked together to form a larger piece.  In the euglena, I was able to identify the nucleus, chloroplasts and a faint sign of the flagellum.  In the amoeba, I was able to identify the nucleus, cell membrane, pseudopods, and the cytoplasm.  The eukaryotic cells were able to be identified with a nucleus.  The prokaryotic cells were identified without a nucleus.  Most of the autotrophs were smaller and less complex.  The heterotrophic were more complex and some evne had other autotrophs inside them.

Photosynthesis Virtual Labs

Photosynthesis Virtual Labs

Lab 1: Glencoe Photosynthesis Lab

http://www.glencoe.com/sites/common_assets/science/virtual_labs/LS12/LS12.html

Analysis Questions

1. Make a hypothesis about which color in the visible spectrum causes the most plant growth and which color in the visible spectrum causes the least plant growth?

If visible light provides a spectrum of red through violet, then red, blue, and violet light will make the plant grow the fastest and green and yellow light will make the plant grow the slowest.

2. How did you test your hypothesis? Which variables did you control in your experiment and which variable did you change in order to compare your growth results?

I tested my hypothesis by adding different plant seeds and then measuring the different heights the plants grew over 30 days with different color light.  The controlled variables were the duration, same unit of measure (cm), same amount of light, and same amount of seeds.

Results:

Filter Color	Spinach Avg. Height (cm)	Radish Avg. Height (cm)	Lettuce Avg. Height (cm)
Red	17.3 cm	12.67 cm	11 cm
Orange	15 cm	8.67 cm	7.3 cm
Green	2.3 cm	2 cm	3.67 cm
Blue	19.3 cm	15 cm	12.67 cm
Violet	16 cm	10.3 cm	9.3 cm

3. Analyze the results of your experiment. Did your data support your hypothesis? Explain. If you conducted tests with more than one type of seed, explain any differences or similarities you found among types of seeds.

The data I gathered during the duration of this experiment supported my hypothesis that red, blue, and violet light would make the plants grow faster.  For each category of plant seeds, the red, blue, and violet grew much larger than the other light colors.  The red plant heights were 17.3 cm, 12.67 cm, and 11 cm for spinach, radish, and lettuce, respectively.  The blue plant heights were 19.3, 15 cm, and 12.67 cm for spinach radish, and lettuce, respectively.  The violet light heights were 16 cm, 10.3 cm, and 9.3 cm for spinach, radish, and lettuce, respectively.  The green light plants did not even reach 5 cm for any of the plant seeds.  Among all the seeds, I noticed that all the red,  blue, and violet light plants grew the highest and the green light plants grew the least.

4. What conclusions can you draw about which color in the visible spectrum causes the most plant growth?

I can conclude from this experiment that the plants light spectrum absorb the most light from the ends of the spectrum.  The wavelengths should either be really short or really long.

5. Given that white light contains all colors of the spectrum, what growth results would you expect under white light?

Under white light, I would expect the averages of all the colors because the plants will absorb all the different colors in a different way, so the white light would reflect the average.

Site 2: Photolab

http://www.kscience.co.uk/animations/photolab.swf

This simulation allows you to manipulate many variables. You already observed how light colors will affect the growth of a plant, in this simulation you can directly measure the rate of photosynthesis by counting the number of bubbles of oxygen that are released.

There are 3 other potential variables you could test with this simulation: amount of carbon dioxide, light intensity, and temperature.

Choose one variable and design and experiment that would test how this factor affects the rate of photosynthesis. Remember, that when designing an experiment, you need to keep all variables constant except the one you are testing. Collect data and write a lab report of your findings that includes:

• Question
• Hypothesis
• Experimental parameters (in other words, what is the dependent variable, independent variable, constants, and control?)
• Data table
• Conclusion (Just 1st and 3rd paragraphs since there's no way to make errors in a virtual lab)

*Type your question, hypothesis, etc. below.  When done, submit this document via Canvas.  You may also copy and paste it into your blog.

Question:  Will light intensity affect the amount of oxygen bubbles that will be released?

Hypothesis:  If more light will produce more oxygen, then the amount of oxygen bubbles will increase with higher light intensity.

Experimental parameters:

30 seconds

25 degrees

Blue light

Least amt of carbon dioxide

• Dependent variables: Amount of oxygen bubbles produced 
• Independent variables:  Light intensity (0%, 10%, 25%, 50%)
• Constants:  Same time (seconds), temperature (degrees Celcius), and carbon dioxide (empty bottle)
• Control:  0% light intensity

Experiment Data Table (Measured in amount of bubbles)

	0% light intensity	10% light intensity	25% light intensity	50% light intensity
Trial 1	0 bubbles	9 bubbles	13 bubbles	15 bubbles
Trial 2	0 bubbles	9 bubbles	13 bubbles	14 bubbles
Trial 3	0 bubbles	10 bubbles	13 bubbles	14 bubbles

In this lab, we asked the question, “Will light intensity affect the amount of oxygen bubbles that will be released?”  I found that the more intense the light is, the more the plants will produce oxygen bubbles.  After three trials for each light intensity, I found an average of 0 bubbles for 0% light intensity, an average of 9 bubbles for 10% light intensity, and an average of 14 bubbles for 50% light intensity.  This quantitative evidence shows that if the plants that are exposed to more intense light, then the plants will produce more oxygen to areas where there is less light.

This lab was done to demonstrate how the intensity of light would affect the amount of oxygen produced.  From this lab, I learned that the plants need to be exposed to more intense light in order to produce more oxygen.  The conclusion to this lab makes sense because in class we learned that the more of something but in, the more will come out.  Using the equation I learned in class, 6CO2 + 6H20 = C6H12O6 + 6O2, I can conclude that if we added more of one thing on the left side, the more will come out from the equation because the more of one variable you put in, the more of another thing will pop back out.  This lab helped me understand the concept of photosynthesis because I was able to manipulate one part of the photosynthesis equation and see how if affects the amount of product it will produce.  Based on this experience from this lab, if I wanted to grow my own plants in a garden, for example, I would know how to make the plants grow faster.  If I have any problems growing my plants, I could think about what I did in this lab to see how to make the plants grow at the normal rate or even faster than the normal rate.

Egg Diffusion Lab Questions

     In the Egg Diffusion Lab, we answered the question "How and why does a cell's internal environment change, as it's external environment changes?"  We then tested this by putting an egg in deionized water and another egg in corn syrup.  After letting the egg sit for one or two days, the egg was soaked in vinegar to cause the membrane to harden.  Then after another few days, the egg in deionized water increased while the egg in the corn syrup decreased in size.

     As the sugar concentration increased, the egg started to shrink in both mass and circumference.  The process on what happened on the egg is known as diffusion.  Diffusion is when there is an unequal balance of solutes to solvents so the solutes need to move in or out of the cell.  It also takes no effort which is known as passive transport.  This causes the cell to either shrink in size or increase in size because of higher concentration or lower concentration.  For example, the corn syrup had more solutes than the egg so the solutes in the corn syrup would transfer to inside the egg, changing the shape of the egg.

     The cell's internal environment changes as the external environmental changes because the cell needs to adapt to the new environment.  For example, a person would sweat if the temperature outside is getting too hot for the body to cool down.  The cell changes by making adjustments such as diffusion to maintain an equilibrium.

     This lab demonstrated diffusion because of of the eggs grew and one of the eggs shrank.  We learned that the reason why was because of diffusion.  The egg in deionized water grew because the deionized water was rushing into the egg to maintain equilibrium while the egg in the corn syrup was rushing out to maintain the concentration level of both outside and inside the egg, which is known as hypertonic solution.

     The fresh vegetables are sprinkled with water because the water causes the vegetables to diffuse because there is more concentration on one side than the other.  Also, the salt on the ice causes the ice to melt because the salt causes the ice to diffuse and maintain equilibrium, which will make the product different.  I would want to test other kinds of solutions thicker than corn syrup and less dense than the deionized water because I want to see how much more the different types of solutions would effect the egg.

Egg Macromolecule Lab Conclusion

     In this lab we asked the question "Can macromolecules be identified in an egg cell?"  Our group found that macromolecules can be found throughout the egg.  Our group found lipids in the egg membrane.  Our group found protein in egg white.  Our group found monosaccharides in the egg yolk.  During the experiment to find lipids, the amount of lipids found in the egg membrane ranked 8 on a scale from 1-10, 10 including abundant amounts of that macromolecule.  During the experiment to find protein, our group found a rank of 5 for abundance of protein.  During the experiment to find monosaccharides, our group found a rank of 7 for abundance of monosaccharides.  This data supports our claim because the macromolecules were found in the places our group thought it would be.  The lipid would be found in the cell membrane, the protein would be found in the egg white, and the monosaccharide would be found in the egg yolk.

     While our hypothesis was supported by our data, there could have been errors due to the different judgments people had when scaling the amounts of macromolecules from 1-10.  Another error could have been that the tubes did not go into the water at the exact same time.  The tubes were put in one by one and then started the timer started after the last tube entered.  Then after the timer ended, the group took out the tubes one by one and started observing.  The observation time would be different because the tubes would have time to change color more or less time than the other tubes.  Due to these errors, in future experiments I would recommend providing a color scale to base the numbers from 1-10.  The lab sheet should have a color to say that a 10 would look like this and a 1 would look like this.  For the second problem, I would recommend having a friend help put in all four tubes at once and another person starting timer exactly when the tubes would make contact with the water.  Before the timer ends, have a friend get ready to pull out the tubes exactly when the timer ends so that way the time of the tubes sitting in the water would be almost identical.

     This lab was done to demonstrate where each of the macromolecules were located inside an egg cell.  From this lab, I learned that each macromolecule is located in a certain part of the egg because the macromolecule corresponds with what the part of the egg needs to do.  This helps me understand the different concepts of how the different macromolecules would function because the macromolecules have the same function an egg does so the macromolecules would go to where the egg needs to do its function.  For example, in biology class, we learned that lipids would be found in membranes.  It is helpful to know the information, but the information tends to stick better when the information could be seen in a real example of lab such as the Egg Macromolecule Lab.  Not only did the lab help the students understand that the fact is true, the student could see why the fact is true.  Based on my experience from this lab, I could then look at a different type of cell and locate where and what kind of macromolecule would be and why.