Is sex important?

In the chapter Wholly Virgin from the book Dr. Tatiana's Sex Advice to All Creation, the Philodina and the narrator discussed about whether sex or asexual reproduction was more efficient and why. I think that sex is important because as it said in this chapter, "...sex may be an advantage is because the shuffling of genes gives an edge in the perennial battle against disease."(228) Also we can adapt to our environment because gradually organisms would need to change to be able to survive. One of the costs of reproducing sexually is that females need to have more than two children in order for the population to stay the same or grow, when asexual reproduction needs only one child for the population to stay the same. But the costs of reproducing asexually is that the organisms genes don't change and they stay the same which can be bad because they wouldn't be able to survive if their environment changed. Some arguments in the chapter were, "...what is sex for..."(213). Another one was, "Or, to get back to the central question, if they can do without sex, why can't the rest of us?"(216) The next one was, "In the long run we're all going extinct," said Miss Philodina tartly. "Sex won't save you from extinction! The dinosaurs had rampant sex, and look what happened to them. You can have sex till you're blue in the face, but if your habitat vanishes, it's you and the dodo."(224) Finally another one was, "The pocket mouse bravely interrupted: "But surely if you don't have sex, you can't adapt to the future? If you can't adapt to the future, you haven't got a future."(224) A question I have is, which organisms be both asexual and sexual?

Unit 3 Reflection

Egg Diffusion Lab

This unit was about the types of cells such as prokaryotes which have no nuclei, and eukaryotes which have a nucleus and an example are plant and animal cells. We also learned about where macromolecules are located in cells and what their purpose is. We learned about how membranes are semi-permeable which means that some molecules can cross the membrane and others can't and how molecules travel in and out of cells by diffusion, facilitated diffusion, and passive and active transport. Later we learned more about diffusion and osmosis which is the diffusion of water across a semi-permeable membrane. We learned about hypotonic, isotonic, and hypertonic solutions which we tested in our egg diffusion lab where we put eggs in different solutions such as corn syrup and deionized water. Towards the end of the unit, we learned more about cells and the organelles in a cell and their purpose, and autotrophs that make their own food and heterotrophs which consume other organisms for food. At the end of the unit we learned about photosynthesis where plants produce glucose and oxygen using sunlight and carbon dioxide, and cellular respiration which is the process of cell breaking down glucose into energy.

Egg Macromolecule Lab

My weakness during this unit was understanding the process of photosynthesis and the steps of cellular respiration. My strengths were when we learned about cells because I was taught about cells before at school. I learned more about what the organelles contribute to in cells and photosynthesis. I now know about what osmosis and diffusion are better and what cellular respiration is and what ATP is. I am a better student than I was before, because when we started this unit I had no clue what we were learning about and know I know more things after we had to do things during class and watching the vodcasts.

Egg Diffusion Lab

In this lab, we had one group test an egg in deionized water and the other group tested an egg in sugar water(corn syrup) after we dissolved the egg shells. Then we observed the eggs the next class to see whether the eggs circumference or mass changed. From our results, we found out that the egg in corn syrup was in an hypertonic solution which is when the solute concentration is greater than the inside of the cell and the cell loses water so the cell shrinks and the corn syrup could've had a higher solute concentration than water.

When we looked at the class data, the mass and the circumference decreased when the sugar concentration increased. There was probably more solute concentration outside the cell which made the egg shrink. The egg that my group tested decreased by over forty grams in mass and four centimeters in circumference, which shows that the egg lost a lot of its water from its cells.

The cell's internal environmental changes when molecules go in and out of cells and it can change through osmosis, which is the diffusion of water across a permeable membrane, and also passive diffusion where there is no energy exerted and it moves from high to low concentration.

This lab demonstrates how diffusion and osmosis works by using eggs as the cell. We also found out whether the egg was hypotonic, hypertonic, or isotonic.

Fresh vegetables are sprinkled with water, because if the cells in the plants don't get a lot of water, then the cell would start to lose water which would make the cell shrink. Roads are probably salted to melt ice, because salt has a higher solute concentration, so it make the cell lose its water which makes it shrink.

I would like to test to see what solutions would make egg hypertonic, hypotonic, or isotonic, because in this lab we only found out that corn syrup makes it hypertonic, and deionized water makes it isotonic because it stayed the same shape.

Egg Macromolecule Lab

In this lab we asked the question, Can macromolecules be identified in an egg cell? We found that that egg membrane tested positive for proteins, because the membrane in the solution became purple. Also, proteins can be found in the cell membrane because it allows the transportation of molecules that go in and out of the cells. This data supports our claim because it shows why the membrane was tested positive when added with the solution sodium hydroxide.

We found out that egg white tested positive for proteins when we added sodium hydroxide to it. Proteins are found throughout the cell, and there are enzymes and proteins in the cytoplasm. This data supports our claim, because it shows why there are proteins in egg whites.

Finally, we had nothing that tested positive for egg yolks.

Our data was unexpected, because nothing tested positive for egg yolk and lipids didn't test positive for egg membranes, which could have been due to the amount of drops added to the egg parts and the time the solutions were added and how long the solution was in with the parts. These errors could have affected the results, because it could've changed why we didn't get results that we should've and changed the outcome of our data. The amount of drops added could've affected the results, because if too little was added to the egg parts, then you wouldn't be able to tell if the part reacted to the solution. The time could've affected it too because if a person decided that none of them were changing, they could've just assumed that even though it was going to react after a little more time. Due to these errors, in future experiments I would recommend to have people read the instructions more carefully, especially when having to do exact measurements of liquids. Also, I think that we shouldn't rush through things and just take our time so that we could focus on the labs more.

This lab was done to demonstrate the four macromolecules that we learned in one of our vodcasts. From this lab I learned how to find out what macromolecules are in certain parts of eggs and why they are present in certain macromolecules by conducting experiments which helped me understand the concept of where macromolecules are present and their purpose. Based on my experience from this lab, I now know how to tell and test to see if any macromolecules are present and I know what macromolecules are present in certain parts of eggs.