Sexual vs. Asexual Benifits

Is sexual reproduction important?

     Sexual reproduction is necessary for life. "[Sex] prevents parasites from becoming too well adapted to their hosts" (Judson 228). Sexual reproductions remove harmful mutations from the population. Sexual reproduction has a slower production rate. "Sex is an advantage because it breaks up gene combinations" (Judson 229).
     Asexual reproduction does not require fertilization, but there is very little variation, which can cause extinction. "...mammals clone once in a while, when an embryo splits early in development" (Judson 215).
     Some animals reproduce sexually and asexually. "Armadillos... engage in both sexual and asexual reproduction"(Judson 229).
     I learned that many species reproduce in different ways. Some reproduce more than others, and some reproduce sexually, while others reproduce asexually. I understood the text and all my questions were answered in the text.

Unit 3 Reflection

     Unit 3 was about cells and their functions. Macromolecules serve as the building blocks for life because they make up different parts of the cell and they all serve different purposes. The cell theory states that all things are composed of cells, a cell is the basic unit of life, and new cells generate from existing cells. Prokaryotic cells have no nucleus, while eukaryotic cells have a nucleus.

     Membranes and their unique characteristics are so essential for life because they all have different functions that are necessary for life. The nuclear membrane holds DNA in the nucleus and allows RNA to leave through the pores. The lysosome holds enzymes for recycling proteins. The endoplasmic reticulum (ER) holds proteins as they are finished off and holds lipids as they are made. The vesicles export molecules in and out of the cell. The golgi apparatus packages and releases finished proteins, lipids, and hormones. The membranes in chloroplasts and mitochondria creates carbohydrates through the process of photosynthesis, and breaks down carbohydrates through the process of cellular respiration. The cell membrane holds all cell contents inside and protects from the outside environment. The cell membrane also controls the passage of molecules inside.

       Semipermeable membranes allow some molecules to cross the membrane, while others can not. Passive transports require no effort or energy. Active transports use energy to bring rare but highly needed molecules into the cell. Diffusion is the movement of small molecules from high to low concentration through the lipid bilayer. Proteins that make it possible for large molecules to pass through the membrane through the process of facilitated diffusion. Osmosis is the diffusion of water across selectively permeable membrane. An isotonic solution is when the solute concentration is the same outside and inside the cell. A hypertonic solution is a solute concentration that is greater than that inside the cell. A hypotonic solution is a solute concentration that is less than that inside the cell.
     Cells specialize in making proteins. Mitosis is the process in which one cell reproduces by dividing into two cells. Photosynthesis converts light into chemical energy. A cell creates energy by creating ATP  from glucose to power the cell. The endosymbiotic theory explains how a large cell ingested bacteria and became part of it.
     Photosynthesis is the process in which plants produce glucose and oxygen using sunlight and carbon dioxide. Light dependent reactions occur in the thylakoids of grana. Light independent reactions occur in the stroma.
     Cellular respiration is the process of breaking down glucose into energy. It has 3 stages: glycolysis, krebs cycle, and the electron transport chain. Glycolysis produces two ATP for every one glucose molecule. The Krebs Cycle coverts molecules from glycolysis into two ATP, CO2, Nadh, and FADH2. The electron transport chain uses oxygen, NADH, Fadh2, and converts ATP into ADP. This last stage produces 32 ATP.
     The process of photosynthesis and the process of cellular respiration undo each other. Photosynthesis occurs in the chloroplasts in autotrophs, while cellular respiration occurs in the mitochondria in autotrophs and heterotrophs.
     Overalll, I really enjoyed this unit. I liked learning about photosynthesis and cellular respiration. I had a tough time remembering the function of each organelle in a  cell. I had a fun time looking at cells under a microscope, and I realized how complicated a single cell can be. 

Photosynthesis Virtual Labs

Lab 1: Glencoe Photosynthesis Lab

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 the color in the visible spectrum is blue or red, then the plant will grow bigger.

If the color in the visible spectrum is green, then the plant will grow the smallest.

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 planting spinach in all the different lights for 30 days. Then I did the same for the radish and lettuce.In my experiment, the controlled variable was the type of plant. The variable that I changed to compare the growth was the color of the light.

Results:

Filter Color	Spinach Avg. Height (cm)	Radish Avg. Height (cm)	Lettuce Avg. Height (cm)
Red	18	12	12
Orange	16	7	5
Green	3	2	3
Blue	18	15	12
Violet	15	11	7

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.

My data supported my hypothesis. I predicted that the blue light and the red light would show the most plant growth and that green light would show the least amount of plant growth. I found that spinach grew best under the red light and the blue light. The radishes showed the second most amount of plant growth under red and blue light. The lettuce showed the least amount of plant growth under red and blue light compared to the spinach and the radish.

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

I conclude that blue light causes the most plant growth in the visible spectrum.

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

I would expect a normal rate of growth under white light because white light is an average of all light lengths.

Microscope Lab

Microscope Lab

Power: 400x

The amoeba is unique because it has pesudopods, whcih surround food and pull the food into the cytoplasm.

The amoeba has purple and blue pesudopods.

It is a eukaryotic cell, and it is heterotrophic. 

Power: 400x

The euglena is unique because there are dark circles inside the cell.

The euglena is green because it has chloroplasts.

It is a eukaryotic cell, and it is heterotrophic and autotrophic. 

Power: 400x

The cyanobacteria has no chloroplasts because it has no green pigments.

The cyanobacteria looks like blue links of sausage.

It is a prokaryotic cell, and it is autotrophic. 

Power: 400x

The bacteria cells is unique because it consits of cocci, bacilli, and spirillums.

The bacteria cell has many visible spirllum, which looks like a spiral twist.

It is a prokaryotic cell, and it is autotrophic. 

Power: 400x

The spirogyra is unique because it has visible spirals.

The spirogyra is green because it has chloroplasts.

It is a eukaryotic cell, and it is autotrophic. 

Power: 100x

The ligustrum is unique because it has long cells.

The ligustrum is green because it has chloroplasts.

It is a prokaryotic cell, and it is autotrophic. 

Power: 400x

The skeletal muscle tissue is unique because it has many nuclei.

This animal cell looks like blocks and strings.

It is a eukaryotic cell, and it is heterotrophic.

Egg Diffusion Lab

Egg Diffusion Lab

     In this lab, we asked the question: how and why does a cell's internal environment change, as it's external environment changes? We placed the egg in vinegar for 48 hours to dissolve the outer shell, to make the membrane visible. Then, we measured the circumference of the egg and the mass. After, we put one egg in water, and the other in corn syrup. The corn syrup egg had a 44% decrease in mass, and the circumference had a 26.16% decrease. There was a significant decrease because the water solvent and the sugar solute made the egg diffuse into a high concentration.
     A cell's internal environment changes as it's external environment changes. This change is due to one of the theories of life, homeostasis. Homeostasis is the tendency towards maintaining a stable equilibrium. Passive diffusion changes the internal environment of the cell. Low concentration outside the cell, and high concentration inside the cell is a hypertonic solution.
    This lab demonstrates the biological principle of diffusion. The egg loses water when it is surrounded in corn syrup because it is a hypertonic solution. The egg gets filled with water through the process of diffusion because it is a hypotonic solution.
     Sprinkling fresh vegetables at markets with water keeps them firm and hydrated so they appear fresh and good looking for the buyer. Since water is hypotonic to vegetables, water has fewer solutes and a higher concentration of water than inside the vegetable cells. This makes more water diffuse into the vegetable cells than the amount of water that difuses out of the vegetable cells. More water inside the cells makes the vegetables firm. Roads are salted to melt ice because salt lowers the freezing point of water. Lowering the freezing point makes it possible to take advantage of a lower melting point. As the water and salt dissolves on the road, it forms a salt solution.  Outside of plant cells, this is a hypertonic solution. The hypertonic solution causes the water in the plant cell's cytoplasm to move out of the cell through the process of osmosis. The inside of the cell becomes dehydrated, making the cell and the plant die.
     Based on this experiment, I would like to test a different substance, other than an egg, to see if the substance has the same affect on hypertonic and hyoptonic solutions. I would like to see if the substance also expands when it is placed in water, and if it shrinks when it is placed in sugar water.

Egg Macromolecules Lab

Egg Macromolecules Lab

     In this lab, we asked the question can macromolecules be identified in an egg cell? In the egg membrane, when a mixture of sodium hydroxide (NaOH) and copper sulfate (CuSO4) was added, the solution tested positive for proteins. The membrane changed to a lavender color. It scored a 5 out of 10 points on a scale of amount of color change. This happened because there are transport proteins in the egg membrane that keep bacteria out. The egg white tested positive for proteins when a mixture of sodium hydroxide (NaOH) and copper sulfate (CuSO4) was added. The egg white turned dark purple, and earned a 7/10 on the color changing scale. The egg white tested positive for proteins because there are structural proteins used as food, and enzymes in the immune system break up bacteria. The egg yolk tested positive for lipids. The yolk changed to a medium red color and earned a 7 out of 10 on the color changing scale. Lipids can be found in the egg yolk because lipids store energy and sugars in the egg yolk.
    While our hypothesis supported was supported by our data, there could have been errors due to the egg yolk not mixing in with the solution. Due to these errors, in my future experiments I would recommend making sure the solution mixes before testing my hypothesis. I would also recommend using a pipette to mix the solution.
     This lab was done to demonstrate where macromolecules are found in a cell. From this lab, I learned where monosaccharides, polysaccharides, proteins, and lipids can be found in an egg, which helps give me a hands on activity showing where macromolecules can be found in a cell. It also helps me understand the structure of a cell. Based on my experience from this lab, I can find each of the macromolecules in a cell and I understand how important it is to consume every type of macromolecule.