Photosynthesis Lab

This week in AP Biology we did a lab on plant pigments and photosynthesis. In the first part of the lab you get a piece of chromatoraphy paper and rub a spinach leaf on top of it with a quarter, so the pigment of the spinach leaf will be on the paper. You then put the tip of the chromatography paper into an alcoholic solvent, so the pigments will travel up the paper. When the pigments are completely done traveling up the paper, you measure where each pigment ends ( carotene, chlorophyll a, chlorophyll b) and  you calculate Rf values by dividing the pigment with the solvent. In the second part of the lab you get a spinach leaf and use a hole puncher to punch holes in the leaf to make leaf discs. After that you put the leaf discs in a syringe. Once the leaf discs are in the syringe, you fill the syringe up with. When the leaf discs are in the syringe with the solution make sure to make the leafs sink to the bottom by vacuuming the air out. Once the leafs are sunk, you then put the leaf discs into a solution which is mixed with water and baking soda (which gives off carbon dioxide) and you put the the leaf discs under a light source and calculate how many float to the top every 30 seconds.

Photosynthesis

This week in AP Biology we discussed about photosynthesis. Photosynthesis is the process where plants use sunlight to synthesis their food from carbon dioxide and water. I have been taught photosynthesis since elementary, but I never knew how complicated and complex it really was until we started learning about it in depth. Photosynthesis occurs in the chloroplast of the plant.There are two parts to photosynthesis, and they are the light reaction and the Calvin Cycle (also known as the dark reaction) . The light reaction occurs in the thylakoid membrane and it converts light energy to make chemical energy. The light that is absorbed is used to make ATP and also produces NADPH. The Calvin Cycle uses ATP as an energy source and also consumes NADPH so it can add high energy electrons to make glucose (sugar). There are three phases in the Calving Cycle. The first phase is called Carbon Fixation which is when carbon dioxide is made into a five carbon sugar called ribulose biphosphate or RuBP. The second phase is Reduction which is when ATP and NADPH are used to convert 3 phosphoglycerate to glyceraldehyde 3 phosphate which is the predecessor to glucose and other sugars. And finally the third phase is Regeneration. Regeneration is when even more ATP is used to convert glyceraldehyde 3 phosphate back to RuBP (which is the acceptor for carbon dioxide) so the cycle is complete. For the Calvin Cycle to continue this, the light reaction must continue regenerating ATP and NADPH. Without photosynthesis, anything that needs oxygen to survive will not be alive without it. Photosynthesis is one of the most important processes to occur.

Successful Blog

This week in AP Biology we redid our lab, and this time it was a success. To prevent the vials from getting water leaked into it, we used super glue instead of petroleum jelly which is what we used at first and that is how the lab failed last week. The purpose of the lab is to get germinated and nongerminated peas and put them in 6 vials with a cotton ball soaked in KOH. The vials 1-3 are placed in a room temperature bath and vials 4-6 are placed in a chilled waterbath. After that is done, you then place the 6 respirometers on each vial and place them in their designated waterbath. With the vials successfully done, we could now get the data we needed. This data was to show the relationship of gas laws to the function of a respirometer and the effect of temperature and germination or nongermination on cell respiration. The germinating peas consumed the most oxygen in both the room temperature waterbath and the chilled waterbath because it performs cellular respiration while the others do not. The lab seems fairly simple, but it is a very tedious process. 

Unsuccessful Week

This week in AP Biology, our class attempted to do a lab about cellular respiration. There are previous blogs that  explains cellular respiration and the steps that occur. This lab turned out to be a complete fail. I was not able to see the start of the lab because of an extracurricular activity, so I can't really explain the whole process, but the purpose of the lab is to demonstrate the relationship of gas laws, the effect of temperature and germination or nongermination on cell respiration, and the relationship between dependent and independent values. Like I said, I was not in class during the start of the lab, so I will not know as much or be able to explain it very well. However, the purpose of the lab is to get germinated and nongerminated peas and put them in 6 vials which has a cotton soaked with KOH. 1-3 is placed in a room temperature bath and 4-6 is placed in a chilled waterbath. After that, you place 6 respirometers  in the waterbaths, but our respirometers got water leaked inside, so it ruined the lab. If the respirometers did not get water inside, then we would have to record the volume.

3 Steps Of Cellular Respiration

This week in AP Biology we continued discussing cellular respiration once again. Since we have a quiz this week, we just reviewed about cellular respiration and the three steps of cellular respiration. These three steps are glycolysis, Kreb's Cycle ( citric acid cycle) and Electron Transport Chain (ETC). Each step works differently, but they each produce energy in the form of ATP. Glycolysis occurs outside the mitochindria and it breaks down glucose into two molecules called a pyruvate and also produces 2 ATP's and 2 NADH molecules.  The Kreb;s Cycle, which is also known as the citric acid cycle. The Kreb;s cycle occurs in the mitochondria where the pyruvates are transported and loses carbon dioxide to form acetyl CoA and later makes 2 ATP's, NADH and FADH. And finally ETC (also known as Oxidative Phosphorylation) also occurs in the mitochondria and it releases a large amount of chemical energy to produce about 34 ATP's. These are the three steps of cellular respiration.

Cellular Respiration

This week in AP Biology we talked about cellular respiration. Cellular respiration is the metabolic process whereby certain organisms obtain energy from organic molecules. Without cellular respiration, no organism would be able to acquire energy. Another thing we discussed in class was aerobic and anaerobic respiration. Aerobic uses oxygen while anaerobic does not use oxygen. Also anaerobic produces lactic acid while aerobic does not. Lactic acid is produced in the muscle tissues during an intense exercise. That is why when someone gets done with a difficult workout they pant for oxygen because your body is getting all of the lactic acid out and taking oxygen in. There are three steps in cellular respiration, and they are glycolisis, Kreb's cycle, and Electron Transport Chain (ETC). Each one of these steps build up on each other to make several ATP's. (I don't know the cycle very well enough as of now to explain it very thoroughly). Cellular respiration is very important to any organism because we need energy to make our body work properly.

Gibbs Free Enegy

This week in AP Biology we talked about Gibbs Free Energy. Gibbs Free Energy is a bit confusing, but after a while you start getting the hang of it (I don't know it well enough to explain it very well). Free Energy is very important in the universe. Without Free Energy, then nothing would be the same and our body wouldn't be able to function as quickly as it does now. Another thing we talked about in class is enzymes. Enzymes are simply proteins that speed up reactions. If we didn't have enzymes then it would take years and years and years to even digest the simplest things. Another thing we talked about is metabolism. A metabolism is the chemical processes that occur within a living organism in order to maintain life. Without any of these things, our body would not be able to function as well as it does now.



 

Osmosis & Diffusion

This week in AP Biology we didn't really discuss about much because of a lab we are doing in class(which we still haven't completed), so we pretty much reviewed what we learned last week. But most parts in the lab is about osmosis and diffusion, which is something we talked about last week. Osmosis is the movement of water in a cell and diffusion is the movement between other materials in a cell. Without osmosis or diffusion, our body would not be able to transport all of the nutrients from the food we eat and drink.Both osmosis and diffusion have similarities and differences. For example diffusion occurs in a gaseous state while osmosis does not and diffusion moves from high to low and osmosis is vice versa. Like I said, we didn't discuss about a whole this week because of an important lab, but either way it was still interesting to talk about osmosis and diffusion in detail again.

Plasma Membrane

 This week in AP Biology, we talked about the plasma membrane, what its job is,things that happen within the membrane, and the parts of the membrane. The plasma membrane is composed up of a phosolipid bi-layer and it is the boundary of a cells between life and non life. It is also amphipathic, which means that it is both hydrophilic and hydrophobic. We also talked about endocytosis and exocytosis. Endocytosis is when materials move into the cell and exocytosis is when materials are moved out of the cell. Another thing we discussed in class was diffusion and osmosis. Diffusion is just transporting materials into the cell and osmosis is transporting water into the cell. Also Also another thing that deals with osmosis is hypertonic, hypotonic, and isotonic solutions. Which just means the amount of water and the amount of concentration. Hypotonic is when there is more solute than solvent, hypertonic is when there is more solvent then solute, and isotonic is when they are both equal. As you can see we discussed about several things this week and it was all really interesting.




Plasma Membrane:



Hypertonic, Hypotonic, Isotonic:

Prokaryotes VS Eukaryotes

This week in AP Biology we didn't really learn anything new. We simply just reviewed over the cell for our quiz. We talked about the differences between a eukaryote and a prokaryote and also what they either share in common or what they lack in common. The most obvious reason is that prokaryotes do not have a nucleus and eurakyotes do. Another differences is that prokaryotes are obviously smaller and they also have a different structure. The only two things they have in common is that they both have vesicles and vacuoles. Bacteria and Archea are prokaryotes because they do not have a nucleus and eurakyotes are animals and plants because they do have a nucleus. Scientist believe that some prokaryotes were ingested by eukaryotes. The evidence they have is that the mitochondria was once a prokaryote and it is now present in a eukaryote. Like I said before, we did not really talk about anything new because we were mainly focusing on reviewing for our quiz. To show you more differences between prokaryotes and eukaryotes, here is a picture to show you:

Animal Behavior

This week in AP Biology we talked about animal behavior. Animal behavior is simply the scientific study of an animal's behavior. Every animal does something unique to figure out situations and to of course survive. The two main types of animal behavior is innate behavior and learned behavior. Innate behavior is something you know from day one and learned behavior is obviously something that you learn how to do, such as teaching your pet dog tricks. Other examples of animal behavior is instinct, fixed action pattern, imprinting, associative learning, trail and error, habituation, observational learning, and insight. Each one of these examples are completely different. Instinct is something an animal has on day one and does automatically. fixed action pattern is a series of patterns until complete. Trail and error is when an animal taught something and goes through trial and error ( hence the name) until they eventually catch on. Insight is when an animal is given a problem and they have to figure it out also some animals don't have insight, so they will not be able to figure situations. An animal that does have an insight is a chimpanzee. An example of a situation is when you put a chimpanzee in a room with a few boxes and a banana tied to the ceiling, the chimpanzee would eventually figure it out. Animal behavior is a very interesting thing because of the many different examples and animal can have. We started on a animal behavior lab about pill bugs in different environments and so far it has been really fun and interesting.

What I Have Learned So Far.....

On the first day of school, there were about 15 students in our AP Biology class, but before we started anything several students dropped the class. Now there are 9 left. I didn't no what to expect in this class, but I do know that it is not going to be easy..... The first thing we started talking about was water and its properties and the chemical context of life. Both were very interesting because I learned some things that I have learned before, but more in depth then in my previous science classes. For example polar, non polar, covalent and ionic bonds I now know way more about than I ever had. After that our class took a quiz over water and the context of life, which made me extremely nervous, but I passed. After the quiz, we talked about the importance of carbon and macromolecules. Now I learned something completely new.I learned about the chemical groups, hydroxyl, carbonyl, carboxyl, amino ,sulfhydryl, phospahte and methyl. We also talked about hydrolysis and dehaydration reaction, which is when water is either taken out or put into an enzyme.


         Even though I have been in this class for a few weeks, I have learned about several things that I haven't heard about before or learned more about a subject then I have before.