Blog for 1/29/10

Dear Marika

The difference between mitosis and meiosis is that meiosis makes sperm cells and egg cells. Mitosis creates normal cells, like skin cells and cheek cells. They are non-sex related cells. In mitosis, you make only 2 cells, when meiosis makes 4. They all have different chromosomes. They have one kind from mom, and another from dad.

Blog for 1/25

This week, we started meiosis. Meiosis is very close to mitosos, but is very diffrent in many ways. In meiosis, you create sperm cells or egg cells. Also, the DNA in each cell meiosis makes is diffrent. The ending number of cells in meiosis is 4, unlike mitosis which ends up with only 2. Each cell made during meiosis has half the number of chromosomes as cells made during mitosis. That is because sperm cells would connect with another cell with half the number of chromosomes, from the female, and together, that would make 100% chromosomes. Mitosis creates 2 exactly the same cells. Mitosis create cells for the reason of just division, not anything to do with sex.

Blog for 1/19/10

This week, I learned a lot about mitosis and the different steps of it. A step before mitosis even begins is interphase. This phase is when the cell is normal and the DNA is still spread out. When did an activity online with the whole class, we summarized that in a whole cell, most of the cells are in the process of interphase. As an experiment, we looked at onion ring cells which had been preserved to look just as they had when they were alive. When we looked at these cells under a microscope in high power, you could see the DNA, and tell which phase it was probably in. The ones with only 1 small dot meant that the cell was in the phase of interphase. The ones with many small squiggles and looked as though they didn't want to be separated were in the phase of metaphase. We also learned about the differences between chromatids, chromosomes, and chromatin. Chromatid is the unraveled DNA. A chromosome is a single strand of a chromatin. A chromatin is in the shape of an X and is connected with a small thing called a kineticore.

Blog for 12/14

The steps for protein synthesis are:

1. The cell gets a message to make a certain kind of protein.

2. A part of the DNA unwinds, showing the gene responsible for the protein

3. With the help of enzymes, the nucleotides move one strand of the exposed gene and make a m-RNA

molecule

4. Many copies of m-RNA are made according to the amount ordered; they leave the nucleus through

the nuclear pores in to the cytoplasm.

5. An m-RNA connects with a ribosome so that the m-RNA could be decoded; the message is read a

codon at a time.

the steps for photosynthesis

This week, I learned about the respiration system that takes place in a plant cell. An organelle called mitochondria is where the respiration takes place. It takes in C6 H12 O6 and O2 and gives out CO2 and energy. The energy that they give put comes from the sun. There was also something called fermantation. Fermantation is respiration without oxygen, and in that case, the body makes alcohol, and also lactic acid. When the body creates the acid, you get a cramp. I also learned about the steps of photosynthesis. An organelle called chloroplast is where photosynthesis takes place. Chloroplast has the green color that makes the whole plant green. The photosynthesis equation is CO2+H2O+ energy----------C6, H12, O6+O2.

This week, I learned about the way humans breath. More specifically, we learned about what we breathed in and breathed out. Our class came to a conclusion that we breathed in oxygen and breathed out carbon dioxide. We tested this by breathing into jars with a gas sensor on it, and if the number on the sensor got larger when we breathed in to the jar, that meant that we breathed in oxygen. If the number on the sensor got smaller on the sensor after you inhaled into the jar , that meant that you breathed out carbon dioxide. By doing some research, we figured out that we breathed in O2( oxygen) along with C6, H12, and O6, which all together and combined create carbohydrates, or food/energy. I also learned about the different combinations of atoms which create different molecules of air, like 1 carbon and 2 oxygens create CO2, or carbon dioxide. 2 oxygens create an oxygen molecule. Another thing that I learned was about photosynthesis. This is the process in which plants use the energy that they collect from the sun to convert it into sugar, which they use as food.

This week, we did not learn much because it was a 3-day week. On Monday, we researched the insides of animal cells and plant cells. These insides of cells are called organelles. There was a nucleus in each cell, and mitochondria as well. In the plant cell, there was something called chloroplast which maintained the green color of the plant. The organelles in the animal cell were all mostly in the plant cell as well. On Tuesday, we talked about the organelles in the plant cell and animal cell and researched the functions of all the organelles. Some of them were that the nucleus controlled almost everything about the cell, like the cell's actions. The cytoplasm keeps everything in place inside the cell. The cytoplasm is like some kind of gel which fill the empty spaces in the cell. On Wednesday, we talked about paramecium which we had to research for homework. Paramecium was shaped like a foot, and was sometimes called the lady slippers. We thought about the places where paramecium could be found, and thought about where most bacteria was found: still water like ponds and swamps. We got a sample of still water full of duckweed, a kind of aquatic plant. Under the microscope, there were many things that looked like paramecium.