Tuesday, October 30, 2007
Tues-Day 1
Bio- we reviewed the various types of asexual reproduction. We then applied our knowledge of what occurs during the various phases of mitosis and interphase to an on-line quiz that showed slides of cells in various stages of cell division. We also focused on the "diploid" chromosome number; diploid means that there are two of each type (size, traits coded for) of chromosome. For example, human body cells (all human cells except for sperm cells and egg cells) have a diploid number of 46; that is 23 PAIRS of chromosomes totalling 46 separate chromosomes. Mathematically, this diploid number is written as 2n. So, for humans, 2n = 46.
We saw that, for whitefish, 2n = 18 because each whitefish cell has 18 separate chromosomes or 9 PAIRS of chromosomes.
Here is the link to that website.
Here is a link to a good pictorial site on Mitosis
Chem 7- we reviewed some of the graphs that represent the gas laws.
We then focused on Dalton's Laws of Partial Pressures. These two inter-related laws are as follows:
The total pressure of a mixture of gases must be equal to the sum of the partial pressures of the gases in the mixture. That is pretty much an obvious statement but it is essential in understanding the next law: the partial pressure of each gas equals its "mole fraction" times the total pressure. The "mole fraction" of gas "A" represents the fraction of all of the collisions of the gas particles that are due to gas A. Thus, if half of the gas molecules in a mixture of gases are gas A molecules, then gas A molecules cause half of the collisions that are occurring at any given time in that container. Therefore, gas A causes/accounts for half of the pressure in that mixture.
We then did several examples and permutations of Dalton's Law problems.
Chem 8/9- we completed each of the graphs representing the various gas laws: Boyle's, Charles's, Gay-Lussac's, and Avogadro's. We saw that ONLY Boyle's Law shows an INVERSE relationship (HYPERBOLA) between the variables, which are pressure and volume (given unchanging temperature and "moles"/number of gas molecules. All of the other laws show a directly proportional (LINEAR) relationship, that is, as one variable increases, the other variable increases.
We then did a lab that showed one of the gas laws can be applied in order to crush a can just by condensing the water vapor inside the can. You'll receive the handout for that lab tomorrow but I'll post a copy on Blackboard anyway.
We saw that, for whitefish, 2n = 18 because each whitefish cell has 18 separate chromosomes or 9 PAIRS of chromosomes.
Here is the link to that website.
Here is a link to a good pictorial site on Mitosis
Chem 7- we reviewed some of the graphs that represent the gas laws.
We then focused on Dalton's Laws of Partial Pressures. These two inter-related laws are as follows:
The total pressure of a mixture of gases must be equal to the sum of the partial pressures of the gases in the mixture. That is pretty much an obvious statement but it is essential in understanding the next law: the partial pressure of each gas equals its "mole fraction" times the total pressure. The "mole fraction" of gas "A" represents the fraction of all of the collisions of the gas particles that are due to gas A. Thus, if half of the gas molecules in a mixture of gases are gas A molecules, then gas A molecules cause half of the collisions that are occurring at any given time in that container. Therefore, gas A causes/accounts for half of the pressure in that mixture.
We then did several examples and permutations of Dalton's Law problems.
Chem 8/9- we completed each of the graphs representing the various gas laws: Boyle's, Charles's, Gay-Lussac's, and Avogadro's. We saw that ONLY Boyle's Law shows an INVERSE relationship (HYPERBOLA) between the variables, which are pressure and volume (given unchanging temperature and "moles"/number of gas molecules. All of the other laws show a directly proportional (LINEAR) relationship, that is, as one variable increases, the other variable increases.
We then did a lab that showed one of the gas laws can be applied in order to crush a can just by condensing the water vapor inside the can. You'll receive the handout for that lab tomorrow but I'll post a copy on Blackboard anyway.
# posted by C @ 7:33 AM 
