Chicken Wing Dissection

On Thursday, October 20th we observed a chicken wing being dissected in class. We were able to identify different types of tissues and identify the organs. During class we were able to make connections on how we were similar to the wing, and how we were different. Because the wing dissection was put up on the smart board, we were clearly able to see the color, texture, and what tissue each part of the wing was connected to. The chicken wing anatomy activities also helped us to fully understand what we saw.

Diffusion lab

On Tuesday, October 11^th we conducted an in-class experiment to demonstrate the process of diffusion and osmosis and how the iodine molecules were able to go through the selectively permeable membrane to turn the corn starch purple. The purpose of this lab was to see how a cell membrane functioned, being selectively permeable and allowing certain molecules to go through it. The materials used were able to effectively show the process of diffusion and osmosis. Common predictions made were about what would happen if the baggie was permeable to certain materials. An example of one prediction made was that the iodine used would move out of the bag if it were permeable to starch. Another prediction was about what color certain solutions in the baggie and beaker would turn. During this lab, we tried to figure out which area, the baggie or beaker was hypertonic, (higher concentration) and which was hypotonic (lower concentration) We also tried to notice what substance would be the indicator, making a distinguishing change, and what substance would dilute (make less concentrated) the iodine mixture in the beaker.  One thing noticed was that after the diffusion and osmosis occurred, the solute concentrations were isotonic, or equal in solute concentrations.

This lab proved that while the iodine molecules went from a higher concentrated area in the beaker to a lower concentrated area in the baggie that the iodine proved to be the indicator, because the corn starch in the baggie turned a shade of purple when combined with the iodine, or indicator. This lab also showed that adding more water to a concentrated area such as the one in the baggie will dilute it, or make it less concentrated, turning the solution in the baggie a lighter color due to it being diluted. It also showed that the iodine moved. This was determined by the starch turning purple when in contact with iodine. We were also able to see which substances the plastic baggie was permeable to, which was iodine.

The process of diffusion and osmosis can be related to everyday occurrences. For example, the most popular process of diffusion would be with tea. When a tea bag is placed in a cup of water, the water turns a different color due to the insides of the tea bag diffusing throughout and giving it color and taste. A second example would be a helium balloon. On the first day the balloon is full of helium and floats in the air. As the days go on, the balloon slowly loses its helium and falls to the ground.  By doing this, the concentration becomes equal on both sides. One example of osmosis is putting a limp vegetable in water. Through the process of osmosis the limp vegetable is revived because the water is reentering the vegetable through the process of osmosis. Another example is leaving your hands in dishwater for a long period of time. Although the skin looks shriveled it is actually just bloated, due to osmosis. 

Diffusion Lab

Today in science class we worked on a diffusion lab. We used corn starch, water, and iodine to help us learn. The purpose of our diffusion lab was to be able to recognize the process of diffusion and osmosis.  We also discussed permeable membranes to answer why our results occurred. In class, we were able to define key terms such as diffusion, osmosis, and indicators. We recognized what role each part of our lab had to do with our finished product. Publish Post