Day 10-Evidence for Evolution

1. This image shows evidence for evolution in that Whales didn't originally come from the water, they evolved from land animals into aquatic animals gradually over time. This is a great example of how evolution helps keep species alive, as the Mesonychid knew there was food in the water, but couldn't swim. So over time, evolution gave him the ability to do so.

2. e. North America.

3. A dragonfly, bird and bat are all examples of convergent evolution. This means that they have similar features but came from different common ancestors. They also have analogous structures, which means that the features which they have in common, were also not present at the last common ancestors. For example, the dragonfly and bird both have wings which serve the same purpose, to fly, although, they came from completely different lineages.

4.In the Common Decent lab, one can see ancestry as evidence for evolution through the evolution of birds. Between the Chicken, Duck and Penguin, the Penguin is the oldest. From the penguin, who has only a thin layer of feathers, to the duck who has more, and finally to the chicken who has a thick layer of feathers. We can also see the evolution of not being able to fly to being able to fly.

5. Homology is the similar bone structure in different animals. An example of this is the humorous in a human. A similar structure of this bone can be found in a bird's wing, a horse's leg, a bat's claw or a whale's fin.  

Day 9-Fossils

Today we discussed the first few chapters of Your Inner Fish. Chapter 1 discussed how fossils are formed, and found. We learned that the older fossils are found deeper in the ground and the younger ones are closer to the surface. We also discussed how the location that fossils are found today, may not have been the same millions of years ago. The example was Tiktaalik, a transitional fossil (meaning that it was a species that was evolving, and in this case from marine animals to land animals). This fossil lived somewhere below the equator, but due to continental drifts, it is found today somewhere in northern Canada. Chapter 2 talked about homologies, which are the same bones in different animals. For example, an arm bone on a human is a homology of a wing bone for a bird. To conclude class we took a trip to the museum to see the actual model of Tiktaalik.

Day 8-Test Review

We reviewed for the test and took an all chemistry quiz. (I missed this class because I was sick.)

Day 7-Macromolecules

Today we went over macromolecules. We learned about polysaccharides which are long strands of sugar, which are both storage products and structural products. We learned that lipids are fats or oils that store energy. We learned about sucrose which plants use for circulating fuel and lactose which is found in dairy products and gives them their sweet taste. We learned about starch which is used in plants to make sugars and can also store a lot of energy in a small place. We also learned about nucleic acid structures which consist of DNA, RNA and ATP.

Day 6-Cell Membranes

Today we began class by discussing cell membranes. We learned that all living organisms have cell membranes(except for viruses). They are semi-permeable based on the size of the molecule and if it is polar or non-polar. We learned that they are made up of proteins which are also known as "gate keepers" because they are where molecules cal pass through the membrane. We also learned that osmosis occurs through these proteins because they are hyper-philic or water loving. The rest of the class consisted of a short lab quiz and our first house case.

Day 5-Graphs

We began class today reviewing how to make a scatter-plot graph, as we are going to need to do this for the Osmosis Lab report. We reviewed that every little detail counts from the title to labeling the axis.We used the rest of class to finish the Osmosis lab which we started the class before.

Day 4-Diffusion and Osmosis

Today we learned about diffusion and osmosis. We learned that diffusion is the movement of molecules from a higher concentration to a lower concentration. We then concluded that osmosis is the diffusion of water. In the osmosis of water, a higher concentration of water moves through a semi-permeable membrane (meaning that it lets some particles out, but not back in) into a lower concentration. This movement is the water trying to reach equilibrium, which is when all the water molecules have the same concentration as their surrounding molecules. We spent the rest of class working on a lab, testing what we had just learned.

Day 3-Water

Today we learned about water and all of its properties. We took a written quiz on basic chemistry and an oral quiz with a partner on water. For our oral quiz about water, my partner Alvin and I answered the question: Explain why ocean temperatures fluctuate much less than temperatures on land. The reason is because water has a higher heat capacity than air, meaning that it takes a lot more heat or a lot less heat to cause a significant change in the temperature in the water. This is because water is a liquid, and its molecules are not freely moving around, like they are in the air, which is a gas. Just a little heat will cause molecular motion in the air, but it takes a lot to cause the molecules in the water to start moving.