Day 11: Evolution and DNA Lab

Here are my answers to the Quiz

Block: B

Honors Biology

Evidence of Evolution Quiz

1. Explain the following picture in terms evidence for evolution.
This is an example of the fossil record and how species can show the transition and developments in evolution. This is usually a gradual change and many species evolving from each other that have been discovered in fossils can show this. If there is a missing link, however in the fossil line up has what seems to be a rapid change. The dog- like creature in this picture is shown how slowly he evolved into a whale from many different forms.

2. Which of the following continents did marsupials begin from?

The answer is E) North America.

3. Comparing a dragonfly, bird, bats - explain the type of evolution that these organisms show.
These organisms display convergent evolution. Convergent evolution is when two organisms developed similar traits and analogous structures and had a very distant ancestor with each other. They all are analogous-related species meaning that the internal structure of their bones are different but they developed the same ability in the function of those bones. This is apparent in bats and birds because their wing bones are quite different but they still have a process in flight. There are the different bone structures in number 2 and number 3 cleearly.

4. Explain how the Common Descent Lab shows DNA evidence and ancestry as

evidence for evolution. Include examples of Primates.

The Common Descent Lab showed specific DNA evidence because we ordered the sequences of the DNA exactly like it is in a gorilla, chimpanzee and a human and compared them. Our DNA sequences matches very closely to the chimp's DNA sequence showing that we are more closely related. For example we have 15 DNA sequence matches with a chimpanzee and 10 with a gorilla. Which means we are further related to a gorilla than a chimp. The gorilla is closer to the common ancestor because it has more matches in the DNA sequence to the ancestor's DNA.

5. Explain homology using some examples from your readings.

Homology is when the internal structure of the bones in different species are similar showing that we all evolved from a common ancestor. Some examples of this is the Tiktaalik fossil that Shubin found. Examining the arm of this fossil, we can see that the arm has the same pattern of bones that we do 1 bone to 2 bones to lots of tiny bones in the hand. They may have been different in functioning, but the internal structure is the same.

Day 10: Evolution a New Unit!

We learned about the fossil record and how fossils are made today. We discussed our homework which was to read some chapters out of Your Inner Fish which is about evolution and how the early life forms of fish progressed to being land animals, which eventually evolved to be humans.

This is a picture of the Fossil that the author Neil Shubin found in the Arctic:

This is a transitional fossil discovery. Previously to the discovery of this fossil there was discoveries of ancient fish and a discovery of a type of first reptile called Hynerpeton.

They looked for the fossils in the Arctic and Ellesmere island because of geological research and the historic continental drift showing that the tropical equator continent from 375 million years ago moved north over time. They wanted to explore an unknown region and didn't go looking in the very surveyed east region of Greenland.

The evidence found of evolution in this fossil was immense:

• In the arms of this fish it showed the transition from ray bones in a fish to the formula us humans and other mammals have which is one bone- two bones and lots of phalanges in the front. 
• The Tiktaalik had eyes on the top of his flat head unlike fish to better see with, when not always submerged. 
• The Tiktaalik's ability to push itself up is due to the movement thru the probably rough terrain and escape from predators thus developing an important factor of natural selection and evolution.

Day 9: We took a test.

We had to answer a free response on potatoes and how diffusion affects them.
Then a multiple choice section on the rest of the unit.

Day 8: Review, Quiz and Fire

Today we reviewed all the material we covered over the past few weeks.

We reviewed basic chemistry, water, and organic compounds.

We then took a quiz. The basic chemistry part covered electron configuration and the differences between a covalent bond and polar bonds. The water part covered the bonding of hydrogen and how that effects the properties of water. Then the organic compounds covered what the differences between a carb, a lipid, a protein, and nucleic acid is and how their structural isomers are.

Then there was a fire and so we had to finish class.

Day 7: Who took Jeryll's ipod?

Today we did a lab about Macromolecules and investigated a mystery in a lab. The mystery was who took Jeryll's ipod. We could discover who took his ipod by the evidence that was left behind which referred to what they ate for lunch. We had evidence B the dry and liquid form.

First we did a bunch of tests to see if the substances like vegetable oil, glucose, starch from corn or potatoes, powdered egg whites, and water have the presence of carbohydrates, lipids, nucleic acids and proteins.

This is what some of our tests looked like:

Then we did tests on the foods that the people ate like beans, pretzel, butter, jelly, fat free yogurt. We did the same tests on our evidence B.

This is what some of our tests also looked like:

Then based on all our results The evidence B best matched up with the fat free yogurt. The fat free yogurt was eaten by Ashley in the lunch break and therefore Ashley took Jeryll's ipod.

Day 6: House Case Analysis

Today in class we did our first house case, we were supposed to analyze the symptoms of an 18 year old boy and come up with the diagnosis.

His symptoms were:
Vomit
Severe Headache
Extremely tired
Confusion

And we had to come to class with the three ideas of what his problem could be. I thought he had dehydration primarily and then a concussion and then a migraine.

We got to ask questions about his details about his condition. Concussion could be ruled out because he suffered from no head injuries and migraine could be ruled out because he had no history of migraines in his family and there was no real loss of vision or sensitivity to light.

Then dehydration was ruled out by his actions. Because he drank 3 gallons of water before he ran. # gallons is too much and therefore he could be suffering from Hyponatremia. Also His serum osmolality test was a decreased number. Usually there is a osmolal gap when compounds are in high concentration. This evidence that he in took too much H₂O. 

Day 5: Graphing and Part 1/5 of the lab

Today we started of by constructing graphs out of class data and seeing how the best fit line works for all the data. The best fit line is pretty much the same for each graph. It intersects the x axis at the point of equilibrium when the solution in the dialysis tubing for example is the same molarity as the liquid outside.

Then we proceeded to do the rest of the Diffusion and Osmosis Lab.....

We did Part One with the starch and level of glucose. We put the dialysis tube which was originally clear and full of starch and glucose in the glass full of iodine and water. We saw a color change in the starch tube. Bits of the starch turned a dark blue color and looked like precipitate.

This lab part was a good example of Diffusion and Size. The starch molecules were too big so there was no real diffusion into the solution. But the glucose in the dialysis tube could go thru diffusion because it is small enough molecules to move.

We know the glucose got into the the water in the cup because we tested it with Benedict and saw a color change into orange.

The second part of the lab we took cubes of NaOH and added the element and the solution changed pink and then we let it sit. We took the cubes out later and spilt it in half. This is what it looked like:

Then we knew that some of the solution had gone into the cube of NaOH. If the white bit at the center is too big then it meant none of the nutrients of the solution didn't reach the nucleus. So therefore if the surface area was too big that is a indicator that the substance didn't soak up a lot.

Day 4: Diffusion and Osmosis Lab

Diffusion: All molecules are in motion and diffusion is the movement of molecules from an area of high concentration to an area of low concentration.

Osmosis: is a specialized type of diffusion which involves the transport if water thru a permeate membrane from a region of high concentration to a region of low concentration. Only some molecules are allowed to move thru the membrane.

Hypotonic: is a lower solute concentration(more water)
Hypertonic- is a higher solute concentration (less water)

Water moves from Hypotonic to Hypertonic

We began our lab in class

 Part 2: We were to determine the molarity of different color solutions ( red, blue, green, yellow, clear, purple) using dialysis tubes and water.

We placed one tube of each in water for 30 minutes and recorded the mass change. And then got the molarities for each:

Color	Mass Before	Mass After	Percent Change	Molarity
Clear	7.3g	7.9g	8.21%	.2M
Purple	8.1g	9.8g	20.988%	.8M
Yellow	7.6g	9.2g	21.053%	.6M
Red	8.1g	10.3g	27.162%	1M
Blue	7.3g	7.3g	0%	0M
Green	7.4g	8.4g	13.514%	.4M

This is what the tubes looked like afterward they were all more full after other than blue which didn't fill:

We also set up our energy drink (powerade experiment) and we saw what happened to them later that night.

This is what the powerade dialysis tubes looked like when we placed them in the cups of the different color solutions:

This is what the powerade tubes looked like after several hours and there was a color change and a decrease in mass:

 This was the percent mass change for the powerade:

Blue: 9.83%

Clear: -4.91%

Green:-22.95%

Yellow:-32.72%

Purple:-32.75%

Red:-54.09%

The other pair in our group Chris and Daniel peeled potatoes and dropped it in the solutions and waited several hours as well. This is their results:

Blue:21.95%

Clear:5.88%

Green:-36.67%

Yellow:-36%

Purple:-39.13%

Red:-66.67%

Day 3: Water

Today we learnt all about water.

We each got to choose a number to explain one of the aspects of Question 10 in the Unit 1 objectives.

Tanya and I answered: Why is a water strider able to walk on the surface of a pond without breaking the surface?

The answer to this question was a water strider is able to walk on the surface of the pond because water has a high surface tension because the molecules have a lot of cohesion. The cohesion is in the attachment of the hydrogen bonds, and the water strider can stand on the strong bond attractions, without breaking it. We learnt additionally to this answer we proposed, that the water strider's legs have a large surface area. The larger the surface area the more spread out the weight is.

The previous first questions were on: Why Coastal areas have milder climates than adjacent inland areas? or Why Ocean temperatures fluctuate much less than air temperatures on land? are very similar. Both of them are to do with molecular motion. Hydrogen bonds have the ability to move and break and reform. This ability causes the temperatures to go up on land when they break. Then down when the bonds reform. Soil also doesn't have any hydrogen bonds so can't regulate temperatures as well as oceans.

The fourth question explained was:   If you slightly overfill a water glass, the water will form a convex surface above the top of the glass. This is because the cohesion between the water molecules pulls them together above the glass because there is no longer any adhesion. It is convex because the angle of bent H2O molecules are 109.5 a large angle. 

The fifth statement to explain was:   If you place a paper towel so that it touches spilled water, the towel will draw in the water. This is because water molecules have a weak inter attraction (cohesion) compared to it’s attraction to another substance (adhesion), this is because of the hydrogen bonds. So the molecules of water adhere to the air pockets in the towel. 

The last statement that was explained to us is: Ice floating on Water. Ice floats on water because when water is liquid there is lots of motion and molecules can keep moving. When it is ice however, there is little motion in a solid and then there are pockets of air. The ice is then less dense and can float on the water. 

After listening to everyone explain their questions, larger groups were formed to answer questions about sweat. We sweat and dogs pant to shed excess heat. We can do this because water has a high heat of vaporization, so we use a lot of energy to vaporize the water molecules into the air. If it is humid however there are already water molecules in the air so it is harder to add ours and get rid of our sweat (in the form of vapor molecules).


We also did an experiment with a penny that should surface tension in water. We then learnt that surfectants (like soap) are substances that can break hydrogen bonds and the surface tension.

Red Cabbage has a pigment molecule called flavin which is an anthocyanin. Very acidic solutions will turn these pigment molecules into a red color. Neutral solutions will turn the pigment a purplish blue. Very basic solutions will turn the pigment a greenish yellow. The color of the juice reacts to the hydrogen and whether or not it donates or accepts a hydrogen ion. Acid rain would affect the growth of cabbage and increase it because more cabbages would become red. But eventually it would affect the development long term because increased exposure to acid rain is harmful to any living thing.