Honors Biology

1. Honors Biology Module 7 Cellular Reproduction and DNA November 14, 2013

2. Class Challenge Draw a picture of an animal or person By Bev Doolittle

3. Quiz Parts of a cell

4. Cellular Reproduction and DNA All living organisms reproduce. It is one of the four criteria for life. Scientists have tried to understand how an organism’s offspring receive the traits and characteristics that make then what they are. Sometimes the offspring and the parents look identical and other times you can hardly believe the offspring came from those parents.

5. The beginning of a real explanation for how traits are passed on from generation to generation was developed by a monk named Gregor Mendel in the mid 1800’s. He did careful experiments with peas, determining how pea plants reproduce and passed on characteristics to their offspring.

6. Hidden Away Unfortunately, this magnificent work was tucked away in a monastery for more than 50 years! When it was finally discovered, it laid the groundwork for all of our modern studies of genetics. Genetics: The science that studies how characteristics get passed from parent to offspring.

7. Building on the work of Gregor Mendel, Scientists today have determined that each organism contains a storehouse of information that governs its traits and characteristics. This storehouse is DNA and its main function is to tell the cell what proteins to make.

8. It may be hard to believe, but most of your traits and characteristics are governed by what kinds of proteins your cells make. Eye color is completely dependent upon what proteins are produces in some of the cells in your eyes. The coding for the production of certain proteins in your eyes, your DNA determines your eye color.

9. Inherent Limit set up by your DNA Not all of your traits are characteristics are completely determined by your genetic makeup. If you lift weights and workout, you will develop strong muscles. Even though you increase your strength, there is a fundamental limit to how strong you can become. Your DNA determines the general range of how strong your muscle can become.

10. Genetic Tendency It turns out that the majority of characteristics in your body are determined in this way. The DNA sets a range of possibilities.

11. You might have heard that Alcoholism is genetic. This is partially true. A Swedish study looked at alcohol use in 3000 children who were adopted and raised by nonrelatives. The incident of alcoholism was 2 1/2 times higher among those children who had at least one biological parent who was an alcoholic. What the data indicates is that DNA might set up an tendency towards or away from alcoholism, but that people can break that tendency.

12. DNA Your DNA alone does not determine who you are or what you will become. There are some traits (blood type, for example) that are completely determined by your DNA. However for many characteristics, your DNA just sets up a general framework. Within that general framework, what you do with yourself will ultimately decide what you become.

13. 3 Factors There are 3 factors that determine what kind of person you will be: • Genetic factors: The general guideline of traits determined by a person’s DNA.

14. 2. Environmental factors: Those “nonbiological” factors that are involved in a persons surroundings such as the nature of the person’s parents, friends and your individual behavior choices. “Free Will” Proverbs 23:7 “For as he thinks in his heart, so is he.”

15. Spiritual Factors: The factors in a person’s life that are determined by the quality of his or her relationship with God.

16. 2 Corinthians 5:17 (NKJV)  “Therefore, if anyone is in Christ, he is a new creation; old things have passed away; behold, all things have become new.” This means that anyone who belongs to Christ has become a new person. The old life is gone; a new life has begun!

17. These three factors work together to determine what kind of person you are. From a Christian point of view, spiritual factors are of the utmost importance for life, health and peace.

18. DNA is split up into little groups known as Genes. Gene: A section of DNA that codes for the production of a protein or a portion of protein, thereby causing a trait.

19. Your Genetic traits or tendencies are determined by what proteins are produced in your cells. A gene is actually coding for a particular genetic trait or tendency. In our second hour we will perform Experiment 7.1 DNA Extraction and hopefully actually see DNA strands.

20. OYO Question 7.1 Page 198

21. Transcription In multicellular organisms, specific cells have specific tasks which they must accomplish so that the organism will survive. In your body, you have skin cells that shield the inside of your body from contaminants. You have cells in your retina of your eye that detect light and sent electronic messages to your brain based on the light that they detect. How do these cells perform such radically different tasks?

22. Simply, they produce different types of proteins. The tasks that a cell can complete are dependent on the proteins that it produces. Before you see how a cell uses DNA to produce protein, you need to understand an important chemical of life, Ribonucleic Acid (RNA) .

23. RNA Is made up of nucleotides, but the individual structure of the nucleotides is a bit different. The sugar that makes up the foundation of nucleotides is ribose, not deoxyribose (as in the case of DNA).

24. RNA Unlike DNA, they do not form a double helix. 1. RNA forms a single strand of joined nucleotides. 2. RNA has four nucleotides bases. 3. 3 of the RNA strands are like DNA’s (adenine, cytosine, and guanine), one of them is different (uracil).

25. Uracil performs the same tasks in RNA that thymine does in DNA. RNA has uracil in place of thymine. Don’t be confused… When you are thinking about RNA, just remember that uracil takes the place of thymine. DNA is much more stable than RNA because DNA uses thymine and deoxyrobose instead of uracil and ribose.

26. This means it is unlikely to undergo major changes with time, making it the ideal molecule for storing information from generation to generation, so that each organism reproduces after its own kind. (Genesis 1:11)

27. RNA has a lot of similarities to DNA, but also some differences. Why is it important in the process of how the cell makes proteins? RNA acts like a camera.

28. The main portion of a cell’s DNA is in its nucleus, but proteins are made in the ribosomes which are outside of the nucleus. To get information from the nuclear DNA to the ribosomes, one type of RNA makes a “snapshot” of the DNA and takes that information out of the nucleus to the ribosome.

29. How is that Done? Certain nucleotide bases can only link to other nucleotide bases. RNA has nucleotide bases. It has cytosine, guanine, and adenine, just like DNA. But RNA also has Uracil. The RNA can link its nucleotide bases to the bases on the DNA. • The uracil in RNA links up to the adenine in DNA. • So the then the Adenine in the RNA can link to the thymine in DNA, • the cytosine in RNA can link to the Guanine in DNA, and • the guanine in RNA can link to the cytosine in DNA.

30. What does all this accomplish? When RNA does its job, it produces a “negative” of the DNA section that it is copying. Everywhere the DNA has a cytosine, the RNA will have a guanine. Everywhere DNA has a guanine, the RNA has a cytosine. Everywhere the DNA has a thymine, the RNA will have an adenine Everywhere DNA has adenine, the RNA will have a uracil.

31. This is much like what happens when film is being developed. During the developing process, the first thing to appear is a negative. The negative is dark everywhere that the picture is supposed to be light, and it is light everywhere that the picture is supposed to be dark. Based on this negative, then a picture can be made.

32. Dr. Wile’s animation CD

33. Transcription: Figure 7.1 Based on the “negative” produced by RNA, a protein can be made. When the RNA strand is built, it is a negative image of the DNA strand to which it linked. This process is called transcription, and the negative image produced by transcription can be used by the ribosome to make a protein.

34. Translation After transcription, the RNA leaves the nucleus and moves to the ribosome. This carries the negative image of the gene that was transcribed to the organelle that produces the protein. Because the RNA that performs transcription is essentially a messenger (sending instructions from the nuclear DNA to the ribosome), we call this a Messenger RNA (mRNA).

35. In order to get the DNA’s instructions from the nucleus to the ribosome, the RNA produces a negative image of the DNA;s nucleotide sequence and takes it to the ribosome. The ribosome is surrounded by amino acids, enzymes, and a different kind of RNA called transfer RNA (tRNA). Transfer RNA is a big molecule that contains a special sequence of three necleotides called Anticodon (a three-nucleotide base sequence on tRNA)

36. Translation: Figure 7.2 A strand of mRNA can be thought of as a bunch of three-nucleotide sequence. Each three-nucleotide base sequence is called a codon. A strand of tRNA contains a three-nucleotide base seque4nce called an anticodon. A certain anticodon on tRNA results in an certan amino acid boded to the tRNA. Since the tRNA anticodons are attracted by the mRNA codons, the net result is that a codon on mRNA attracts a specific amino acid.

37. Translation Explained When the tRNA strands have linked up to the mRNA, there are amino acids lined right up next to each other. So what is a protein? It is a bunch of amino acids linked together in a particular sequence. This happens again and again, so that many, many amino acids link up together. When all the amino acids called for by the codons on mRNA are linked together, the result is a protein.

38. When a cell needs to make a protein, its DNA has the plan for making that protein in a long series of three-nucleotide base sequences. Messenger RNA reads this sequence and makes a “negative image” of the relevant portion of DNA. It then takes this series of nucleotide base sequences out to the ribosome. Once at the ribosome, each codon (set of three nucleotide bases) on the mRNA will attract a particular anticodon (set to three nucleotide bases) on tRNA. The tRNA that is attracted to the codon has a particular amino acid riding on it. This amino acid is determined by the anticodon on the tRNA. Since each codon on mRNA attracts a particular anticodon, the condons attract a particular amino acid. As the amino acids line up, they link together, forming a protein.

39. Transcription and Translation This process we just went over is split into two phases: • Transcription • Translation

40. Transcription mRNA makes its negative image in order to copy the nucleotide sequence in DNA. This is like a transcriptionist “copying” a conversation by writing everything down.

41. Translation The mRNA leaves the nucleus and goes to the ribosome, where the tRNA strands carry amino acids to the mRNA and line them up in the order determined by the sequence of nucleotides. The amino acids then bond together, making a protein. The “language” of the nucleotide base sequences in RNA is translated into the “language” of amino acid sequences in a protein.

42. transcription translation DNA ----- RNA ----- Protein See figure 7.3

43. For Further Explanation Mr. Anderson’s Youtube

44. Mendelian Genetics http://youtu.be/NWqgZUnJdAY

45. What is DNA? http://youtu.be/q6PP-C4udkA Transcription and Translation http://youtu.be/h3b9ArupXZg DNA Replication http://youtu.be/FBmO_rmXxIw

46. Mitosis and Meiosis Simulation http://youtu.be/zGVBAHAsjJM Mitosis http://youtu.be/1cVZBV9tD-A

47. Experiment 7.1 DNA Extraction OBJECT: To extract DNA from peas so that you can see what DNA looks like on a macroscopic scale.

48. Onion root tip http://youtu.be/mUBlZ1VNReQ