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Number...Assignment.................................Date Due.

Extra Credit...........................................
You can write paragraphs on any life science topic for extra credit.

For me to accept written work as extra credit, I will need the following:
1. A list of facts on a topic. (Better yet the facts would be in an outline.)
2. Your own topic sentences that link together your list of facts in a logical way.
3. Written paragraphs composed by you that contain these topic sentences and facts.

One way to write paragraphs on a topic is to:
1. Create a list of question about the topic.
2. Collect facts that answer these questions.
3. Create topic sentences that group and link the facts you collected in a way that makes sense.
4. Write a paragraph that includes the topic sentences and their related facts.

1. For example, a list of questions might look like this:
What is the organ's importance?
Where is the organ located in the body?
What is the organ's structure or parts?
What organ system is it part of?
What is the organ's function in its organ system?
What is the organ's relationship or connections to other organs?
What are some diseases related to the organ?
What are some health practices can keep the organ healthy?

2. Make a list of facts that answers each of the above questions?

3. Compose topic sentences that group and relate facts that go together.

4. Compose paragraphs using your topic sentences and their related facts.

You could use the above as a guide to write about any body part.
I would give you some points for the list of questions.
I would give you more points for facts that answer answer your questions.
Composing topic sentences involves more thinking, so they would earn a greater number of points.
Composing paragraphs also involves more thinking, so they would earn a greater number of points.

#37......Two Column Genetics Notes............Due 3/24
(Late papers will not be accepted just as the Substitute Teacher told you.)
Copy each note and then rewrite the note using other words.
Copying is 40% and rewriting is 60% of the grade.
1. Genes are the many separate instructions for the many different proteins and traits of an organism.
2. There are two copies of each gene, one from the mother and one from the father.
3. These genes can take different forms called alleles.
4. Genes are located on specific sections of the chromosomes in the nucleus of a cell.
5. Genes come in pairs and offspring inherit one copy of each gene from each parent by random chance.
6. A dominant allele is one whose trait always shows up, when the organism has two different alleles.
7. A dominant allele is shown by a capital letter and recessive alleles are shown by lower case letters.
8. A recessive allele is one that is hidden when the other copy of the gene contains the dominant allele.
9. A recessive allele shows up only when an organism has two recessive alleles.
10. Offspring with two dominant alleles, (one dominant gene from each parent) are said to be homozygous dominant.
11. Offspring with two recessive alleles, (one recessive gene from each parent) are said to be homozygous recessive.
12. Offspring that inherit one dominant gene and one recessive gene are said to be heterozygous dominant.
13. Traits are called co-dominant when they do not follow the dominant-recessive pattern, but show a blending of alleles.
14. An example of co-dominance would be getting a pink flowered offspring when crossing red and white flowered parents.
15. An organism's genotype indicates the two alleles present for a particular trait.
16. An organism's phenotype is the observable trait that is expressed, in other words what it looks like.
17. The probability of certain traits being shown in offspring can be figured by using Punnett Squares.
18. A Punnett Square is a chart that shows all the possible combinations of alleles that can result from a cross of two genotypes..
19. The ratio of the number of ways an outcome may occur to the number of total possible outcomes for the event is its probability.

#36......Genetics Introduction.....................3/31/09
Copy as notes.
1. Genetics is the study of how traits are inherited through the interaction of alleles.
2. Heredity is the passing of traits from parent to offspring.
3. An organism has two genes for each trait.
4. Genes can have more than one expression and each different expression is called an allele.
5. During meiosis when sex cells are made, the two alleles separate into different sex cells.
6. Alleles or the two copies of a genes can be represented by two letters.
7. One expression of the gen or allele is represented by a capital letter and the other by a lower case letter.
8. A genotype is the genetic make up of an organism.
TT = homozygous = purebred
Tt = heterozygous = hybrid
tt = homozygous = purebred
10. Phenotype is the expression the alleles present or how the organism looks.

Restart numbering
1. Genetics: The study of how traits are inherited through the interaction of alleles.

2. Heredity is the passing of traits from parents to offspring.

3. A trait is a characteristic that can be passed from parent to offspring.

4. Traits are controlled by genes on the chromosomes.

5. Gregor Mendel :
Father of genetics
He recognized the importance of using math in research
His experiments were beautifully designed following the scientific method
Gathered statistics on over 20,000 pea plants

6. Using statistics math lead him to the ideas of:
Dominant and recessive
Law of segregation
Law of independent assortment

7. Mendel's work was discovered 50 years later separately by three scientist while doing research.
Mendel's Pea Plants:
He became the pollinator himself
He controlled which plants mixed.
He performed cross-pollination with a paintbrush
He cut of the flowers pollen producing structures to stop self pollination

8. Mendel studied seven traits of pea plants and these traits were expressed in similar patterns when plants with them were crossed.
Height, Pod appearance, Pod color, Seed texture, Seed color, flower color, and position of flower on the stem.

9. Mendel observed that, if pure bred purple flowered plants and pure bred white flowered plants were crossed, all the offspring would have purple flowers. He also observed that, if these offspring were crossed, three out of four of the resulting plants would have purple flowers, but one out of four plants would have white flowers.

10. Mendel wanted to explain how a trait could disappear for one generation and reappear the next.

11. Mendel was able to describe what happen when crossing plants, but others would discover chromosomes and genes with advances in microscopes.

12. Alleles are one form of a gene.

13. Sex cell have one form of a gene, because they only have one of each kind of chromosome.

14. Body cells have two genes for a trait because they have two chromosomes. This mean they can have two identical alleles or two different alleles.

15. One may be dominant over another. If this happens, the dominant gene is the one expressed. If not, the recessive trait is expressed.

16. A Dominant trait will always be expressed and will “mask” a recessive trait

17. A recessive trait can only be expressed if there are no dominant alleles present.

18. Steps for using a Punnett square:
Capital letters indicate dominant alleles
Lower case indicates recessive alleles
One parent's genotype (alleles) goes along the top.
The other parent's genotype goes down the side.
Fill in the boxes using what is above and beside it.

19. Punnet squares show probabilities and not actual results.

If B is brown eye color and b is blue, how many genotype are there? Phenotypes?

20. Punnett squares are used to predict the traits in offspring and in what ratio.

21. Monohybrid crosses are shown with a Punnett square of one trait.

22. Dihybrid crosses are shown with a Punnett square of two traits.

23. Law of Segregation – during gamete formation pairs of factors for one trait (Alleles) separate.

24. Law of Independent Assortment- alleles for different traits go into different gametes randomly.

Page 131. Draw the Punnett squares and answer the questions.

#35......Focus Items /Participation............3/31/09
You must be present and working to earn credit.
23 items total.

#34......DNA Extraction Activity............3/20/09

Some basic, but cool, chemistry…
DNA is the largest known molecule. A single unbroken strand can contain millions of atoms. When DNA is released from a cell it typically breaks up into short strand fragments. These smaller fragments have a slightly negative electric charge. Salt ions, common in many solutions, are attracted to the negative charges on the DNA fragments. By controlling the salt concentration of the solution, DNA can remain fragmented or become very “sticky” and form large globs of molecular material.

Releasing the DNA…
The first step in obtaining DNA is to release the DNA from the cells of raw wheat germ. Detergents and soaps break down cell and nuclear membranes, releasing the DNA, and they also break up proteins that may harm the DNA. The released DNA dissolves in the water and will float upwards. The colored layer of liquid above the wheat germ will contain DNA and proteins. The DNA will then move up to a layer of alcohol carefully placed above the water. DNA doesn't stay dissolved in alcohol, but precipitates out and will appear as a white stringy mass.

Spooling the DNA on a stick…
Alcohol allows DNA fragments to stick together, or precipitate, producing a blob of DNA that you can examine. The DNA precipitate can be captured, or spooled, onto a wooden stick by placing it in the DNA and turning it. If you want to save your DNA, you can transfer it to a small container filled with alcohol.

Items needed
Tall narrow container/flower vase
Liquid dish soap or Woolite
90% Alcohol or higher
Wheat Germ uncooked/not toasted
Salt (if desired)

Step 1: Fill your container 10 percent full of wheat germ. Also add 10 to 40 grains of table salt.

Step 2:, Add water to the wheat, germ filling until the container is 40 percent full.

Step 3 : Add about ½ percent of the container's volume of dish detergent the water. (small squirt)

Step 4: Gently, gently, and even more gently stir the soap, water and wheat germ slowly. Let it set set 3 minutes, allowing the soap to work. (The soap will help break down the cellular walls and nuclear membranes of the wheat germ cells. This will free the DNA that is inside.)

Step 5: Fill your container up with Alcohol. Put the alcohol in slowly by tipping your container slightly by running the alcohol down the side of the container.

Step 6: Watch the DNA begin to float up into the alcohol. Give it at least 10 minutes or more.

Step 7: Do the extraction more than once with different amounts of stirring to see its effect on the amount and form of DNA extracted.

(To improve the result you could try mixing the water and salt ahead of time. 2 grams salt to 90mL water. The alcohol could be chilled by placing the container holding it in an ice water bath.)

Lab Questions:
1. After step 6, what did you see in the alcohol and describe what it looked like?
2. What is another word or phrase for DNA?
3. What 4 nitrogenous bases are found in DNA?
4. What part of the cell did the DNA come from?
5. What usually keeps the DNA in its usual place in the cell?
6. What are cell membranes and nuclear membranes made of?
7. What does soap do to the stuff that membranes are made of?
8. Why do you think the soap helped to free the DNA?
9. DNA is less dense than water & alcohol. Why does the DNA move up into the alcohol?
10. We want the DNA to clump together, but like charges repel and DNA has a negative charge. Salt can provide a positive charge, so what is its purpose?

DNA and Membrane Facts:
Copy as notes.
1. Living things are made of Nucleotides, Lipids, Proteins, and Carbohydrates.
2. DNA is a long, twisted, double chain of nucleotides that contains the genetic code.
3. Nucleotides are made a sugar, a phosphate and a base. (Complementary: A pairs with T and C pairs with G)
4. Membranes are made of lipids, such as the nuclear membrane. (Fats and oils are lipids)
5. Soaps cause lipids to break up in water, so soaps can be used to break up membranes.
6. Water attracts DNA, so it dissolves it, but alcohol repels DNA, so DNA forms a precipitate.
7. Opposite charges attract each other. In other words oppositely charges items neutralize each other when they come together.

Just read
After the Exploration
Expected Results
...A slimy white material will precipitate at the interface of the ethanol and filtrate layers. This material consists of clumped-together DNA strands and some protein.
What's Going On?
...The procedure used in this activity has the same essential elements as more advanced laboratory DNA extraction procedures: mechanical and thermal disruption of cells, liberation of the DNA, and precipitation of the DNA.
...In this procedure, the wheat germ cell walls are broken down by the mechanical mashing and then the heating, and the detergent dissolves the lipids in the cell membranes and nuclear envelope (just like the detergent dissolves grease on your dishes). No longer confined inside nuclear membranes, the DNA--highly soluble in water because the phosphate group of each nucleotide carries a negative charge&emdash;goes into solution. However, the positively charged sodium ions from the salt in the extraction solution are attracted to the negatively charged phosphate groups on the DNA backbone, effectively neutralizing the DNA's electric charge. This neutralization allows the DNA molecules to aggregate with one another. When the ethanol is added, the DNA clumps together and precipitates at the water/ethanol interface because the DNA is not soluble in ethanol.
...Each glob of material in the precipitate will contain millions of DNA strands clumped together, along with some of the protein that is normally associated with DNA. (Since the DNA was not highly purified, some protein precipitates out with the DNA.) The yellowish water below the alcohol will contain dissolved proteins and some DNA that hasn't risen into the alcohol.

#33......4th Chapter Review A.....................3/12
1. Cell division produces more cells and is how organisms grow and get bigger.
2. Cell division is how organisms repair damaged or worn out cells.
3. Cell division occurs often for cells that wear out or are replaced often, such as blood and skin cells.
4. Cell division is use by organisms for reproduction, such as making sex cells.
5. The cell cycle has two parts: a period of growth and development and the process of cell division.
6. Interphase is the period of growth and development part of the cell cycle.
7. Mitosis is the cell division part of the cell cycle.
8. Cell spend most of their life the growth and development phase called interphase.
9. Cells that no longer divide like nerve and muscle cells stay in interphase.
10. For cells that continue to divide, two copies of a cells genetic material are produced during interphase through the process of replication.
11. During cell division, first the nucleus and then the cytoplasm divides.
12. Mitosis is the process through which the nucleus divides.
13. Cytokinesis is the process through which the cytoplasm divides.
14. The process of mitosis produces two identical nuclei.
15. As the nucleus starts to divide, the DNA forms structures called chromosomes.
16. Chromatids are the duplicated copies of a chromosome that are connected at a centromere.
17. In sister chromatids, the DNA is coiled tightly into identical, thickened strands that form an X shaped structure.
18. Mitosis can be divided into prophase, metaphase, anaphase, and telophase.
19. During prophase the chromatid pairs become visible and the nuclear membrane breaks down.
20. In animal cells, structures called centrioles, where the spindles fibers attach, move to opposite ends of the cell.
21. During metaphase the chromatid pairs line up across the cell.
22. During anaphase, the chromatid pairs separate.
23. During telophase, the cytoplasm begins to separate and nuclear membranes start to form.
24. In plant cells, a cell plate forms between the two new daughter cells during telophase.
25. In animal cells, the cell membrane pinches in the middle like a string tightening around a balloon during telophase.
26. After cytokinesis the cell returns to the growth and development phase called interphase.
27. Pairs of chromosome are found in most cells. Sex cells don't have pairs of chromosomes.
28. Humans have 46 chromosomes or 23 pairs.
29. One of each chromosome in a pair comes form a different parent. 23 Chromosomes come from the father and 23 come from the mother.
30. Chromosomes are studied by taking a picture of them and placing them from longest to shortest in pairs. Dark and light patterns are used to match pairs up.
31. Pairs of chromosome have the same genes, but have slight differences that produce different traits.
32. Offspring are produced by one parent in asexual reproduction
33. Some plants reproduce asexually with runners.
34. Bacteria divide to asexually reproduce identical copies in a process called fission.
35. Some organism like the hydra reproduce by budding, which is when a new organism grows from the body of the parent.
36. Regeneration is when an organism can regrow a lost or damaged body part with mitosis.
37. Sexual reproduction is why everyone is different.
38. Fertilization is the join of two sex cells, such as an egg and sperm, and produces a zygote.
39. Sex cells are haploid meaning they only have one set of chromosomes or 23 for people.
40. Body cells are diploid and have 23 pairs of chromosomes where half of each pair comes from the father and the other half from the mother.
41. Sex cell don't get all their chromosomes from one parent or the other, but get a random mixture from from both parents.
42. Sex cells have half the chromosomes of body cells, consisting of one of each kind of chromosome.
43. Meiosis produces haploid sex cells, so it use cells with pairs of each chromosome and makes cells with only one of each kind.
44. During meiosis the nucleus is divided twice.
45. The two divisions of meiosis have the same steps as mitosis and are called meiosis I and meiosis II.
47. During Meiosis I chromosome pairs come together and trade parts through a process called crossing over.
48. In meiosis I, chromosomes pairs are separated into two cells.
49. The two cell from meiosis I divide, so four cells are produced in tolal.
50. When the chromatid divide in meiosis II, the sex cells produce have half the number of chromosomes as the original cell.

#32......Demostrate Translation using the model
Protein Synthesis Model Print the pages at this link.

#31......Demostrate Transcription using the model
Protein Synthesis Model Print the pages at this link.

#30......Protein Synthesis review...........3/12
Answer the Questions.
1. What is protein synthesis?
2. What is a gene?
3. Where does transcription occur?
4. Where does translation occur?
5. What is used as (a template) instructions in transcription?
6. What is produced by transcription?
7. What does messenger RNA do?
8. What does a ribosome do?
9. How is mRNA used at the ribosome?
10. What does transfer RNA do?
11. How is tRNA used at the ribosome?
12. What does complementary bases mean?
13. What is produced by translation?
14. What are three bases on mRNA called?
15. What are the three bases on tRNA called?
16. What is a protein made of?

#29......Protein Synthesis Facts...................3/11/09
Write the notes.
1. Proteins are the building blocks and the controlling molecules of living things.
2. Proteins are made of chains of 10 to 30,000 units called amino acids.
3. Each kind of protein has a different sequence(order) of amino acids.
4. There are around 20,000 different protein in humans, making everything from antibodies to muscle fibers.
5. DNA contains the code or instructions for making proteins.
6. A gene is the code for a protein on the DNA.
7. The instructions for making proteins are transcribed from the DNA into mRNA in the nucleus.
8. Transcription makes an RNA copy of the code in the DNA and both these codes are a sequence of bases.
9. After being made in the nucleus, messenger RNA travels from the DNA to the ribosomes in the cytoplasm.
10. Ribosomes are the small cell structures where proteins are made.
11. Ribosomes are made of ribosomal RNA and proteins upon which proteins are synthesized(made).
12. Transfer RNA brings amino acids to the ribosomes where they are connected like adding links to a chain.
13. Ribosomes move down the mRNA three bases at a time when making a protein.
14. Amino acids are connected in the correct order because the bases on the tRNA must match up with based on the mRNA, before the amino acid it carries is connected by the ribosome.
15. The matching up of tRNA bases with mRNA bases is called translation.
16. Translation occurs three base pairs at a time and once all the base on the mRNA have been translated, the amino acid chain is complete.
17. These chains of amino acids then are folded into specific shapes to complete the protein.
18. The instructions for making a protein are on the DNA in the nucleus.
19. A gene is the genetic code for how a protein is made.
20. Protein Synthesis is the two step process of making a protein.
21. Transcription is the making of messenger RNA.
22. Transcription used a gene as a template to make a piece of messenger RNA.
23. Messenger RNA are the instructions that ribosomes use to make a protein.
24. Translation is the second step of protein synthesis and occurs at the ribosome.
25. At the Ribosome, the base on the messenger RNA are matched by bases on transfer RNA.
26. Transfer RNA brings amino acids to the ribosome to be connected in the correct order.
27. Once the bases on the mRNA and tRNA are matched the ribosome connects the amino acid.
28. When the ribosome reaches the last three bases on the mRNA, it releases the mRNA and chain of amino acids.
29. This chain of amino acids then is folded into a protein.

#28......Transcription and Translation figures.
Sketch the diagrams and write the text show below.


#27......Protein Synthesis Questions....................3/3
1. Define protein.
2. Define amino acid.
3. Define gene.
4. Define enzyme.
5. What is protein synthesis?
6. What do genes code for?
7. What are genes made of?
8. What in a gene determines a proteins compostion?
9. When is a gene expressed?
10. How many strands make up DNA?
11. How many strands make up RNA?
12. Which base is found in DNA but not RNA?
13. Which base is found in RNA but not DNA?
14. What are the three types of RNA?
15. What is the first stage of protein synthesis called?
16. What happens in the first stage of protein synthesis?
17. What is the second stage of protein synthesis called?
18. What happens in the process of translation?
19. What does RNA polymerase do?
20. What base matches adenine in RNA?
21. What must happen before mRNA can leave the nucleus?
22. Where does transcription occur?
23. Where does translation occur?
24. What are proteins made of?
25. What does translation involve?
26. What makes a ribosome ready to translate a protein?
27. What does tRNA do?
28. What happens to produce elongation?
29. What is a codon?
30. What is an anticodon?
31. On what are codons found?
32. On what are anticodons found?
33. What do codons and anticodons ensure?
34. What are the two codons called that don't code for amino acids?
Protein Rules (Protein Synthesis)
Protein has a role in virtually every activity of every organism, from the respiration of a bacterium to the blink of an elephant's eye. Organisms make the proteins they need through a process called protein synthesis. Protein synthesis is the process by which an organism's genotype (the genetic makeup) is translated into its phenotype (the traits). An organism's phenotype depends on the formation of specific structural proteins based on its genotype.

Genes code for the sequence of amino acids that make up proteins. A gene is made of DNA. The sequence of DNA bases in a gene determines the composition of one or more proteins. You can think of DNA as a template, or pattern, for making proteins.
Some genes code for proteins that regulate the expression of other genes; that is, they determine which genes are expressed at a given moment and which are not expressed. A gene is "expressed" when the protein that it codes for is synthesized.

DNA works with another nucleic acid-ribonucleic acid, or RNA. The structural differences between DNA and RNA are shown in Figure 8.1. RNA is a single-stranded nucleic acid that is involved in protein synthesis. There are three types of RNA, messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). Each type has a specific function.

Protein synthesis occurs in two stages. During the first stage-called transcription-the genetic information from a strand of DNA is copied into a strand of mRNA, The word "transcribe" means "to copy" You can see the steps of transcription in Figure 8.2.

The second stage of protein synthesis is called translation. You may be familiar with this word. Translation in cells is similar to translation in speech or writing. In cells, translation is a process by which the "language" of nucleic acids (bases) is changed into the "language" of proteins (amino acids).

In order for genes to be expressed, the DNA in chromosomes has to be made accessible. Recall from Figure 7.7 that DNA is coiled and wound in chromosomes. Inactive DNA is tightly coiled, whereas active DNA is loosely coiled. The coiling and uncoiling of DNA is one way of controlling gene expression. Scientists hypothesize that chemicals such as growth factors and hormones cause chromosomes to tighten or loosen their coils.

BUILDING RNA: (Making the messenger)
Transcription is the process of transferring genetic information from a strand of DNA to a strand of mRNA. Once the chromosome coils loosen, transcription can begin with RNA polymerase (POL-ih-meh-rayz). This enzyme separates the two strands of a DNA double helix, exposing the base pairs of a gene. Unattached RNA bases are present in the nucleus. RNA polymerase matches RNA bases with the complementary bases on one strand of the DNA template. As you see in Figure 8.2, RNA bases (U, A, G, and C) bind with complementary DNA bases (A, T, C, and G). Note that in RNA it is uracil, not thymine, that binds with adenine. Because of these specific binding patterns, the precise code is copied, or transcribed, from DNA to mRNA.

In prokaryotic cells, which have no nuclei, mRNA travels directly to a ribosome. In fact, both transcription and translation can proceed simultaneously in prokaryotes. Because proteins are made quickly, prokaryotes can multiply rapidly. This rapid reproduction is one reason you get sick so quickly when infected by some disease-causing prokaryotes, such as the bacterium that causes strep throat.

In eukaryotic cells, or cells with nuclei, mRNA must go through an additional step before it reaches a ribosome. This additional step, shown in Figure 8.3, is called RNA splicing. DNA in eukaryotic cells contains regions that do not code for proteins. These noncoding regions of DNA or RNA are called introns. The sections of DNA or RNA that do contain codes for proteins are called exons.

DNA introns and exons are both transcribed into mRNA. Before the mRNA leaves the nucleus, enzymes remove the introns and join the exons to one another. In this way, mRNA is spliced, or cut and rejoined, and the mRNA that leaves the nucleus includes only exons.

RNA splicing is an important step in protein synthesis in eukaryotes. It controls the genetic information that leaves the nucleus. Once the introns are removed, mRNA leaves the nucleus and moves to a ribosome in the cytoplasm, where translation occurs.

During translation, genetic information carried by mRNA is translated to form proteins. As you learned in Chapter 2, proteins are made of specific sequences of amino acids. Translation involves linking amino acids together into these sequences.

In the cytoplasm, mRNA attaches to a ribosome, a tiny organelle that can be found either floating freely in the cytoplasm or attached to endoplasmic reticulum. The ribosome, with its attached mRNA, is now ready to synthesize a protein. Figure 8.4 shows the interactions of mRNA and ribosomes during the second stage of protein synthesis, translation.

During translation, a tRNA molecule transfers an amino acid to the ribosome. The tRNA's main function is to transport amino acids. As shown in Figure 8.4 each new amino acid links with the previous amino acid, forming an amino acid chain. As more and more tRNAs arrive, each with an amino acid, the chain grows longer. The lengthening of the amino acid chain is called elongation.

You might wonder how tRNA delivers the amino acids in the correct order. This sequencing is done through a system of complementary codons and anticodons. A codon is a three-base section of mRNA. Most codons carry a code for a specific amino acid. For example, the codon GCU (guanine, cytosine, uracil) codes for the amino acid known as alanine AL-uh-neen).

An anticodon is a sequence of three bases found on tRNA. Each tRNA carries only one anticodon, in contrast to the many codons in an mRNA molecule. Each tRNA anticodon complements a specific mRNA codon. For example, the mRNA codon AGU is complemented by the tRNA anticodon UCA. Based on what you know about complementary base pairs, what is the tRNA anticodon for the mRNA codon GCU? For the mRNA codon GCA?

Anticodons and codons fit together in much the same way as plugs fit into sockets. The codons and anticodons ensure that the amino acids are linked in the proper order. Because a specific amino acid attaches only to a tRNA with a specific anticodon, the tRNA carries the appropriate amino acid when it plugs into its complementary mRNA codon.

Several codons on mRNA have a different purpose. These codons do not code for an amino acid; they are the "start" and "stop" codons. The start and stop codons do exactly what their names suggest. They signal a ribosome to either start or stop translation. As you would expect, these codons are located at the beginning and end of a mRNA code for a particular protein.

The codes for amino acids, as well as the start and stop codons, are universal. In humans, mice, bacteria, or viruses, GGG translates to the same amino acid: glycine (GLY-seen). The universal start codon is AUG, which codes for methionine. UAA, UAG, and UGA are the three universal stop codons. You can see all the codons and the amino acids they code for in the table on page 187. The fact that all viruses and organisms share the same codons demonstrates the basic unity of life on Earth.

#26......Coastal Creatures.............................2/27
20 questions on Patagonia, Sea Lions, Orca, and Elephant Seals.

#25......Phases of Meiosis............................2/26
Reproduce the Meiosis figure.
Pay attention to the different color chromosomes, because they come from different parents.
Note the crossing over of genes between chromosome pairs. (homologous chromosomes)
Meiosis Phases Summary

#24......Meiosis Questions B..................2/25
1. What happens in Prophase I?
2. How many similar sister chromatids get together in prophase I?
(Crossing over occurs in prophase I.)
3. What happens in Metaphase I?
4. How is this different than metaphase in mitosis?
5. What happens in Anaphase I?
6. What separates in anaphase of mitosis?
7. What happens in telophase I?
8. In prophase I, are there one or two of each kind of “X” structure?
9. In prophase II, are there one or two of each kind of “X” structure?
10. What do we call these “X” structures?
11. What happens in prophase II?
12. What happens in metaphase II?
13. What happens in anaphase II?
14. What separated in anaphase of mitosis?
15. How many cells are present with the completion of telophase II?
16. Describe the chromosome number in the cells after telophase II?

#23......Meiosis Questions A.................2/24
1. Define diploid.
2. Define haploid.
3. What kind of cells are diploid?
4. What kind of cells are haploid?
5. How many chromosomes are in a diploid, human cell?
6. How many chromosomes are in a haploid human cell?
7. How do the chromosomes of human body cells and sex cells compare?
8. What does the process of meiosis produce?
9. Why is it important that sex cells be haploid?
10. How many divisions occur in meiosis?
11. What is the first division of the process that produces haploid cells called?
12. What is the second division of the process that produces haploid cells called?
13. What chromosome process occurs before meiosis?
14. What is an homologous pair?

#22......Focus Items......................................2/27
#22 Focus Items
1. The Mitosis model pieces represented sister chromatids
2. Sister chromatids are the identical copies of a chromosome replicated during interphase.
3. The first phase of mitosis is prophase.
4. During prophase, sister chromatids become visible
5. The second phase of mitosis is metaphase.
6. During metaphase, sister chromatids line up across the middle of the cell.
7. The third phase of mitosis is anaphase.
8. During anaphase the sister chromatids separate and start moving to opposite sides of the cell.
9. The fourth phase of mitosis is telophase.
10. During telophase, the cytoplasm starts to separate and new nuclear membranes start to form.
11. The two new cells are called daughter cells and have identical nuclei.
12. Replication is the process which produces two identical copies from an original chromosome and occurs during interphase.
13. The model pieces represent nucleotides which are made of a phosphate, a sugar, and a nitrogenous base.
14. First step, an enzyme (a special protein) starts unzipping the DNA's base pairs.
15. Second step, free nucleotides are matched to the exposed bases of the original strands.
16. The sugars and phosphates of the free nucleotides are connected to complete each new half of the DNA's strands.
17. Tell what mitosis is.
18. Tell what happens to the chromosomes in interphase.
19. Tell what happens in prophase.
20. Tell what happens in metaphase.
21. Tell what happens in anaphase.
22. Tell what happens in telophase.
23. Tell what replication is.
24. Meiosis is the process that produces sex cells and is why everyone is different.
25. Meiosis divides a cell twice.
26. Meiosis I separates chromosome pairs and randomly puts a full set into two new cells.
27. Meiosis II separated sister chromatids and randomly puts a full set into two new cells
28. Meiosis starts with 46 sister chromatids or 92 total.
29. Meiosis I puts 23 sister chromatids into two cells each.
30. Meiosis II put half the the sister chromatids into two cells, so each one has 23 chromosomes.

#21.....Demonstrate Replication using your paper model
1. What do the model pieces represent?
2. What is replication and when does it occur?
3. First step of replication?
4. Second step of replication?
5. Third step of replication?

#20.....Demonstrate Mitosis using your paper model
1. What does the model piece represent?
What process occurs involving the chromosomes during interphase?
2. First phase of mitosis? (Name it and tell what happens.)
3. Second phase of mitosis?
4. Third phase of mitosis?
5. Fourth phase of mitosis?

#19......DNA Structure and Replication.............2/20
Draw and include text for figure 7.3 below. Learn the three parts of nucleotides and how they fit together.
Draw and include text for fugure 7.6 below. Learn the three steps to DNA replication.

#18......Focus Items ....................................2/20
2/17 (Concepts were also presented in picutres.)
1. Mitosis sorts replicated DNA sets to get two identical nuclei from the original.
2. Meiosis reduces the number of chromosomes by half, one of each pair of chromosomes.
3. Replication is the process that produces two identical copies of each chromosome.
4. Each chromosome is a piece of DNA.
5. The DNA molecule has the shape of a twisted ladder or double helix.
6. The two sides of the DNA molecule are made of alternating sugar and phosphate molecules.
7. Two, joined nitrogen bases connect the two sides of DNA like the rungs of a ladder.
8. A joins with T to connect the two sides of DNA.
9. C joins with G and also connects the two sides of DNA.
10. A is complementary with T and C is complementary with G.
11. In replication the DNA unzips, the bases pair up, and the side strands bond resulting in two identical strands.
2/18 (Concepts were also presented in pictures. Two different sets.)
12. DNA is made up of nucleotides.
13. Nucleotides have a sugar, a phosphate and a nitrogen base.
14. The sugars and phosphates of nucleotides make up the “sides” of DNA.
15. The nitrogen bases of nucleotides connect the two “sides” of DNA like rungs in a ladder.
16. There are four kinds of nucleotides because there are four kinds of bases.
17. Nucleotides can contain the bases: A, T, C, or G.
18. Tell what mitosis is.
One nucleus becomes two nuclei
19. Tell what happens to the chromosomes in interphase. Chromosomes replicate.
20. Tell what happens in prophase.
Sister chromatids become visible.
21. Tell what happens in metaphase.
Sister chromosomes line up.
22. Tell what happens in anaphase.
Sister chromatids separate.
23. Tell what happens in telophase.
Cytokinesis starts, nuclear membranes form.
24. Tell what replication is.
chromosomes duplicate identically.

#17......DNA's Shape........................Due 2/16
Print and cut out the pieces to this activity.
Activity information:

Copy the following notes.
1. Each piece of DNA is called a chromosome
2. Chromosomes contain hereditary information.
3. Genes are one instruction on a portion of a chromosome.
4. DNA is a long thin molecule with the shape of a twisted ladder.
5. The sides of the DNA molecule's ladder shape are made of alternating sugar and phosphate molecules.
6. The steps of the DNA molecule's ladder shape are made of molecules called nitrogen bases.
7. Two nitrogen bases make up each step of the DNA molecule's ladder shape.
8. A pair of bases make up each step of the DNA molecule's ladder shape
9. Base pairs are indicated by the letters A, C, G, and T.
10. A always pairs with T and C always pairs with G to make up the steps of the DNA molecule's ladder shape.

#16 Focus Items and Mitosis Activity
Copy the following:
Analogy comparing DNA to socks.
Socks – DNA
1. 23 pairs of socks – humans have 23 pairs of chromosomes
2. Females have 23 identical pairs of socks – Females have 23 homologous autosomes
3. Males have 22 identical pairs and one mismatched pair of socks – Males have 22 homologous and non-matching pair of sex chromosomes.
4. Two sock dances – DNA moves into new cells in two ways.
5. Sock yarn – Each long piece of DNA in the nucleus is a chromosome.
#16 Focus Items
Socks – DNA Analogy
6. Yarn knitted into socks as the dances start – DNA coils around proteins to form chromosomes at the start of mitosis and meiosis.
7. The My Toe-Socks Dance and the My Oh-Sock Dance – Mitosis and Meiosis.
8. A duplicate set of socks is made before each dance – chromosomes are replicated during interphase before mitosis or meiosis.
9. Cloths pins connect copied socks – Centromeres connect replicated chromosomes as sister chromatids.

Mitosis Paper Model Activity

Answer these questions after doing the activity.
10. How many pairs of chromosomes are found in human cells?
11. What is the relationship between chromosomes and genes?
12. What is the relationship between genes and DNA?
13. What is the function of the kinetochore?
14. How does the cell prepare for cell division during interphase?
15. Over all what happens during mitosis?
16. What is the main activity of telophase?
17. What is accomplished by the activity of cytokinesis?
18. How do sister chromatids compare?
19. How do homologous chromosomes compare?

#15......Sorting Chromosome Figures...........2/10
Draw the figures and include the associated text.
Pay attention to the blue and red chromosomes and make them different colors.
(Parts A, B, C, D, and E)

A. Comparing Mitosis and Meiosis
B. Genetic Variation - Mixing it up.
C. More Genetic Variation - Crossing Over
D. Chromosomes are DNA plus Protiens.
E. Define diploid and haploid used in A.

#14......Gelada Baboon and Old World Monkey Facts......2/6/2009
List facts about Gelada baboons. (that are not true baboons)
Explain old world monkeys.
Why are Gelada's not true baboons?
Contrast the social behaviors of Gelada's to mustangs.
Compare Gelada social behavior to the social behavior of wild horses.

#13......Chromosomes as Socks..........................2/5/2009

Chromosomes can be compared to socks because they come in pairs. Chromosomes are moved from an old cell to new cells in two ways. One way is called mitosis and the other is meiosis. If socks are used as a model for chromosomes, then chromosomes do two different dances. (Ones socks move while dancing.) The mitosis “dance” is how things grow and repair, while the meiosis “dance” involves genetic variation and must be understood for the breeding of animals and plants. Understanding meiosis is important for social reasons like how two brown eyed parents can have a blue eyed child. Understanding meiosis is also important for economic reason, like breeding plants and animals. In fact there might well be a food shortage in the United States today if it were not for the success in breeding crop plants for higher yields over the past 100 years. Before we can learn these two “dances” we have to get to know the “socks” or in other words the chromosomes.

For this activity, cut out these socks and put them in matching pairs from longest to shortest. Compare your sorted socks to the picture (karyotype) on page 100. Glue your pairs of socks on a sheet of paper from longest to shortest. Put the mismatched pair at the end. Read page 100. Explain the reason for the mismatched pair of socks in this activity.

Right click and print this picture.
Cut out the socks.
Glue them to a sheet of paper in matching pairs from longest to shorest.
Put any mismatched socks as a pair at the end.

#12......Meiosis and Cell Division...........2/5
Copy these notes:
1. In sexual reproduction, the genetic information of one parent is combined with that of the other parent.
2. Each parent has two copies of each chromosome that came from their parents.
3. If cells from each parent simply combined the off spring would have four copies
4. Meiosis is the process of making sex cells with only one copy of each chromosome instead of the normal two copies.
5. Meiosis - a special form of cell division in which the number of chromosomes is reduced by half, so there is only one of each kind.
6. Any cell that contains two complete sets of chromosomes is called diploid cell. Most cells are diploid.
7. A cell with only one complete set of chromosomes is called a haploid cell. Sex cells or gametes are haploid.
8. In humans, a diploid cell with 46 chromosomes undergoes meiosis to yield four haploid cells with 23 chromosomes each.
9. Draw figure 3 on page 98 and include the caption.
10. Draw the phases of meiosis on page 106 and 107. Then add items below as captions to the appropriate phase.
Meiosis Phases:
Prophase I
the replicated pairs of homologous chromosomes condense and attach to each other.
Metaphase I
The spindle fibers arrange the homologous chromosome pairs in the middle of the cell.
Anaphase I
The spindle fibers separate the homologous pairs and pull them to opposite poles of the cell.
Telophase I
Cytokinesis takes place, resulting in two haploid cells. Each chromosome in the haploid cells consists of two sister chromatids.
Prophase II
Spindle fibers from again, and chromosomes condense once more.
Metaphase II
Spindle fibers align chromosomes along the center of the cell.
Anaphase II
Sister chromatids are separated and pulled to opposite poles of the cell.
Telophase II /Haploid Cells
Cytokinesis produces four haploid cells.

#11......Mitosis Lab....................................2/5/2009
Mitosis Pictures like the ones that were required.
Draw: Interphase, prophase, metaphase, telophase and two daughter cells.

#10......Focus Items/Participation................2/6/2009

#9......Cell Cycle, Mitosis, and Chromosome Questions.....2/4/2009
Use your textbook or the two diagrams from assignment 6 below to answer the questions.
Mitosis Questions
1. Chromosomes are in what form during interphase?
2. Chromosomes are in what form at the start of mitosis?
3. Chromosomes are in what form at the end of mitosis?
4. When are the chromosomes replicated?
5. Process by which a nucleus divides into two nuclei is called?
6. Step where chromatid pairs become visible and spindle fibers form?
7. Step where chromatid pairs line up across the center of the cell?
8. Step where the chromatid pairs are separated?
9. Step where the cytoplasm begins to be divided?
10.What happens to the chromosomes during interphase?
11. What is mitosis?
12. What happens to the chromosomes in prophase?
13. What happens to the chromosomes in metaphase?
14. What happens to the chromosomes in anaphase?
15. What happens in telophase?
16. When does one set of chromosomes become two?
17. When do chromosomes condense and coil into chromatids?
18. When are chromatids organized for separation with attached spindle fibers going to each end of the cell?
19. When do the spindle fibers pull sister chromatids away from each other to opposite ends of the cell?
20. When does a cell plate form in plant cells and the cell membrane pinch in the middle like a string around a balloon in animals cells?

#8......Kangaroos and Marsupials.................Due 1/30/2009
Provide 24 facts on Marsupial characteristics, kangaroos, dingos, and platypus.

#7......Karyotyping Activity...........................Due 1/30/2009
Karyotyping Activity Sheet
Select activity link above for more information.

#6 Forms of DNA and Stages of Mitosis
Copy the diagrams. The mitosis diagram is also on page 99 in the textbook.
Mitosis Stages

#5 Focus Items/Participation.............Due 1/30
Focus items are to be done the first and last 5 minutes of the hour.
These items are collected at the end of the week, so have a spot to keep your science papers in the folder your bring to class each day.
If you don't work on these items at this time you will lose the points.
Absent students or students that lose their work must do extra credit to make up these points.

#4......Panda...........................................Due 1/23
Giant Panda and Red Panda - 28 Facts

#3......4-1 Topics and Details...................Due 1/27
Page 97 to 102
Write the page and paragraph number for the topic and details of each paragraph.
Write down the topic of each paragraph after reading it.
List the details that support the topic of the paragraph you just read.
Number the supporting details.
97/1 97/2 97/3 98/1 98/2 98/3 98/4 98/5 98/6 100/1 100/2 100/3 101/1 101/2 101/3102/1 102/2

#2......Cell Division Ideas.........................Due 1/23
1. Importance of Cell Division: Give four facts.

2. Do the Surface area activity on page 105.
Part2 ..........Surface Area ..............................................Volume
................A. 6 x _ x _ = _............................................ _ x _ x _ = _
................B. 6 x _ x = _ .............................................._ x _ x _ = _
................C. 64 x _ x _ x _ = _ ...................................64 x _ x _ x _ = _

Part 3 Ratios:
B (reduce)
C (reduce)

Part 4
The ratio for B while the ratio for C is .......
6/1 divided by 3/2 = .......
This means that C has.......times the surface area per unit of volume as compared to B.

3. Draw a figure showing the Cell Cycle p.97
Part 1: Cell grows and functions, organelles duplicate (G1)
Part 2: DNA is copied (replicated). Chromosome duplicate. (S)
Part 3: Cell grows and prepares to divide (G2)
Mitosis- nucleus divided by prophase, metaphase, anaphase, and telophase
Cytokinesis – the cytoplasm divides resulting in two cells.
Bonus: Play the game at this link.

#1......4th Chapter Two Column Vocab......Due 1/21
In one column, write the book's definition. In the second column rewrite the definition a different way without changing the meaning.