Unit 6 Cell Growth and Reproduction

Transcription

1 Unit 6 Cell Growth and Reproduction Standards Addressed BIO B Describe the events that occur during the cell cycle: interphase, nuclear division (i.e. mitosis or meiosis), cytokinesis. BIO B Compare the processes and outcomes of mitotic and meiotic nuclear divisions. BIO B Describe process that can alter composition or number of chromosomes (i.e crossing-over, nondisjunction, duplication, Essential Questions How do new cells arise from the division of pre-existing cells? How do organisms live, grow, respond to their environment, and reproduce? How are the characteristics of one generation passed to the next? How and why do organisms interact with their environment and what are the effects of these interactions? How can there be so many similarities among organisms yet so many different kinds of plant, animals, and microorganisms? 7 1

2 Cell Division and the Cell Cycle Cell division is the process where cell, called the cell, divides to form new cells referred to as cells. Eukaryotic cells are more complicated since they have multiple and many other. All of these cell parts must be and then when the cell divides. Cell division in Prokaryotes Prokaryotic cells divide by. Place the number of the step in the appropriate place on the diagrams above. 1. DNA Replication 2. Chromosome Segragation 3. Separation Explain the events that occur in each of these steps DNA Replication Chromosome Segration Separation 2

3 Cell Division in Eukaryotes Before an eukaryotic cell divides, the in the cell must be replicated. Its organelles are also. The actual cell division occurs in two major steps. The first step is where the of the cell divides. The second step is where the divides and daughter cells form. The Cell Cycle Define the cell cycle Eukaryotic cell cycle Mitotic phase includes and. Explain what occurs during this phase in the space below. Interphase includes three phases, and. It is the longest phase of mitosis. G1 is the. Explain what happens during this phase below. 3

4 S Phase is the phase. What occurs in this phase? G2 is the. This is also known as 2. What happens in this phase? Control of the Cell Cycle The cell cycle is controlled mainly by. They signal the cell to either or the next phase of the cycle. These proteins ensure the cell completes the phases as needed before they move on to the next phase. There are a number of main. State what happens and where in the cycle these checkpoints occur. The G1 Checkpoint - The S checkpoint The mitotic spindle checkpoint Cancer and the Cell Cycle Cancer is described as a disease that occurs when. What may not cause this cell cycle regulation to occur? What is a tumor? 4

5 Explain the major steps in each checkpoint by writing in the box. Complete the chart below explaining how cell division in prokaryotes and eukaryotes differ. Prokaryotes Eukaryotes Number of steps in cycle Number of chromosomes Nucleus present (Yes or No) 5

6 Chromosomes and Mitosis Chromosomes Chromosomes are coiled structures made of and. Chromosomes are the form of the genetic materials during. When the DNA is not coiled, it is called. Chromatids and the Centromere DNA condenses after it has been. Each chromosome consists of identical copies and these copies are called. They are attached to each other at a. Chromosomes and Genes The DNA in a chromosome is coded with instructions for making and they are organized into units called. Most contain the instructions for a single protein. Human Chromosomes Each human has sets of chromosomes, one from each parent. Humans have a total of single chromosomes or pairs of chromosomes. Each pair of chromosomes of the same size and and contain the same genes. The pair of chromosomes is known as. Mitosis and Cytokinesis During mitosis, the two chromatids for each chromosome from each other and move to poles of the cell. Mitosis occurs in four phases,,,, and. Describe what occurs in each phase of mitosis: Prophase 6

7 The spindles start to form during prophase. on the spindle attach to the centromeres of sister chromatide. Metaphase Anaphase Telophase Cytokinesis is the stage of cell division. During this phase, the cytoplasm splits in and the cell. Draw a diagram of a chromosome with the centromere. label chromatids and centromere. If a cell skipped metaphase during mitosis, how might this affect the two daughter cells? 7

8 Amoeba Sisters Video Recap of Mitosis: The Amazing Cell Process That Uses Division to Multiply 1. Mitosis is done by your body cells. This cartoon illustrates an exception. What types of cells do not undergo mitosis? 2. Describe how mitosis is important for your body. 3. This illustration is trying to demonstrate something that mitosis is not. In mitosis, the cells that are created are 4. Mitosis is just one small part of the cell cycle! Describe what would occur if cells were in mitosis more than they were in interphase. 5. When cells are dividing, it is important to understand that they have to move chromosomes equally to both cells. Based on this illustration, describe what a chromosome is made of. 6. Mitosis starts and ends with diploid cells. That means they have two sets of chromosomes (both parents each contribute a set). In humans, how many chromosomes should be in each of these diploid cells after mitosis? 8

9 Sketch the Mitotic Stages Directions: We encourage you to be creative with a cartoon illustration of your own for each phase. Label the chromosomes, spindles, and nucleus (if applicable). Prophase Metaphase Anaphase Telophase 9

10 Reproduction and Meiosis Reproduction: Sexual vs. Asexual Reproduction is Asexual Reproduction Asexual reproduction involves a parent. The offspring are genetically to each other and to the parent. There are different methods of asexual reproduction:, and. Describe each method of asexual reproduction and give an example of each type. Binary fission Fragmentation Budding Asexual reproduction can happen very. Explain how is this an advantage for the asexually reproducing organism? 10

11 Sexual Reproduction Sexual reproduction involves parents. Parents produce reproductive cells called that unite to form an offspring. Gametes are cells which means they contain only the number of chromosomes found in other cells. Gametes are formed in the process of. When two gametes unite the process is called. The fertilized cell is called a. The is a cell which means it has the number of chromosomes as a gamete. Meiosis Meiosis is the process that produces cells. Meiosis is a type of cell division in which the number of is reduced by. This process occurs ONLY in cells of the organism. cell divisions occur during meiosis, and a total of haploid cells are produced. The two cell divisions are called I and II. Phases of Meiosis Meiosis I begins DNA replicates during interphase. Outline the four steps of Meiosis I and describe the events in each phase. Prophase 1 Metaphase 1 Anaphase 1 Telophase 1 11

12 How many daughter cells are produced in Meiosis 1? Meiosis II Outline the four steps of Meiosis II and describe the events in each phase. Prophase II Metaphase II Anaphase II Telophase II How many cells are the result of Meiosis II? Gametogenesis The development of haploid cells into gametes are called. Male gametes are called. Female gametes are called. The process that produces mature sperm cells is called. The process that produces mature eggs cells is called. Sexual Reproduction and Genetic Variation Sexual reproduction results in offspring that are genetically. 12

13 Reasons for the genetic individuality are: Sexual Reproduction and Life Cycles The life cycle is the simplest cycle. the organism spends the majority of their life cycle as haploid gametes and as they fuse, they form a zygote. life cycle spend the majority of their lives as diploid adults. When it is time for these organisms to reproduce, they undergo to produce gametes. Can you give an example of this type of organism? Some organisms switch back and forth between diploid and haploid stages. Examples of these are plants, and some. Explain why sexual reproduction results in genetically unique offspring. 13

14 Amoeba Sisters Video Recap of Meiosis: The Great Divide 1. The purpose of meiosis is to make gametes, also known as sperm and egg cells. In humans, your body cells have 46 chromosomes. How many chromosomes are in a sperm or egg cell if, when they come together to form a fertilized zygote, there are 46 chromosomes? Write the correct number of chromosomes next to the sperm and egg. 2. Interphase must occur once before meiosis can happen. (Same thing for mitosis). What would happen if interphase didn t occur first? 3. Remember that a cell that begins meiosis has 23 chromosomes inherited from mother (one is shown in red on the right in cartoon) and 23 chromosomes inherited from father (one is shown in blue on the left in cartoon). In the process of meiosis, chromosomes begin to match up in homologous pairs. How would you know if two chromosomes were homologous? 4. Crossing over is a very important event in Prophase I of meiosis! What happens during crossing over and what is the significance? 5. Meiosis does PMAT twice! That means there is a prophase 1 and a prophase 2. There is a metaphase 1 and a metaphase 2. Etc If the cartoon below has chromosomes in the middle of the cell, how would you know whether it was in metaphase 1 or metaphase 2? 6. Meiosis does not always occur without any difficulties. Describe what occurs during nondisjunction and the effect on the resulting cells. 14

15 Can you finish the meiosis chain? Write the correct stage that comes next in each circle. Don t forget the number that comes after the stage name! Then write any details about what this stage looks like next to it. Now let s play, Which Clip Would That Be Said In? Keeping mitosis and meiosis separate in your mind can be a bit tricky. Read the following speech bubbles. Determine whether they would be correctly placed in the mitosis clip, the meiosis clip, or both by drawing a line to the correct place in the Venn diagram. Interphase occurs once before the process begins. Process ends with identical cells. Produces gametes. Produces 4 cells that each have 23 chromosomes. Crossing Over occurs. Process is important for growth and repair. 15

16 Snurfle Meiosis Name: Date: Click on Snurfle Meiosis App Click on Continue Click on Continue Click on Meiosis and Genetics Interactive and follow directions as you answer the following questions. 1. When does interphase occur? 2. What occurs during interphase? 3. Uncoiled stringy DNA is called. 4. Human cells have pieces of chromatin. 5. Half of you DNA comes from your and half from your. 6. DNA has that determines traits of an organism. 7. Different forms of a gene are called. 8. What are the 2 alleles for fur color in Snurfles and which letters represent those alleles? 9. is when DNA copies itself and it occurs during. 10. are made during Meiosis. Examples of gametes are and. 11. Meiosis occurs in divisions, Meiosis and Meiosis. 12. List the phases for Meiosis I. 13. List the phases for Meiosis II. 14. During prophase I the chromosomes and become. 15. Chromosomes that are the same size and have the same genes are called. 16. Each half of a replicated chromosome is called a. 17. Sister chromatids of a chromosome are. 18. The nucleus during prophase I. 19. Homologous chromosomes pair up during prophase I to form a. 20. During metaphase I the tetrads line up in the of the cell. 21. The homologous chromosomes split up and move toward the opposite ends of the cell during. 22. independent cells begin to form during. 23. is the division of the cytoplasm to make two new cells. 24. The 2 new cells that are formed from Meiosis I are because they contain half of the chromosome of the original cell that started meiosis. 25. At the start of Meiosis I you had 1 cell. 26. Meiosis II must take place because each of our new cells still has too much. 28. Draw the chromosomes in Meiosis I. Label the cells as diploid or haploid 16

17 29. The nucleus during prophase II. 30. In Metaphase II the chromosomes line up single file down the of the cell. 31. In the sister chromatids split up. 32. In Telophase II, daughter cells are being formed. They are called. 33. Each newly formed cell will form a around the chromosomes. 34. The chromosomes to form. 35. occurs at the same time at Telophase II. 36. At the end of Meiosis II you have made gametes (sex cells). 37. Draw and label the Meiosis summary. 38. If the gametes are produced by a female, they are called or. 39. If the gametes are produced by a male, they are called. 40. The square is a tool that is used to predict the possible offspring of a genetic cross. 41. The letters on a punnett square actually represent possible. 42. When sperm and egg join it is called. 43. A fertilized egg is called a. G g 44. Complete the punnett square to the right. G 45. A is the genetic make-up of an organism. 46. Give examples of genotypes. g 47. A is the characteristic or appearance of the organism. 48. Give examples of phenotypes. 49. Dominant alleles are represented by letters. 50. Recessive alleles are represented by letters. 51. alleles will show in your phenotype even if it only has one copy. 52. For recessive traits to show in the phenotype the snurfle will need copies of the gene. 53. means an organism has 2 copies of the same allele in its genotype (GG, gg) 54. means an organism has 2 different alleles in its genotype (Gg, Tt, Rr) Click on The Chromosome Quandary and follow the directions Click on The Meiosis and Genetics Quiz! Answer the questions. Click on Score Sheet. Record Scores. Overall Score: Meiosis and Genetics: Chromosome Quandary: Quiz: Teacher s Initials: 17

18 Name Hr Complex patterns of Inheritance - Incomplete Dominance and Codominance Genetics Problems Scientists now have a better understanding of Mendelian genetics and know that the Law of Dominance does not always hold true. There are traits when the alleles seem to share equal strength in organisms, which is call incomplete dominance, where a blend or the trait will be seen. Other times, both alleles for a trait will be seen, which is called codominance. When an organism has incomplete dominance, neither of its alleles is dominant over the other. Instead the alleles are equal strength so to speak. The phenotype of the heterozygous offspring will be seen as a blend of the trait being tested. 1. In four o clock flowers, there is incomplete dominance; (RR) is the symbol for red coloration, and (R + R + ) is the symbol for yellow coloration. Cross a red male flower with a yellow female flower. Color each square the color of the flowers produced. Write the genotype for the male flower. Write the genotype for the female flower Write the phenotypic ratio of the offspring 2. In four o clock flowers, there is incomplete dominance; (RR) is the symbol for red coloration, and (R + R + ) is the symbol for yellow coloration. Using the offspring from problem one, cross an orange male flower with an orange female flower. Color each square the color of the flowers produced. What is the genotype symbol for the male flower? What is the genotype symbol for the female flower? Genotypes of offspring Description of the offspring? Genotypic ratio = 3. Now cross a homozygous male red flower using a heterozygous female offspring from problem one. Color each square the color of the flowers produced. What is the genotype symbol for the male flower? What is the genotype symbol for the female flower? Genotypes of offspring 18 Description of the offspring?

19 In some complex inheritance pattern, heterozygous organism will express or show both alleles for a trait. When both alleles for a trait can be seen the organism is called codominant. 1. In cattle coloration there is a codominance; (R) is the symbol for red hair, (W) is the symbol for white hair, and (RW) is the symbol for roan. Cross a homozygous red male with a homozygous white female. What is the genotype symbol of the male? What is the genotype symbol of the female? Genotypes of offspring Phenotypes of offspring 2. In cattle coloration there is a codominance; (R) is the symbol for red hair, (W) is the symbol for white hair, and (RW) is the symbol for roan. Now cross a heterozygous roan male with a homozygous white female. What is the genotype symbol of the male? What is the genotype symbol of the female? Genotypes of offspring Phenotypes of offspring 3. Now cross a heterozygous roan male with a heterozygous roan female. What is the genotype symbol of the male? What is the genotype symbol of the female? Genotypes of offspring Phenotypes of offspring Moo 19

20 Mutation Activity: What can happen when things go wrong? Objectives: - To demonstrate the processes of transcription and translation. - To demonstrate how the three types of mutations occur (insertion, deletion, and substitution). - To demonstrate the effects of the three types of mutations on the amino acid chain produced by a DNA strand. Background: The genetic makeup of all known living things is carried in a genetic material known as DNA. The bases pair very specifically (A only with T and C only with G) so that when the DNA molecule replicates every cell has an exact copy of the DNA strand. The order of the bases in a DNA molecule is the key to the genetic code of an individual. Every three bases are known as a codon and codes for an amino acid. Proteins are made up of amino acids and the order of them determines the protein made. In this way the order of the bases in the DNA molecule determines which proteins are made. DNA is found in the nucleus of the cell, but proteins are made in the ribosomes in the cell cytoplasm. The mrna molecule is used to carry the message from the DNA molecule in the nucleus to the ribosome in the cytoplasm. RNA is very similar to the DNA molecule except that the base T is replaced with the base U and RNA is single stranded (one half of the ladder). At the ribosome, another type of RNA (trna) transfers amino acids from the cytoplasm to the growing amino acid chain at the ribosome. BUT, sometimes there are problems with the DNA molecule that result in a change in the order of bases. This is known as a mutation and there are three different types. 1) Deletion: a mutation where a base is left out. 2) Insertion: a mutation where an extra base is added 3) Substitution: a mutation when an incorrect base replaces a correct base. There are three possible outcomes when DNA sequences change: 1) An improvement 2) No change at all 3) A harmful change 20

21 Codon Chart First Base Second Base U C A G Third Base U Phenylalanine Serine Tyrosine Cysteine U U Phenylalanine Serine Tyrosine Cysteine C U Leucine Serine Stop Stop A U Leucine Serine Stop Tryptophan G C Leucine Proline Histidine Arginine U C Leucine Proline Histidine Arginine C C Leucine Proline Glutamine Arginine A C Leucine Proline Glutamine Arginine G A Isoleucine Threonine Asparagine Serine U A Isoleucine Threonine Asparagine Serine C A Isoleucine Threonine Lysine Arginine A A (start) Methionine Threonine Lysine Arginine G G Valine Alanine Aspartate Glycine U G Valine Alanine Aspartate Glycine C G Valine Alanine Glutamate Glycine A G Valine Alanine Glutamate Glycine G 21

22 Mutation Activity: What can happen when things go wrong? In this lab you will determine the protein for a normal strand of DNA and then the protein if each of the three types of mutations occurs for that particular strand of DNA. Procedures: 1. The following is a strand of DNA that a protein will be made from. Write the transcripted mrna in the spaces below it. 2. G A C G C C A T G G A A G T C Draw a line between each codon. 5. Look up the amino acid for each codon on the codon chart and write them in the spaces below. Be sure to do this in order. This is the normal protein The following is the same strand of DNA but with a deletion mutation in the second codon. Write the transcripted mrna in the spaces below it. 8. G A C G C A T G G A A G T C Draw a line between each codon. Do you see any differences between the codons on this mutated strand and the normal strand? Describe them. 11. Look up the amino acid for each codon on the codon chart and write them in the spaces below Was the number of amino acids the same as the original strand? 14. How many of the amino acids were the same as the original strand? 15. How many of the amino acids were different from the original strand? 16. Do you believe that this mutated DNA strand would create the same protein or a different protein as the original? Why? 22

23 17. The following is the same strand of DNA but with an insertion mutation in the third codon. Write the transcripted mrna bases below it. 18. G A C G C C A T A G G A A G T C Draw a vertical line between each codon. Do you see any differences between the codons on this mutated strand and the normal strand? Describe them. 21. Look up the amino acid for each codon on the codon chart and write them in the spaces below Was the number of amino acids the same as the original strand? 24. How many of the amino acids were the same as the original strand? 25. How many of the amino acids were different from the original strand? 26. Do you believe that this mutated DNA strand would create the same protein or a different protein as the original? Why? 27. The following is the same piece of DNA but with a substitution mutation in the first codon. Write the transcripted mrna bases below it. 28. G A A G C C A T G G A A G T C Draw a vertical line between each codon. Do you see any differences between the codons on this mutated strand and the normal strand? Describe them. 31. Look up the amino acid for each codon on the codon chart and write them in the spaces below Was the number of amino acids the same as the original strand? 34. How many of the amino acids were the same as the original strand? 35. How many of the amino acids were different from the original strand? 36. Do you believe that this mutated DNA strand would create the same protein or a different protein as the original? Why? 23

24 Amoeba Sisters Video Recap of Mutations: The Potential Power of a Small Change Note: You will need an mrna chart for many of these questions. If you don t have one, they are easy to find online with your favorite search engine. 1. Mutations can be harmful, helpful (unlikely), or neutral in their effect. Often a neutral mutation will not change the amino acid that it codes for. Using your mrna chart, give another mrna codon that this CUU could mutate to and still code for Leucine. 2. It is important to understand that in mutations, a specific part of a nucleic acid experiences the mutation. In the below cartoon, fill in the blank that describes the part of the DNA molecule that is experiencing the mutation. Then label where that part is found on the DNA in the picture below. The mrna codon CUU could mutate to C and still code for Leucine, which could be a neutral mutation. 3. Even a gene mutation that is a point mutation, meaning it affects one nucleotide base, can still make a major change. Sickle Cell Anemia is caused by a point mutation knows as a substitution. Complete the following example of a substitution: If the following is for normal hemoglobin: 4. An insertion or deletion can result in a frameshift mutation. To demonstrate this, complete the following: Normal Strand: DNA: GCA ATG CAC mrna: Amino Acids: Deletion (causing a frameshift): Taking out the first G in the original DNA above results in: Show what would occur if the first T ( thymine ) DNA base in the portion shown above mutated to an A ( adenine ). Sickle Cell Hemoglobin: Portion of mutated hemoglobin DNA: mrna: Amino Acids: DNA: CAA TGC AC mrna: Amino Acids: How did the frameshift change the amino acids that were coded? 24

25 For the following, place an X if it is true statement. What do you remember about mutations? Mutations are random. Mutations can occur in both DNA and RNA. Not all DNA codes for proteins. Mutations are mostly beneficial and useful for an organism. Mutations can only occur during interphase. Not all genes are turned on or activated. Substitution mutations typically result in frameshift. Mutations can be genetically inherited. Illustrate That Chromosome Mutation Sketch your own cartoon for the following chromosome mutations. Creativity is encouraged! Duplication Deletion Inversion Translocation 25

26 Name: TOPIC 6: DNA and its processes Please use the Council Rock Video Podcast to guide you 1. Label the three parts of a nucleotide to the right. 2. DNA has strands and the bases denine, ymine, tosine, and uanine. 3. RNA has strand and the base racil instead of thymine. 4. What are the functions of mrna? trna? rrna? 5. What are the three different processes that nucleic acid can do? a. b. c. 6. What happens during replication? 7. What happens during transcription? 8. What does AUG code for? 9. What do UGA, UAA, and UAG code for? 10. What happens during translation? 11. What is the biology definition of a mutation? 12. What happens during a. Substitution mutation b. Insertion point mutation c. Deletion point mutation d. Duplication chromosomal mutation e. Deletion chromosomal mutation f. Inversion chromosomal mutation g. Translocation chromosomal mutation 26