Unit Test II - Study Guide PDF

Unit Test II - Study Guide Chapters 6-10 – 100 Points Chapter 6 & 7- KNOW THE FOLLOWING 1. What is cancer and how does it start? Unregulated cell division TUMOR: mass of cells with no function Starts when tumor invades surrounding tissue 2. Differences between benign, malignant and...

Unit Test II - Study Guide Chapters 6-10 – 100 Points Chapter 6 & 7- KNOW THE FOLLOWING 1. What is cancer and how does it start? Unregulated cell division TUMOR: mass of cells with no function Starts when tumor invades surrounding tissue 2. Differences between benign, malignant and metastasis. Benign tumor: does not affect surrounding tissues, is Not cancerous Malignant tumor:Invades surrounding tissues: is cancerous Metastasis: cells break away from a malignant tumor and start another tumor in another part of the body 3. How do cancer cells differ from normal cells -Divide when they shouldn’t -Invade surrounding tissues -move to other locations in the body 4. Possible risk factors for cancer and what the terms carcinogen and synergistic stand for Risk Factors-Condition or behavior that increases the likelihood of developing a disease Carcinogens-any substance that can increase your risk of developing certain types of cancer Synergistic-enhance the activity of other carcinogens(tobacco+alcohol) Together both tobacco and drinking alcohol have a greater risk than each activity alone. 5. The steps involved in DNA replication and the enzymes involved 6. Differences between unreplicated chromosome and replicated chromosome 7. Cell cycle diagram and “Cancer, DNA and cell cycle HW” 8. Purpose of mitosis Produces genetically-identical daughter cells(M phase of the cell cycle) for asexual reproduction or to make more body cells Prophase,Metaphase,Anaphase,Telophase 9. Phases of mitosis with one or two major events that happen in each stage (may need to draw!)  10. DNA checkpoints along with the purpose of tumor suppressor genes and oncogenes G1 checkpoint: a. Are growth factors present? (Tells the cell to divide) b. Is the cell large enough and does it have enough nutrients? G2 checkpoint: c. Has DNA replicated properly? Metaphase checkpoint: d. Have all chromosomes attached properly to microtubules? Tumor suppressors genes: proteins that inspect newly replicated DNA 11. Multiple mutations hypothesis for cancer It takes MULTIPLE MUTATIONS in a SINGLE CELL in order for that cell to become cancerous 12. Basic understanding of cancer detection and treatment Chemotherapy: chemicals that selectively kill dividing cells Combination of different drugs used a. Interrupts cell division in different ways b. Helps prevent resistance to the drugs Normal dividing cells are also killed (hair follicles, bone marrow, stomach lining).  Radiation therapy: use of high-energy particles to destroy cancer cells c. Damages their DNA so they can’t continue to divide or grow d. Usually used on cancers close to the surface e. Typically performed after surgical removal of tumor 13. Purpose of meiosis Meiosis = cell division in gonads to produce gametes (sperm, egg) Reduces the number of chromosomes in each by one-half. Gamete gets one of each pair Gametes considered haploid 4 daughter cells NOT genetically identical to each other OR to the parent cell! Happens in 2 stages (see meiosis cell cycle)  14. Review HW “Meiosis Worksheet” and “DNA and Mitosis Quiz” 15. What is crossing over and when does it occur? How are homologous chromosomes involved? Crossing over: exchange of equivalent portions of chromosomes between members of a homologous pair during Prophase I. a. Results in new types of gametes being formed 16. Results of random alignment Random alignment: the way in which different pairs of chromosomes align and get separated during metaphase I is random. a. Results in different types of gametes being formed. 17. Results of nondisjunction Nondisjunction: failure of homologous pairs to separate normally during meiosis I a. Results in a gamete having one too many chromosomes (trisomy) or one too few chromosomes (monosomy) b. Most embryos that result from such gametes will die before birth c. But, several chromosome abnormalities are known in humans 18. Compare and contrast the results of mitosis and meiosis Chapter 8- KNOW THE FOLLOWING 1. Human life cycle Adults produce gametes in their gonads by meiosis. Sperm cells fertilize egg cells to form single-celled zygotes. Repeated cell divisions form the embryo.  The embryo grows to become a fetus. After birth, the individual continues to grow until reaching adulthood. 2. What is a chromosome, gene, and allele? Genes are segments of DNA that code for proteins Chromosomes are analogous to pages in the instruction manual. a. Each “page” contains thousands of “words” (Each chromosome contains thousands of genes) Different types of cells use different words, in different orders (Different types of cells use different genes in different combinations to perform different functions.) ​Mistakes in copying DNA (mutations) produce different versions of genes (alleles), with different results. 3. Know the 5 ways that we produce genetic diversity in offspring and a little about each. Random Mutations Crossing Over during Prophase I of Meiosis Segregation of chromosomes during Meiosis.: in meiosis, one member of each homologous pair separate into a gamete Independent Assortment of chromosomes during Meiosis.:randomly determines which member of a pair of chromosomes goes into a gamete Random Fertilization: produces more diversity: 64 trillion possibilities! 4. Know the difference between monozygotic and dizygotic twins Monozygotic twins are formed by one sperm and one egg. Dizygotic twins are formed by two different sperm and two different eggs. 5. Be familiar with the following terms… phenotype, genotype, dominant, recessive, homozygous, and heterozygous. Phenotype: physical traits of an individual Genotype: description of the alleles for a particular gene in an individual a. Homozygous (-ote): both alleles for a gene are identical b. Heterozygous (-ote): the gene has two different alleles Recessive: the phenotype of an allele is seen only when homozygous Dominant: the phenotype is seen when homozygous or heterozygous 6. Know how to perform simple dominant and recessive genetic crosses (examples include cystic fibrosis(recessive) and Huntington’s disease(Dominant) in humans). 7. How to perform the following genetic crosses… a. Incomplete dominance: two copies of the dominant allele are required to see the full phenotype; heterozygote phenotype is intermediate to the homozygotes (e.g., flower color in snapdragons) b. Codominance:: neither allele is dominant to the other; heterozygote shows both traits at once (e.g., coat color in cattle) c. Multiple allele (blood crosses)  d. Sex-linked Sex-linked genes: genes located on the sex chromosomes e. X-linked: located on the X chromosome f. Y-linked: located on the Y chromosome Males always inherit their X from their mother Males are more likely to express recessive X-linked traits than females Only females can be carriers of X-linked recessive traits. 8. Sex Determination Humans have 22 pairs of autosomes and one pair of sex chromosomes a. Women: two X chromosomes b. Men: one X and one Y chromosome c. The X chromosome contains many genes essential for development The SRY region of the Y chromosome contains a gene that encodes a testis-determining factor (TDF). This gene must be present for male sexual development in the embryo to begin. An XY individual could develop as a female if this gene has a mutation resulting in no functional TDF being produced.  9. Review the “Active Learning Notes” ie Ch. 8 Genetics Assignment completed in class and at home. 10. Be familiar with the term pedigree and be able to answer questions like those on the pedigree assignment. Chapter 9 – KNOW THE FOLLOWING 1. What is a quantitative trait? Quantitative traits show continuous variation: a. Large range of phenotypes b. E.g., height, weight, intelligence Variation due to both genetic and environmental differences 2. What is a polygenic trait?  Traits that are influenced by more than one gene are called polygenic traits. a. Result of three or more genes b. Each with more than one allele c. Results in numerous genotypes/phenotypes. d. Ex. human eye color 3. How are each of the following used to determine heritability… correlation studies and twin studies. ▪Heritability: proportion of the variation due to genetic differences among individuals 4. Know what the term epigenetics stands for? (Video) Chapter 10 – KNOW THE FOLLOWING 1. What is genetic engineering? Alteration of hereditary traits by molecular techniques (level of the DNA) One or more genes may be modified Genes may be moved from one organism to another There is controversy over genetic engineering surrounding ethics, use in food sources, and humans 2. The process of protein synthesis in detail (includes transcription and translation) ☺  Protein synthesis – the process of using instructions carried on a gene to create proteins. Several steps are involved and require both DNA and RNA. a. Gene – a sequence of DNA that codes for a protein b. Protein – a large molecule made up of amino acids Transcription occurs in the nucleus. c. RNA polymerase binds to the promoter region of the gene. d. RNA polymerase zips down the length of gene, matching RNA nucleotides with complementary DNA nucleotides 3. Differences between DNA and RNA DNA a. Double-stranded b. Each nucleotide composed of deoxyribose, phosphate, and nitrogenous base c. 4 bases: adenine, thymine, guanine, cytosine  RNA d. Single-stranded e. Nucleotides comprised of ribose, phosphate, and nitrogenous base f. 4 bases: A, C, G, and Uracil 4. Look at the “Review of Transcription and Translation” lecture activity 5. What is a mutation and how can it disrupt the end product of protein synthesis (the protein)! Changes in genetic sequence = mutations Changes in genetic sequence might affect the order of amino acids in a protein. a. Protein function is dependent on the precise order of amino acids b. Possible outcomes of mutation: 1 - no change in protein (neutral mutation) 2 - non-functional protein 3 - different protein (good or bad) 6. Why are all cells types in the human body different if they all have the same DNA? Each cell in your body (except sperm and egg cells) has a full set of DNA. But, each cell only expresses a small % of genes. a. Ex: Nerve and muscle cells perform different functions, thus they use different genes. b. Turning a gene or a set of genes on or off = regulating gene expression c. Only mutations found in genes that are turned ON in a certain cell will be noticable. 7. What are recombinant proteins and how are they created (all steps) rBGH is a protein, and is coded by a specific gene. Need: Restriction enzymes – Cut DNA at specific sequences. Allow scientists to make precise cuts in DNA. Plasmid – Small, circular piece of bacterial DNA. Can act as a ferry to carry a gene into a cell.  8. Pros and cons of genetically modified food 9. Transgenic organisms Transgenic organism – the result of the incorporation of a gene from one organism to the genome of another. Also referred to as a Genetically Modified Organism (GMO). 10. Stem cells undifferentiated cells, capable of growing in to many different kinds of cells and tissues. Stems cells might be used to treat degenerative diseases such as Alzheimer’s or Parkinson’s, multiple sclerosis, or liver, lung, or heart disease. Stem cells could also be used to grow specific tissues to treat burns, heart attack damage, or replacement cartilage in joints. Study - Additional genetics problems that were for extra credit GOOD LUCK STUDYING!!