Unit 4 REVIEW THE RELATIONSHIP BETWEEN GENES DNA

Unit 4 REVIEW • THE RELATIONSHIP BETWEEN GENES, DNA, CHROMOSOMES. • PARTS OF THE DIVIDING CELL & CELL CYCLE • CELL DIVISION= MITOSIS vs MEIOSIS • REPRODUCTION- Sexual vs asexual reproduction -------------------------------------- • GENETICS Mendel’s laws of heredity Patterns of inheritance Meiosis and genetic variation Non-Mendelian patterns of inheritance

CELL DIVISION-All cells in living plants and animals go through cell division in order to create more cells. There are 2 types of Cell Division-MITOSIS AND MEIOSIS and they occur in the cell nucleus. At the end of each mitosis and meiosis division, the cell rests from dividing and prepares for the next division by entering the INTERPHASE or CELL CYCLE. MITOSISS MEIOSIS--Produces the sex cell, egg, sperm or gamete Starts with 2 N number of chromosomes MITOSIS Produces Body cell or Somatic cell e. g. skin cell Starts with 2 N number of chromosomes-1 male+1 female) Ends with each cell same # chromosomes (2 N) End product 2 Diploid cells w. same # chromosomes (2 N) Ends with each having ½ of chromosomes of original cell (N) End product 4 Haploid cells…w. 1/2 # chromosomes Crossover occurs as homologous chromoseomes genetic variation Associated with Mendel laws of Heredity and genetic inheritance

Labelling the Dividing cell THESE ARE THE PARTS OF THE CELL INVOLVED IN CELL DIVISION. Pp 280 + 282 Red /pp 135 Blue HMH *Cell Division whether it is Mitosis or Meiosis takes place in the Nucleus. *In the Nucleus are the chromosomes. *Chromosomes unwind like a slinky to give us DNA Letters of the bases form the genes proteins Cell membrane *DNA has bases=letters *DNA RNA proteins that form genes *Genes give us our traits or characteristics Centrioles

UNIT 4 -CELL DIVISION DO NOW # 1. The diagram below shows the dividing cell. (Slide 2 - pp. 282 Red) Do Now #1 Label the cell to show 1. Cell membrane. 2. Nucleus 3. nuclear membrane. 4. chromosomes made up of 5. sister Chromatids joined in the middle by 6. Centromere. 7. Centrioles or centrosomes 8. Spindle Fiber. . DO NOW #1. 1. In Iwhich cell organelle is Cell Division taking place? (Sl 2) 2. Name the 2 types of cell division- Slide 2 3. What happens when the cell is NOT DIVIDING. (Sl. 2) 4. How do you know this cell is an animal cell (pp 207 Red) 5. How is DNA and chromatids related to chromosomes. (Sl. 3) 6. How may chromatids are in 1 chromosome? Sl 3) 67 What joins the 2 chromatids together? Sl. 3 .

*THE CELL CYCLE/ INTERPHASE OCCURS IN EUKARYOTIC CELLS pp 281 -282 Red. 130 HMH Blue Video-https: //www. youtube. com/watch? v=Ys. BHu 07 j 4 Dg Answer-The CELLTHE CYCLE =Interphase. includes-G 1, S, + G 2+WHY phases. In the cell cycle/interphase the cell is EQ: WHAT ARE PHASES + EVENTSIt. OF THE CELL CYCLE IS IT IMPORTANT? In the cell cycle or Interphase the cell is not dividing but is preparing to divide by increasing DNA, proteins+ organelles. Then M-Mitosis/Meiosis or cell division occurs ending with cytokinesissplitting of the cell daughter cells. The cycle begins again. Interphase is important to ensure that the cell has enough DNA+ parts+proteins when it divides. WHAT HAPPENS IN EACH STAGE OF THE CELL CYCLE? Stage 1. -G 1 (Gap 1)-Increase in size of cell + makes new proteins +organelles Stage 2 -S-synthesis of DNA + Chromosomes; these are replicated/copied -G 2(Gap 2) –growth-More organelles +protein are produced; shortest phase. Between each stage there is a check point/signal that gives the dividing cell the OK to go to the next stage in the cycle. If the cell cannot pick up the signal it may stay in I stage too long ex. It may divide in mitosis too long cancer Afer cell cycle, Mitosis or Meiosis-Cell goes through P-M-A-T Cytokenesi. = Cytoplasm splits -Cell is divided. Interphase-starts again IN PROKARYOTIC--NO CELL CYCLE- JUST BINARY FISSION How is the cell cycle and cancer related? pp 289 *In cancer the cell is unable to pick up signals/check point to stop dividing due to a defective gene or proteins or cyclin called p 53 gene. This is a mutation = gene mutation that can cause mistakes in the DNA and genes. Therefore the check points in the cysle do not work cell continues to over-divide tumors Cancer. It is a problem with regulation of cell cycle and division continues non-stop.

MUTAGENS & EXAMPLES OF MUTATIONS. MUTAGENS=These harmful substances , chemicals, pollutants that can cause a mutation = errors in the DNA. Mutations be negative or positive. Mutations can cause the cell cycle to become out of control CANCER as in P 53 gene MUTAGENS that cause cancer are called carcinogens Mutations can interfere with the genotype (genetic make up of an organism) and cause the organisms’ phenotype (looks) to be different Harmful Mutations*e. g. Cancer-a mutation causes gene P 53 causes the cell not to pick up signals in Cell division. It does not stop dividing overproduction of cells. *Cystic fibrosis-Deletion of gene=gene mutation *Downs syndrome-nondisjunction/trisomy=chromosomal mutation *Sickle cell-mutation in hemoglobin protein-substitution Beneficial Mutationse. g. *New proteins; *Resistance to disease in plants; *resistance to pesticides in plants; *new species with adaptations

U 4 -Cell Division-Do Now #2 -The diagram shows the cell cycle…. Slide 6 1. Number and Name the stages of the cell cycle. 2. State another name for the cell cycle. = 3. Why is the Cell cycle important= 4. In each stage state what happens –you can do this on diagram-USE VERBS 5. Explain how the Cell cycle is related to cancer DO NOW #3 Which of these statements best describes the relationships among environmental influences, the gene, and cancer? A. Environmental influences can lead to mutations in the p 53 gene, which can cause certain cancers. B. Increased levels of p 53 protein, rather than environmental influences, can cause certain cancers. C. Mutations in the p 53 gene increase environmental influences that can cause certain cancers. D. Genes such as p 53 are less casual than environmental influences in stimulating certain cancers

Mitosis Meiosis pp 326 MEIOSIS--Produces the sex cell, egg, sperm or gamete Starts with 2 N number of chromosomes MITOSIS Produces Body cell or Somatic cell e. g. skin cell Starts with 2 N number of chromosomes Ends with each cell same # chromosomes (2 N) End product 2 Diploid cells w. same # chromosomes Ends with each having ½ of chromosomes of original cell (N) End product 4 Haploid cells…w. 1/2 # chromosomes Crossover occurs as homologous chromoseomes genetic variation ssociated with Mendel laws of Heredity and genetic inheritance. Meisosis is necessary to mainintain chromosome numbers in SEXUAL REPRODUCTION

MEIOSIS-PROPHASE 1 -Crossover+tetrads +chariasata In Meiosis special event *Prophase 1 *Homologous Chromosomes *Crossover *Tetrads-4 chromatids *Genetic diversity or variation *Independent assortment

DIFFERENCES BETWEEN MITOSIS AND MEIOSIS How are Mitosis & Meiosis Different pp 326 Mitosis *No. of Divisions 1 division 2 - 1 st Div. Meiosis 1 & 2 nd Div. Meiosis 2 *# of Cells + Chromosomes we begin and end with. N =chromosomes Product-What do we end up with Begin with 1 cell +End with 2 cells are Each daughter cells have the same number of chromosomes as the original. Chromosome #=same =DIPLOID=2 N Begin with 1 cell called germ cell=diploid End with 4 cells different from original-w. half # of chromosomes Chromosome #=1/2=HAPLOID=N Body Cells=somatic cells with same # chromosomes as we started with. Ex. brain, nerve, zygote (Baby cell) any cell but sex cell. Genetic diversity pp 324 No crossing over of chromosomes =no genetic diversity, cells are identical Sex cells=gametes =sperm or egg/ovum -with ½ # of chromosomes. Therefore Meiosis occurs in germs cells of the TESTES +OVARIES , Crossing over of chromosomes occur in Meiosis -prophase 1=genetic diversity Phases +Sequence PMAT=Phophase metaphase anaphase telophase. Then cytokinesis +interphase PMAT=Phophase metaphase an aphase telophase. Then cytokinesis +interphase

Using the Prompts, Complete this worksheet SEQUENCE This is the sequence of stages of mitosis +Meiosis--PMAT=Prophase, Metaphase, Anaphase, Telophase……. then Cytokinesis, , Interphase (This acronym helps-Please Make All The Classes Interesting) 1. IDENTIFY THE STAGES OF MITOSIS +MEIOSISThe location of chromosomes gives us stage P=Prophase-chromosome are pressed in center of cell. M=Metaphase-chromosomes in middle of cell A= Anaphase -Chromosome are pulling apart from middle T=Telophase chromosomes are at the Tails of cell …then Cytokenesis -the cytoplasm divides to give daughter cell Interphase=cell cycle

Organism Clue HAPLOID vs DIPLOID CELLS pp 327 body cell/ somatic 1. a gamete of a housefly has 6 chromosomes 2. a human muscle cell has 46 chromosomes 3. a leaf cell of corn has 20 chromosomes 4. a haploid cell of fruit fly has 4 chromosomes 5. a diploid duck cell has 80 chromosomes gamete haploid cell diploid cell Sperm gamete egg gamete N 2 N

The Difference Between Sexual and Asexual Reproduction pp 819 Red SEXUAL REPRODUCTION-MEIOSIS Ex. mammal reproduction, congugation in bacteria; anytime there is need for male + female sex cell, Requires 2 parents or sex cells or gametes (Sperm + egg) with haploid no. of chromosomes(N) to unite to form a zygote with diploid no. of chromosomes. ((2 N). This may be an disadvantage as time and energy are spend finding a mate Meiosis is the cell division that forms the sex cells or gametes. Sex cells join to from a genetically different cell since there is a recombination of alleles Genetic diversity occurs since 2 sets of genes-1 from each parent, are recombined=Recombination of alleles or genes. Therefore offspring look different This increases the chances of the organism evolving into a healthier and more adaptable species; increases the chances of speciation or new species forming Genetic diversity ensures, there is a lesser chance of diseases and defects seen in parents being passed on to their children. Genetic diversity leading to disease resistance in a population and new species evolving is an advantage ASEXUAL REPRODUCTION-MITOSIS Ex. Budding as in yeast fungus, Cuttings in plants, binary fission in bacteria, regeneration as in starfish, cloning, genetic engineering, See slide 15 Requires only 1 parent This may be an advantage-since less time, energy is spent finding a mate Mitosis is the cell division involved in asexual reproduction all offspring cells= same No genetic diversity occurs…. all offspring =identical. In case of natural disease all organisms can die as all are same genetic make up. This is a disadvantage

EXAMPLES OF ASEXUAL PRODUCTION-only 1 parent is needed BUDDING ex. Yeasts, fungus BINARY FISSION Ex. Bacteria divides into 2 FRAGMENTATION fungus REGENERATION SEXUAL REPRODUCTION Requires a sex cell/egg, sperm gamete. USING ANY PART OF A PLANT TO PRODUCE A NEW PLANT EXCEPT THE SEED ASEXUAL REPRODUCTION –No egg /sperm/gamte is involved; only body cells

WORD CLUSTERS MITOSIS * • • • Produces Body cell or Somatic cell e. g. skin cell Starts with 2 N number of chromosomes Ends with each cell same # chromosomes (2 N) End product 2 Diploid cells w. same # chromosomes MEIOSISProduces the sex cell, egg, sperm or gamete Starts with 2 N number of chromosomes Ends with each having ½ of chromosomes of original cell(N) End product 4 Haploid cells…w. 1/2 # chromosomes Crossover occurs genetic variation Associated with Mendel laws of Heredity and genetic inheritance

GENETICS

Vocabulary Words: Write the meanings of these words 1. Genetics + Heredity -308 2. Trait 309 3. Genes and Alleles 309 -310 4. P 1 generation; F 1 Generation (first filial) F 2 -generation(second filial) 311/312/317 5. Homozygous +Heterozygous/example 314 6. Dominant+ Recessive alleles/example 310 7. Hybrid 309/Monohybrid cross/ex. & Dihybrid cross/ex. 317 8. Genotype + phenotype /example 315 9. Multiple alleles/example -320 10. Polygenic. Traits/example-320 11. Gene Linkage & Sex Linkage 329 12. Gene mapping 329

HOMOLOGOUS CHROMOSOMES & CROSSOVER –pp 184 HMH blue Bl. Pp 324 Red see video meiosos Mc. Graw Hill Chromosomes that carry the same genes are termed homologous chromosomes (compare w. homologous structures) Homologous chromosomes cross over or mix & match genetic material during Prophase 1 of Meiosis causing genetic variation. It forms a Tetrad (4 chromatids, cross over genetic diversity=variation This is associated with Mendel’s law of segregation + independent assortment.

MENDELIAN GENETICS by Scientist Gregor Mendel PUNNETT SQUARE for Monohybrid cross bet. 2 heterozygous for 1 trait. Probability/=Ratio=3: 1 or 75% : 25% law of s ’ l e d Men gation segre alleles=Letters. Each trait is carried by 1 gene with 2 lettersupper +lower case. Genotype=Letters. Phenotype= how the organism looks P 1 and F 1 generations PUNNETT SQUARE for Dihybrid cross below Shows= 2 –traits (R +Y) Ratios 9: 3: 3: 1 =4 phenotypes-4 combinations 8 gametes and 16 offspring Mendels Law=Independent Segregation

INHERITANCE PATTERNS THAT ARE EXCEPTIONS TO MENDELS GENETICS-go against Mendelian Concepts pp 197 HMH INCOMPLETE DOMINANCE There is a blending=intermediate trait CODOMINANCE= “co” means both traits show up in 1 organism Chromosomal Disorder Chromosomes fail to split in Meiosis. Each cell should have had 2 chromosomes as in Mendel. This is nondisjunction causes =Trisomy Downs Syndrome -Chromosome #21 LE LTIP MU SEX LINKED TRAITS XX=Female sex chromosomes XY=Male sex chromosomes POLYGENIC INHERITANCE Some traits ex. height, skin color are controlled by many genes instead of 1 ALL SELE , i A, B

THE MAIN PRINCIPLES IN MENDEL’S GENETICS Video-https: //www. youtube. com/watch? v=NWqg. ZUn. Jd. AY Concept 1. Mendel says that inheritance of biological characteristics or traits is determined by factors called genes. Each trait is controlled by one gene -represented by alleles or 2 letters (Upper case +lower case) per trait. Genes are passed from one generation to another in heredity DO -Give an example of a trait ------------------- Give 2 letters for your one trait-------------__________________________________________________________ Concept 2. Mendel’s Law of Dominance states-Each individual has a gene with 2 opposite forms for each trait studied ( like Tt for height, ) where one allele/letter for the trait is dominant over the other recessive allele. These two alleles comprise the gene pair. Alleles =letters. i. DO Using your example from #1. Letters used above -----------------(2 letters) ii. DO Express the term DOMINANT ------------(1 letter) iii DO-Express the term RECESSIVE = --------(1 letter). When will an organism show a recessive trait-------- (2 letters) iv. DO-Express the genotype of HOMOZYGOUS RECESSIVE=----------------(2 letters). What is its Phenotype(looks)--------v. DO-Express the genotype of HOMOZYGOUS DOMINANT=------------(2 letters). What is its Phenotype(looks)------------vi. DO-Express the genotype of HETEROZYGOUS=------------. (2 letters). What is its Phenotype(looks)----------------vii. DO- Circle the right word-Letters represent (GENOTYPE or PHENOTYPE )how the organisms looks represent (GENOTYPE/ PHENOTYPE). __________________________________________________________ Concept 3. Mendel’s Law of Segregation- states- -Alleles /letters for each gene pair segregate into a gamete, thus each gamete only carries one letter of the gene pair. Happens in Meiosis. DO-Give an example-Draw the Punnett square- when a Homozygous Tall (using T for the allele) is crossed with Heterozygous. Concept 4. Law of Independent Assortment-Mendel. Genes for different traits segregate +sort independently of each other e. g. eye color separates independently of skin color. Happens in Meiosis-Crossover-prophase 1. Slide 19 DO Explain this slide

Exceptions to Mendel’s Laws+Concepts- Slide 20 1. INCOMPLETE DOMINANCE (blending or intermediate trait/IB). No trait is more dominant than the other as in Mendels law, dominance is incomplete or blended. DO-Example 1(Slide 20) DO-Example 2 (197 Blue HMH) ------------------------------------------------------------------2. COMINANCE (traits appear together instead of 1 dominant occurs in Mendel)) DO example Slide ----------------------------------------------------------------------3. MULTIPLE ALLELES- p. 197 hmh/slide 20 e. g. human blood cells have 3 letters/alleles instead of 2 as in Mendel’s DO example ----------------------------------------------------------------------4. POLYGENIC TRAITS e. g. skin color, height. Slide 20 DO EXAMPLE ----------------------------------------------------------------------5. SEX LINKED TRAITS e. g. color blindness, hemophilia. Slide 20 DO EXAMPLE –Explain the Punnett Square __________________________________________ 6. NON DISJUNCTION=Trisomy Down Syndrome= 401 Red. Slide 20 Explain ----------------------------------------------------------------------7. MUTATIONS- How does a mutation affect genotype and phenotype of an organisms. Slide 6

How are sex linked genes like hemophilia and color blindness transmitted through the generation? 1. Hemophilia and color blindness are carried on the recessive gene on X chromosome. 2. Because there are 2 XX in females one X dominates over the other XH , the female has less chance of being color blind or having hemophilia. 3. Men with XY chromomosme have a higher chance of being color blind or having hemophilia 4. XXh x XY=Sex Linked Color blindness or hemophilia X Xh X XX XXh Y XY Xh Y

SCIENTISTS in BIOLOGY • U 4 -Mendel, Gregor-GENETICS- +Laws of Genetics, genes, inheritance --------------------------------------------- • Hershey +Chase –DNA-Material in viruses is DNA not protein. • Franklin, Rosalind-DNA is has a shape that appears double. • Watson & Crick- DNA-based on Franklin’s Xrays confirmed that DNA has shape of a double helix. • Chargoff, Edwin-DNA-The bases AT are equal in numbers just line C+G are equal in numbers. • Linnaeus, Carolus-Taxonomy/classification of living organisms • Darwin, Charles=Theory /evolution/natural selection adaptation survival reproduction>new species/speciation.

CHARTS/DIAGRAMS probability of genotypes and phenotypes in inheritance -- 1. Punnett Squares- ---------------------------------- *Karotype(K) chromosomes pairs in organisms pp 392 *K shows Autosomes (22 pairs) + Sex chromosomes (1 pair)in humans K Can show diseases of chromosomes like Downs Syndrome =chromosomes fail to separate=non-disjunction =Trisonomy ----------------------------------*Pedigree Charts Show a trait is transmitted Thru the generations using symbols

UNIT 4 VOCABULARY-Topics-Reproduction, Cell Cycle, Cell Division, Genetics 4. 1 - asexual-reproduction, gamete, sexual-reproduction, binary- fission, geneticvariation, budding, fertilization, vegetative- propagation, cancer, carcinogen, cell- cycle, chromosomes, mitosis, mutation 4. 2 - allele & genes, genetic-cross, gamete, phenotype & genotype, dominant & recessive, gamete, Punnett -square, Independent-assortment, Segregation, homozygous & heterozygous, Mendel, Heredity , P 1 generation , F 1 Generation (first filial) , F 2 -generation-(second filial) pp. 311 -312/317 4. 3 - diploid & haploid, homologous, meiosis, crossing-over, codominance, karyotype, Incomplete-dominance, polygenic traits, genetic-disorder, pedigree, sex-linked, multiple –allele, gene-mapping

Learning Objectives -Students will be able to 4 -1: Identify relationships between cell structure and function. (SC. 912. L. 14. 3) 4 -2: Identify and describe the stages of the cell cycle. (SC. 912. L. 16. 14) 4 -3: Model the movement of chromosomes during mitosis. (SC. 912. L 16. 14) 4 -4: Explain the role of mitosis in the formation of new cells. (SC. 912. L. 16. 14) 4 -5: Relate the role of enzymes to the events that regulate the cell cycle. (SC. 912. L. 16. 14, SC. 912. L. 18. 11) 4 -6: Distinguish between the events of the normal cell cycle and those of uncontrolled cell growth. (SC. 912. L. 16. 8) 4 -7: Analyze the relationship between mutation, uncontrolled cell growth, and cancer. (SC. 912. L. 16. 8 ) 4 -8: Identify the importance of reproduction to living things. (SC. 912. L. 16. 17) 4 -9: Define asexual and sexual reproduction. (SC. 912. L. 16. 17) 4 -10: Identify that offspring produced by asexual reproduction are genetic copies of the parent. (SC. 912. L. 16. 14, SC. 912. L. 16. 17) 4 -11: Relate the process of mitosis to different types of asexual reproduction. (SC. 912. L. 16. 17, SC. 912. L. 16. 15) 4 -12: Explain that the offspring of sexual reproduction contain genetic information from two parents. (SC. 912. L. 16. 17) 4 -13: Relate the process of sexual reproduction to genetic variation. (SC. 912. L. 16. 17) 4 -14: Compare advantages and disadvantages of asexual and sexual reproduction. (SC. 912. L. 16. 17) 4 -15: Describe how Mendel conducted his experiments to study patterns of inheritance in pea plants. (SC. 912. L. 16. 1, SC. 912. N. 3. 3) 4 -16: Explain that genes exist in alternative forms called alleles. (SC. 912. L. 16. 1) 4 -17: Contrast the inheritance patterns of dominant and recessive alleles. (SC. 912. L. 16. 1) 4 -18: Calculate ratios to explain experimental data related to heredity. (SC. 912. L. 16. 1, SC. 912. L. 16. 2, SC. 912. N. 1. 1) 4 -19: Explain Mendel’s laws of segregation and independent assortment and relate them to his experiments. (SC. 912. L. 16. 1, SC. 912. N. 1. 6, SC. 912. N. 3. 3) 4 -20: Differentiate between the genotype and phenotype of an organism. (SC. 912. L. 16. 1, SC. 912. L. 16. 2) 4 -21: Predict the results of a genetic cross using Punnett squares. (SC. 912. N. 16. 1, SC. 912. L. 16. 2, SC. 912. N. 3. 5) 4 -22: Differentiate between haploid and diploid cells. (SC. 912. L. 16) 4 -23: Analyze how gamete formation and fertilization maintain chromosome number within a species. (SC. 912. L. 16) 4 -24: Summarize the events that occur during meiosis. (SC. 912. L. 16) 4 -25: Describe the processes of independent assortment and crossing over during meiosis. (SC. 912. L. 15, SC. 912. L. 16) 4 -26: Relate the behavior of homologous chromosomes during meiosis to Mendel’s laws of heredity. (SC. 912. L. 15, SC. 912. L. 16. 16, SC. 912. L. 16. 17) 4 -27: Model how meiosis results in the formation of haploid gametes. (SC. 912. L. 16) 4 -28: Explain how meiosis contributes to genetic variation within a species. (SC. 912. L. 15, SC. 912. L. 16. 17) 4 -29: Compare and contrast mitosis and meiosis. (SC. 912. L. 16. 17) 4 -30: Identify observable dominant and recessive traits in humans. (SC. 912. L. 16. 2) 4 -31: Interpret a pedigree to determine patterns of inheritance in families. (SC. 912. L. 16. 2, SC. 912. N. 1. 6, SC. 912. N. 4. 1) 4 -32: Predict the pattern of inheritance of a simple dominant trait. (SC. 912. L. 16. 1, SC. 912. L. 16. 2) 4 -33: Explain how genetic disorders can be caused by inherited recessive alleles. (SC. 912. L. 14. 6, SC. 912. L. 16. 2) 4 -34: Analyze how incomplete dominance and codominance influence patterns of heredity. (SC. 912. L. 16. 2)

UNIT 4 -CELL DIVISION 1. What is the function of the structure labeled A in the drawing. pp 282/ Slide 3 A. carry genetic information B. hold chromatids together C. anchor the spindle fibers D. pull chromatids apart B 2. What is the structure labeled B in the drawing? pp 282 / Slide 3 A. Chromatids B. spindle fibers C. centrioles D. Centromeres 3. Which of the following phrases best describes cancer? Slide 5 pp 289 A. absence of cyclins in the DNA B. uncontrolled cell growth caused by mutations in genes that control the cell cycle C. presence of genetic defects caused by hereditary disorder D. multiple gene mutations on a chromosome of DNA 4. Which process is correctly matched with the phase in which it occurs? Slide 5 pp 281 A. G 1 phase, DNA replication B. G 2 phase, organelles copied C. S phase, cell division D. M phase, cell growth 5. Mitosis, a stage in the cell cycle, is important for what reason? Slide 5 pp 281 A. reduction of the cell’s chromosome number B. removal of diseased cells C. growth and repair of an organism D. division of the cytoplasm 6. Which description best fits the activity of a cell during interphase? Slide 5 pp 281 A. the cell grows and chromosomes replicate B. the cell differentiates to have a new function C. cell splits in two, but with half the normal of chromosomes D. the cell splits in two 7. DNA replication occurs in _____ Slide 5 pp 281 A) prophase of both mitosis and meiosis C) the G 1 phase of interphase in reproductive cells only B) the S phase of interphase D) metaphase of meiosis only 8. When mutations cause a failure in the regulation of cell growth and development, what condition might occur? Sl. 5 pp 289 A. normal mitosis B. cell plates form C. cancer D. Meiosis 9. Cytokinesis refers to _____ Sl. 5 pp 282 A. division of the entire cell. B. division of the nucleus C. division of the cytoplasm 10. Where are centromeres located in cell? Sl. 3 pp 280 A. Mitochondria B. golgi apparatis C. chromatids D. centriole D. reduction in the number of chromosomes

UNIT 4 11. The diagram below shows the phases of Mitosis. Which diagram represents the anaphase? Slide 11/pp 326 A. 1 B. 2 C. 4 D. 5 12. How many chromosomes would there be in each newly formed nucleus in a human cell at the end of mitosis? Slide 10 / pp 326 A. 12 B. 23 C. 46 D. 92 13. During which phase of meiosis do homologous chromosomes align as tetrads in the middle of the spindle? Pp 324/Sl. 11 A. Prophase B. Cytokinesis C. Metaphase D. Interphase 14. What term is used to describe pairs of chromosomes for the same traits? A. Homologous B. homozygous C. heterozygous D. sex Pp 323/ Slide 18 15. Mitosis and meiosis are processes involved in cell reproduction. Pp 326. Slide 11 Which of the following describes an event that results from mitosis but NOT meiosis? A two stages of cell division C. daughter cells that are identical to the parent cell B. replication of cellular genetic material D. four daughter cells that are produced from each parent cell. 16. If a gamete of an organism has 10 chromosomes; how many chromosomes would be in each of its normal body cells? Slide 11 pp 326 A. 5 B. 10 C. 15 D. 20 17. A cell with 20 chromosomes undergoes mitosis, how many chromosomes will each of the 2 new cells have? P 327/ Slide 11 A. 10 B. 20 C. 30 D. 40 18. A cloned plant has a diploid chromosome number of 12. What is the diploid chromosome number of the plant cell that was used to produce the cloned plant? Slide 11. pp 326 A 6 B 12 C 18 D. 24 19. Which statement concerning both mitosis and meiosis is correct? Slide 11 pp 326 (A) meiosis produces 4 haploid cells while mitosis produces 2 diploid cells (B) meiosis produces 4 diploid cells while mitosis produces 2 haploid cells. (C) meiosis maintains the ploidy level, while mitosis reduces it (D) prophase I of mitosis results in the formation of a tetrad but not in prophase I of meiosis 20. If gametes have 8 chromosomes resulting from meiosis how many chromosomes will the body cell have Slide 11/ pp 326 A) 4 B) 8 C) 16 D) 2 E) 1

UNIT 4 Pp 6 21. Which of the following phases of mitosis is represented by the diagram below? Slide 10/11/ pp 326 A. Prophase B. metaphase C. anaphase D. telophase 22. The reduction of the chromosome number during meiosis is most important for —Sl. 10/11/326 A. keeping the amount of DNA in the cell at a minimum level B. preventing the nucleus from becoming larger with each cell division C. maintaining the chromosome number during sexual reproduction D. allowing the growth of the cell without increasing the DNA content 23. Which of the following are mismatched Slide 10 /326 A) haploid-n B) somatic cells-2 n C) zygote-n D) sperm cell-n E) gamete-n 24. Germ-line cells are- A. produce gametes B. are haploid C. usually undergo mitosis D. are special somatic cells Slide 11/ pp 326 25. If a zygote has 4 chromosomes, the somatic cells formed from it have ________ chromosomes. Slide 10/ pp 326 A. 4 B. 8 C. 2 D. 1 E. 16 26. Unlike gametes, body cells are called –A. somatic B) haploid C) semantic D) synergic Slide 10/ pp 326 27. If a somatic human cell were just about to divide, how many chromatids would it have? Slide 10/ 326 A) 92 B) 46 C) 23 D) 0 28. Which of the following represents the phases of mitosis in their proper sequence? Slide 11/ pp 326 A. prophase, metaphase, anaphase, telophase B. interphase, prophase, metaphase, anaphase, telophase C. interphase, prophase, metaphase, telophase D. prophase, anaphase, metaphase, telophase 29. At which cell cycle checkpoint is the cell cycle halted if the cell's DNA is damaged? Slide 5 /PP 277 A) they both involve two parents B) they both require meiosis to complete the reproductive cycle C) they can both occur in multicellular organisms D) they both give rise to genetically distinct offspring 30. Meiosis sex cells, takes place in which of the following organs? Pp 326/Slide 10. (A) Testes (B) Lungs (C) Heart (D) Stomach (E) Skin

UNIT 4 CELL DIVISION 31. If 2 n = 8, for a particular cell, then the chromosome number in egg cell after meiosis would be Pp 326 /Slide 10 (A ) 12 (B) 10 (C) 8 (D) 4 32. Crossing over ______. Pp 324 Slide 19 A) is the exchange of genetic material between non-homologous chromosomes. C) produces a tetrad that contains one or more chiasmata. B) occurs during prophase II D) none of the above 33. What advantage do sexually reproducing organisms have over asexually reproducing organisms? Slide 14 A. genetic variation B. genetic stability C. increased fertilization rate D. increased reproductive rate 34. What is the primary cause of variation in the offspring of sexually reproducing organisms? Slide 14 A. cytoplasmic division B. environmental changes C. Mutation D. recombination of alleles 35. A plant nursery only grew one type of tomato plant. All of their tomato plants died from the same disease. What was most likely true of the tomato plant population? Slide 14/ pp 277 A. They had a lot of resistance to disease. B. They had a few plants that were resistant to the disease. C. They had too much variation in their genes. D. They had little variation in their genes. 36. How are sexual reproduction and asexual reproduction different from each other? Slide 14 /pp 277 A. sexual reproduction requires two parents and asexual reproduction requires only one parent B. asexual reproduction requires two parents and sexual reproduction requires only one parent C. mutation rates are lower in sexual reproduction than in asexual reproduction D. asexual reproduction occurs only in multicellular organisms 37. Which description best identifies characteristics of asexual reproduction? Slide 14 /pp 277 A. one parent, union of gametes, offspring genetically identical to parent B. one parent, no union of gametes, offspring genetically identical to the parent C. two parents, union of gametes, offspring similar to but not genetically identical to parents D. two parents, no union of gametes, offspring genetically identical to the parents 38. Which process is an example of asexual reproduction? Slide 15 /pp 277 A. An amoeba divides in half to form two amoebas. B. bee transfers pollen from one flower to another. C. Female fish deposits eggs on a rock, then a male fish releases sperm on them. D. Earthworms exchange sperm 39. A single-celled eukaryotic amoeba is dividing into 2 cells. Each new cell becomes an individual organism is----Sl 15 A. Budding B) asexual reproduction C) sexual reproduction D) fragmentation E) binary fission 40. Sexual reproduction favors Slide 14 /PP 277 A. Genetic stability B) highly successful species C) stable populations D) beneficial recombination E) genetic diversity

41. In pea plants, green is a recessive trait. A green pea plant would have: pp 310 A. two recessive allele B. two dominant allele C. a dominant + recessive allele 42. The sex chromosomes of normal females are: Pp 393/Slide 21. ( A. ) X and Y Slide 20 (B. ) Y and Y (C. ) X and X (D) none of the above 43. A karyotype is a: pp 401 -402 Slide 26 A) general term for any type of chromosome B) type of abnormal chromosome that is associated with Down's syndrome C) picture of an individual's chromosomes arranged in a standardized way D)A diagram of inheritance of traits 44. Normal humans have _____ pairs of autosomes and ______ pair(s) of sex chromosomes pp 393 Sl. 26 A. 23 and 23 B. 23 and 2 C. 46 and 1 D. 22 and 1 45. In pea plants, tall plants are dominant to short plants. If two heterozygous tall plants are crossed, what percent of the offspring will probably be short? Pp 316/ Slide 20 A. 50% B. 25% C. 0% D. 75% 46. Some flowers show incomplete dominance. If RR = white and R′R′ = red, which phenotypic ratio would be expected in the offspring of two pink flowers? Pp 319. Slide 21 A. 1 red : 2 pink : 1 white B. 0 red : 4 pink : 0 white C. 3 red : 0 pink : 1 white D. 4 red : 0 pink : 0 white 47. In the Punnett square shown in Figure-3, which of the following is true about the offspring resulting from the cross? T=tall and t=short pp 314 Sl. 20 A. About half are expected to be short. B. All are expected to be short. T t C. About three fourths are expected to be tall. D. All are expected to be tall. 48. Which of the following crosses does not follow Mendel’s law of segregation? Pp 314 Sl. 20 A. Two tall pea plants (Tt x Tt) are expected to produce some tall offspring plants. B. Two tall pea plants (Tt x Tt) are expected to produce some short offspring plants. C. A tall pea plant and a short pea plant (Tt x tt) are expected to produce all tall offspring plants. D. A tall pea plant and a short pea plant (TT x tt) are expected to produce all tall offspring plants. T TT Tt tt 49. Most sex-linked, recessive traits–including hemophilia+color blindness appear in males. Sl. 21 This phenomenon is best explained by which statement? A. Males have an X chromosome with dominant genes. B. Most of the genes on the X and Y chromosomes of males are recessive. C. In males, the recessive sex-linked genes appear only on the Y chromosome. D. In males, the Y chromosome lacks the genes needed to mask the recessive genes on the X chromosome. 50. Who is the father of Genetics? A. Darwin B. Mendel. Watson + Crick D. Robert Hooke Sl. 25

UNIT 4 pp 7 3

Unit 4 pp 2.