Module+6+Review


 * For this Module Exam, please use the cognitive objectives for your review guide. **

** COGNITIVE OBJECTIVES: ** Upon completion of this module the student will be able to:

__Chapter 9__: 1. Distinguish between somatic cells and germ cells. // Somatic cells: ﻿most of the cells in the body.These are the cells mitosis takes place in. A cell that does not participate in the production of gametes. (a cell // // who's genes will not/cannot be passed to the future generations) // // Germ cells: ﻿are immature reproduction cells. They are the cells that are used in Meiosis to produce sperm and egg cells. A n animal cell that can undergo // // meiosis an give rise to gametes // 2. Define the terms //chromatin, chromosome, sister chromatids// and //centromere.// Chromatin: All of the DNA molecules and associated proteins in a nucleus Chromosome: A complete molecule of DNA and it's attached proteins: carries part of all of an organism's genes Linear in eukaryotic cells: circular in prokaryotes. Sister Chromatids: Two attached members of a duplicated eukaryotic chromosome. Centromere: Constricted region in a eukaryotic chromosome where sister chromatids are attached

3. Describe the cell cycle. Name the stages and describe the key events that occur in each stage. // What happens in interphase? // // ﻿A cell increases it's mass, roughly doubles the number of its cytoplasmic components and replicates its DNA.( all this happends in three phases G1,S,G2) // // G1: is when the cell is actively carrying out the normal functions of the cell. If the cell is about to divide then the cells grows in size during this phase by // // creating addition cell membrane, creates additional organelles and increases protein synthesis. // // S: The second phase is S which stands for synthesis. In this phase the DNA is replicated. // // G2: The final phase is where the cell continues forming proteins andorganelles and also double checks to make sure the cells is ready to divide. // // When is the DNA replicated? // // ﻿ ﻿﻿During the time of Synthesis. The DNA is re﻿plicated // // When does mitosis take place? // // ﻿ ﻿Mitosis takes place after Interphase or more specifically after the DNA has been replicated and addition cell parts has been formed. // // How much of the cell cycle is devoted to mitosis? // // ﻿In the cell cycle mitosis devoted a lot of time because it is divided into 4 distinct stages although some times it is difficult to tell when the cell has ﻿transitioned from one to the next. Roughly a fifth of the cell cycle is devoted to mitosis with the majority devoted to interphase. //

4. Explain briefly the significance of mitosis in the life of a cell. List its four main stages and describe in detail the key events and structures involved in each stage. // Use this space to draw out the phases of mitosis and DESCRIBE in words what is going on, using as many vocabulary words as possible. Try to avoid using "plain English” and try and stick to the biological vocabulary you have learned as much as possible. //



Mitosis is extremely important in the life of a cell since it is how a somatic cell reproduces. Mitosis is the basis for increasing body size during developmentand for replacing damaged or dead cells. The four main stages of mitosis are prophase, metephase, anaphase and telephase. PROPHASE: During this phase the chromatin condenses or organizes itself into multliple levels of coiling. The centrosome is duplicated and microtubules from a bipolar spindle by bulling one centrosome to the opposite side of the nucleus. Microtubules attach to the sister chromatids at their centromere to the opposite spindle poles. Lastly the nuclear envelope breaks up, a way to help remember this phase is to know this is where the chromosomes become more pronounced (clearly visible) when viewed under a microscope. METAPHASE: Some of the spindle microtubules pull some of the chromosomes toward one side of the cell while others pull some of the chromosomes toward the other side of the cell until they all line up in the midle of the cell. The remaining microtubules push against each other forcing the two centrioles father away from each other, stretching the cell, away to help remember this phase is to know this is where the chromosomes meet in the middle of the cell. ANAPHASE: During this phase microtubules separate sister chromatids by pulling them to opposite spindle poles. TELOPHASE: During this last phase of mitosis the chromosomes reach the spindle poles. A new nuclear envelope forms around each cluster of chromosomes that were pulled to opposite spindle poles. Lastly the chromosomes decondense. 5. Briefly compare the process of cytokinesis (cytoplasmic division) in plant and animal cells. In plant cells, a cell plate forms in the middle of the cell to create two separate cells. In animals cells, the cytoskeleton fibers pull like a draw string inthe middle of the cell forming what is called a cleavage furrow. __Chapter 10__: 1. Distinguish between //asexual// and //sexual// reproduction. Explain the major biological advantages of sexual reproduction. // asexual //

// sexual //

2. Distinguish between the terms //gene// and //allele.//

3. Describe homologous chromosomes. Where do they come from?

4. State the //diploid number// and //haploid number// for humans. n= 2n= //5.// Describe the key events and stages of Meiosis I and Meiosis II. //Please use your biological vocabulary!//

6. Explain what is meant by “crossing over” and when does it occur during the process of Meiosis. Crossing over is when four strands or tetrads are in such close proximity that some of the genetic information swaps places. It occurs during prophase in meiosis 7. Explain how random fertilization, independent assortment, and crossing over contribute to genetic diversity. Random fertilization is when egg and sperm cells get together. Independent assortment how the tetrads line up during anaphase. Crossing over when homologous chromosomes are so close together they some times exchange genetic information. 8. Compare and contrast the overall process of mitosis and meiosis in terms of the type of cells each occurs in, the number of chromosomes present at the beginning and end of each process, the number of daughter cells produced, and are the daughters identical to each other or not.

Both mitosis and meiosis go through interphase for growth, DNA replication, and prep for cell division and it is also the cell stage that is the longest. Mitosis divides the nucleus but not the cytoplasm and produces two genetically identical daughter cells. Both itosis and meiosis go through interphase, prophase, metaphase, anaphase, telophase, and cytoplasmic division, aka cytokinesis. However, meiosis goes trough the stages twice, begining at prophase. Meiosis involves sexual reproduction from gametes (egg and sperm), the cell is diploid, and produces wide varieties of traits due to crossover. This is where two identical sister strands can swap alleles at the gene's locus. At the ed, four non-identical daughter cells are produced with a haploid number.

__Chapter 11__: 1. Briefly discuss the significance of Mendel’s work to the field of genetics. 2. Define the term //gene.//

3. Define and distinguish between these groups of terms: //“true-breeding” organisms// and //hybrids; P, F1,// and //F2 generations; genotype// and //phenotype; dominant// and //recessive; heterozygous// and //homozygous.// // What is a true breeding organism? //

// P generation: // // F1 // // F2 // // genotype // // phenotype // // dominant genotype: (let’s say for pea plants PP, Pp) // // recessive genotype: (let’s say for pea plants pp) // // heterozygous: // // homozygous: //

4. Predict the phenotypic and genotypic outcome of a simple monohybrid cross. // Do all the combinations you can think of with a monohybrid cross to the F2 generation to make sure you see all the patterns. //

5. Describe the process of running a “//testcross//” to determine an unknown genotype.

5. Explain Mendel’s theories of “//segregation//” and “//independent assortment//”. // I discussed this on Elluminate, watch the recording to hear about it in detail. //

6. Explain the concepts of //incomplete dominance// and //codominance// as they relate to gene expression. //Cite the examples from your text of each of these phenomena.// // Incomplete dominance: //

// Codominance: //

//__ Also, epistasis: __//

//__ Pleiotropy: __//

__Chapter 12__: <span style="font-family: Times New Roman; margin: 6pt 0in 0pt 0.25in; tab-stops: .25in; tabstops: .25in; text-indent: -0.25in;">1. Distinguish between //autosomes// and //sex chromosomes//. State the sex chromosome difference for human males and females.

<span style="font-family: Times New Roman; margin: 6pt 0in 0pt 0.25in; tab-stops: .25in; tabstops: .25in; text-indent: -0.25in;">2. Describe the process of karyotyping. //Don’t forget to do the lab on this and hand it in on Tuesday.// <span style="font-family: Times New Roman; margin: 6pt 0in 0pt 0.25in; tab-stops: .25in; tabstops: .25in; text-indent: -0.25in;">3. Describe the changes in chromosome structure that result due to duplication, inversion, translocation, deletion, and non-disjunction “errors” that occur in meiosis.