...|2.3 Cell Continuity |Objectives | |2.3 Cell continuity + Mitosis |Explain the terms: cell continuity & chromosomes. | | |Define the terms: haploid & diploid number. | | |Describe the cell activities in the state of non-division: Interphase and | | |Division (mitosis). | | |Define the term: mitosis. | | |Define cancer and state causes. | | |State the primary function of mitosis for single-celled vs multi-cell. Organisms.| | |Define the term: meiosis. | ...
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...Leukemia The body is composed of little cells, such as skin cells, muscle cells, heart cells, nerve cells, and bone cells. These cells turn a bit bigger, then divides to shape new cells as the body needs them (1,2). After that, when cells become old or get to be harmed, they die then a new cells take their place (2). On the other hand, in a cancerous cell this systematic breaks down (2). These cancerous cells turn out to be abnormal, old, or harmed. As a result, the process of normal cell division is different from the process of cancer cell division. Leukemia begins in the soft, inward part of the bones (bone marrow), yet regularly moves rapidly into the blood. It can then spread to different parts of the body, for example, the lymph hubs, spleen, liver, and the central nervous system (3)....
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...Mastering Concepts 8.1 1. Explain the roles of mitotic cell division, meiosis, and fertilization in the human life cycle. Mitotic cell division allows for tissue repair/replacement and for an organism’s development from a fertilized egg (zygote) to an adult. Meiosis creates genetically variable gametes that each contain half the genetic material of a nonreproductive cell. The male gamete fertilizes the female gamete during sexual reproduction, forming a zygote with a full set of genetic material. 2. Why are both cell division and apoptosis necessary for the development of an organism? Cell division produces the new cells that make up an organism. Apoptosis (programmed cell death) carves out structures such as fingers and toes; it also protects an organism by eliminating damaged cells that might otherwise become cancerous. 8.2 1. Why does DNA replicate? DNA replicates before a cell divides so that each daughter cell receives a complete set of genetic information. 2. What is semiconservative replication? Semiconservative replication means that only one strand of a DNA molecule is newly formed. The other strand is original DNA from the parent cell. 3. What are the steps of DNA replication? The helicase enzyme unwinds and separates a double-stranded DNA molecule; binding proteins keep the strands separate. The primase enzyme forms a short stretch of complementary RNA on each DNA template. Starting at the end of the RNA primer, DNA polymerase adds...
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...THE CELL CYCLE WORKSHEET Name: Catherine Dauw Date: 3 Novmeber 2015 Per: A A) The diagram below shows six cells in various phases of the cell cycle. Note the cells are not arranged in the order in which the cell cycle occurs. Use the diagram to answer questions 1-11. M Phase 1. Cells A & F show an early and a late stage of the same phase of the cell cycle. What phase is it? C 2. Which cell is in metaphase? A 3. Which cell is in the first phase of M phase (mitosis)? D (interphase), A (prophase), F (prophase), C (metaphase), E (anaphase), and B (telephase) 4. List the diagrams in order from first to last in the cell cycle. 5. In cell A, what structure is labeled X? spindle fibers 6. Are the cells depicted...
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...reproduction is true? A) Cell division only occurs after sexual reproduction. B) Only offspring from asexual reproduction inherit traits from two parents. C) Sexual reproduction typically includes the development of unfertilized eggs. D) Sexual reproduction is more likely to increase genetic variation than is asexual reproduction. E) Only asexual reproduction results from the union of a sperm and an egg. Answer: D 3) Strictly speaking, the phrase "like begets like" refers to A) all forms of reproduction. B) sexual reproduction only. C) asexual reproduction only. D) production of gametes from a premeiotic cell. E) sexual reproduction between different species. Answer: C 4) Asexual reproduction requires ________ individual (s). A) 0 B) 1 C) 2 D) 3 E) 4 Answer B 5) With the exception of identical twins, siblings who have the same two biological parents are likely to look similar, but not identical, to each other because we have A) identical chromosomes, but different genes. B) identical genes but different chromosomes. C) the same combination of traits, but different genes. D) only a 20% chance of sharing the same combination of genes. E) a similar but not identical combination of genes. Answer: E 6) Virchow's principle, stated formally in 1858, was that A) animals must always reproduce. B) photosynthesis is the center of all life. C) animals must develop. D) every cell comes from a cell. E) all life evolves. ...
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...Joe Sawaya Introduction: Mitosis is a process when a cell divides into 2 daughter cells that genetically identical to each other and to the parent cell. All cells come from preexisting cells by mitosis. Cell division involves a karyokinesis (division of the nucleus) and a cytokinesis (division of the cytoplasm). Mitosis produces the same number of chromosomes in each daughter cell as in the original nucleus which are inherited form a generation to another. It also causes a growth in the organism by increasing the number of cells. Not all somatic cells divide; muscle cells, blood cells, cardiac cells, nerve cells don’t divide. Every cell undergoes a series of steps through its life in a cycle called the cell cycle. It’s divided into 4 stages: the G1 (first gap) phase, the S (synthesis) phase, the G2 (second gap) phase and the M (mitosis) phase. -In the G1 phase, the DNA begins to replicate, the cell is in a period of growth and cellular activity. Its duration is about 10 hours. -In the S phase, the DNA is replicated and series of preparation for division occur. -The G2 phase is a second period of growth and cell’s life. It ends when mitosis begins and its duration is about 4 hours. These 3 stages are grouped into one phase which is interphase. -Mitosis is the final stage in the cell cycle. It ends with cytokinesis and its duration is about 1 hour. At its turn, mitosis contains 4 phases: prophase, metaphase, anaphase and telophase which are discussed below. The process...
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...meiotic division (meiosis I), during which maternal and paternal homologous pairs are separated on microtubules. Anaphase 2 - The fourth stage of the second meiotic division (meiosis II), during which either maternal or paternal sister chromatids are separated on microtubules. Chiasma - The region of physical linkage between maternal and paternal homologous pairs during genetic reassortment. Marks the location of crossover between two nonsister chromatids. Diploid number - The total number of chromosomes present in a cell. Gametes - Cells with the haploid number of chromosomes. Gametes are created out of germ cells. The sperm and eggs involved in sexual reproduction are gametes. Genetic Reassortment - A process in which DNA packaged as a chromosome is broken and fragments are exchanged with another independent chromosome. Occurs during prophase 1 of meiosis. Germ cell - Cells that lead to the production of gametes. Produced by meiosis. Haploid number - The number of unique chromosomes or homologous pairs in a cell. Half the diploid number. Homologous pair - Refers to two similar chromosomes in a diploid cell. One chromosome is derived from the father gamete cell and the other from the mother gamete. Meiosis - A type of cellular reproduction that results in the formation of four haploid cells from one diploid cell. Contains two cellular divisions that follow only one round of DNA replication. The type of reproduction that produces germ cells. Metaphase...
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...Questions: (1 pt each response, 7 pts total) 3. What does your data indicate about the rate of cell division in cancerous tissue compared to the rate of cell division in normal tissue? What data did you use to answer this question? Answer: By comparing table 3 (normal cell tissue table) and table 4 (cancerous cell tissue table) I found that cancerous cell tissue has much faster rate of cell division. Specifically, I looked at the mitotic indexes on both tables and found that cancerous cell tissue actively divides at a much faster rate than normal cell tissue. 4. Which type of cancer is the fastest growing? Explain your answer, using your relevant data. Answer: By looking at the mitotic index side of table 4 (cancerous cell tissue table) I found that ovarian cancer has the fastest growth rate. 5. With what you have observed in this lab, if you were to compare tissue sample from normal breast tissue and cancerous breast tissue: a. Would you expect to see a difference in the rate of cell division...
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...2/24/2013 Cell division • The human body is made up of trillions of cells… Mitosis and Meiosis • …But started with one Understanding Cell Division • What instructions are necessary for inheritance? • How are those instructions duplicated for distribution into daughter cells? • By what mechanisms are instructions parceled out to daughter cells? Reproduction • Parental cells produce a new generation of cells or multicelled individuals like themselves • Parents must provide daughter cells with hereditary instructions, encoded in DNA, and enough metabolic machinery to start up their own operation The roles of mitosis Chromosome • A DNA molecule & attached proteins • Duplicated in preparation for mitosis 1 2/24/2013 Chromosomal Organization A chromosomes is DNA associated with proteins. The entire complex is tightly wound and compressed into a discrete, linear structure. The Cell Cycle • • • • • Interphase Usually longest part of the cycle Cell increases in mass Number of cytoplasmic components doubles G1, S, and G2 phases Chromosomes duplicate in S phase of interphase Chromosome Duplication a One chromosome (unduplicated) Duplication allows a whole copy of the genome to reside in each daughter cell one chromatid one chromatid b One chromosome (duplicated) two sister chromatids Each duplicated chromosome will split. One sister chromatid will be in each new daughter cell 2 2/24/2013 Chromosome Number • Sum total...
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...Leukemia - bone marrow stem cells that produce white blood cells Sarcoma - connective tissue, muscle, bone, cartilage Lymphoma - lymph tissue, Hodgkins Adenocarcinoma - glandular epithelia, liver, salivary, breast Cancer Is Uncontrolled Cell Division What Is Cancer? Cell division is the process through which a cell copies itself Cancer begins when the a cell divides although it should not Unregulated cell division leads to a tumor, a mass of cells with no apparent function in the body Benign tumors do not affect surrounding structures Malignant tumors invade surrounding structures and are cancerous Malignant tumors can break away and start new cancers elsewhere through the process of metastasis What Is Cancer? Cancer cells differ from normal cells: Divide when they should not Invade surrounding tissue Move to other locations in the body What Is Cancer? All tissues that undergo cell division, such as ovarian tissue, are susceptible to cancer Cancer Risk Factors Known risk factors are linked to particular cancers… Not all exposures to chemicals and radiation causes cancers Cell Division Overview Cell division produces new cells in order to: Heal wounds Replace damaged cells For growth Also for reproduction Cell Division Overview DNA is organized into structures called chromosomes which can carry hundreds of genes along their length The number of in each cell depends on the organism: humans have 46 Cell Division Overview The “rungs” of...
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...two types of cell divisions in eukaryotes: mitosis, regarding somatic cells and which provides an identical cell to the parent cell during the asexual multiplication cells (it thus preserves genetic information) and meiosis resulting in production of sexual cells or gametes for reproduction. For animals, meiosis is a process that takes place during gametogenesis (spermatogenesis or ovogenesis), that is to say during the development of gametes (sperm in males and eggs in females) in the so-called species diploid. In plants, meiosis produces spores which give by mitosis haploid generation (pollen, leafy foot foam, etc. . ) It gives haploid cells (cells containing n chromosomes) from diploid cells (cell containing 2n chromosomes - in humans, a normal cell contains 2n = 46 chromosomes (ie 23 pairs), while a gamete contains n = 23 chromosomes in two divisions). In haploid species (such as Sordaria macrospora ), meiosis occurs after fertilization to divide the egg cell ( 2n chromosomes). But in addition to the role of division, meiosis has an important role in genetic mixing (miscegenation), thanks to two mechanisms shuffling: the interchromosomal and intrachromosomal shuffling) . Thus, during meiosis, the amount of DNA within the cell varies over time. Each cell will therefore separate genetic heritage (contained in chromosomes) in two to transmit only half of their genes to daughter cells. It takes place in several stages forming a set of two cell divisions, successive...
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...The difference between the cell cycles of a normal and cancerous cell is that the cancerous cell is uncontrolled when it reaches the cell division or anything else goes wrong threwout the cycle(can be very dangerous) and the normal cell is controlled throughout the whole cycle. In the g1 phase, the cell synthesizes mRNA and proteins in preparation for subsequent steps leading to mitosis. When the cell reaches the end of the G1 phase it is controlled at a checkpoint called G1/S, G1/S is when the cell decides whether or not to replicate its DNA. At the checkpoint the cell is checked for DNA. Cells with no damaged DNA (normal cells) continue to S phase, in S phase cells with damaged DNA (cancerous cells) that cannot be repaired die. G2 is when cell is about to divide. the M is...
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...Introduction: Meiosis involves two types of nuclear division that result in four haploid daughter cells. These divisions according to Chapter 15 Meiosis and Sexual Life: Campbell Biology: Tenth Edition are called Meiosis I and Meiosis II, during the first nuclear division the homologous chromosomes separate while during the second division the sister chromatids separate. The stages of Meiosis are: Prophase I, Metaphase I, Anaphase I and Telophase I, this are part of the first division while Prophase II, Metaphase II, Anaphase II and Telophase II are part of the second division of the cell. During this lab, we wanted to know what the stages of meiosis in a plant were and which stages were present in a lily anther. The first generation of lily anther will always produce spores and then this grow and produce gametes, leading the male structure to produce sperm and the female structure to produce eggs. This process leads to the “transmission of traits” from one generation to another. We hypothesized that all the lily anther cells will be in the stages of Telophase I and Telophase II. We also predicted that if the cells were in Telophase I or Telophase II, then the cells were dividing ready to form different ones. Methods:...
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...WHAT IS CELL REPRODUCTION AND WHY IT HAPPENS According to our text book, Essentials of Biology, we begin life as a single cell but over the period of several months, we become a collection of trillions of cells. This process continues as we grow up and as we reach a fully mature adult age, old cells are replaced with new ones. Many cells divide at least once during their short life span and some divide many times before they die. This is known as cell division (parent cells and daughter cells) which are given the names of binary fission, meiosis and mitosis. New red blood cells, skin cells and digestive track cells are also generated. Reproduction is also how organisms are able to reproduce through meiosis which involves the replication of DNA and the splitting of molecules. Mitosis involves the cell division which produces two of the same identical cells from one single cell and happens as a result of a process that cells go through to form to nuclei with each of the nuclei containing the same number of chromosomes. Many eukaryotic organisms use this process for reproduction. Cells go though many cycles but all of the cycles happen in a specific event, some of which I partially mentioned above. The first in the Interphase cycle which is time it takes for a cell to perform its normal functions, depending on where it is in the human body. The next stage is the M state which includes both the division of the nucleus and the division of the cytoplasm—this is where...
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...BY 101 Study Guide Chapter 9 – Cell Division Cell division is an elegant process that enables organisms to grow and reproduce. Through a sequence of steps, the replicated genetic material (chromosomes) in a parent cell is equally distributed to two daughter cells. While there are some subtle differences, mitosis is remarkably similar across organisms. Before a dividing cell enters mitosis, it undergoes a period of growth called interphase. Interphase is the "holding" stage or the stage between two successive cell divisions. In this stage, the cell replicates its genetic material and organelles in preparation for division. The cell cycle, or cell-division cycle, is the series of events that take place in a cell leading to its division and duplication (replication). The cell cycle consists of four distinct phases: G1 phase, S phase (synthesis), G2 phase (collectively known as interphase) and M phase (mitosis). M phase is itself composed of two tightly coupled processes: mitosis, in which the cell's chromosomes are divided between the two daughter cells, and cytokinesis, in which the cell's cytoplasm divides forming distinct cells. Activation of each phase is dependent on the proper progression and completion of the previous one. Cells that have temporarily or reversibly stopped dividing are said to have entered a state of quiescence called G0 phase. Mitosis is composed of several stages: * Prophase * Metaphase * Anaphase * Telophase Prophase ...
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