Cell Cycle Mitosis Meiosis Worksheet Answers

Lesson 1 Cell Division and the Cell Cycle Lesson 1: True or False Name: Daviyunna Reese Class: Biology Date: Nov.18.22 Write true if the statement is true or false if the statement is false. False 1. Cell division is basically the same in prokaryotic and eukaryotic cells. True 2. Cytokinesis is the division of the cytoplasm. True 3. Mitosis is the process in which the nucleus of the cell divides. True 4. DNA replication results in identical chromosomes. True 5. A cell spends most of its life in growth phase 1 of the cell cycle. False 6. The S checkpoint, just before entry into S phase, makes the key decision of whether the cell should divide. True 7. The correct order of phases of the cell cycle is G1 → S → G2 → M. False 8. Interphase consists of mitosis and cytokinesis. False 9. In prokaryotic cells, all organelles, such as the Golgi apparatus and endoplasmic reticulum, divide prior to cell division. False 10. Bacteria divide cells by binary fusion. True 11. A mass of abnormal cells is called a tumor. True 12. Organelles are made during growth phase 2. True 13. In eukaryotic cells, DNA is replicated during the S phase of the cell cycle. True 14. If the cell cycle is not regulated, cancer may develop. False 15. Mitosis occurs in both prokaryotic and eukaryotic cells. Lesson 1: Critical Reading Read these passages from the text and answer the questions that follow. The Cell Cycle Cell division is just one of several stages that a cell goes through during its lifetime. The cell cycle is a repeating series of events, including growth, DNA synthesis, and cell division. The cell cycle in prokaryotes is quite simple: the cell grows, its DNA replicates, and the cell divides. In eukaryotes, the cell cycle is more complicated. Eukaryotic Cell Cycle The diagram in the figure below represents the cell cycle of a eukaryotic cell. As you can see, the eukaryotic cell cycle has several phases. The mitosis phase (M) actually includes both mitosis and cytokinesis. This is when the nucleus and then the cytoplasm divide. The other three phases (G1, S, and G2) are generally grouped together as interphase. During interphase, the cell grows, performs routine life processes, and prepares to divide. These phases are discussed below. Eukaryotic Cell Cycle. This diagram represents the cell cycle in eukaryotes. The G1, S, and G2 phases make up interphase (I). The M phase includes mitosis and cytokinesis. After the M phase, two cells result. Interphase Interphase of the eukaryotic cell cycle can be subdivided into the following three phases, which are represented in the figure above: • Growth Phase 1 (G1): During this phase, the cell grows rapidly, while performing routine metabolic processes. It also makes proteins needed for DNA replication and copies some of its organelles in preparation for cell division. A cell typically spends most of its life in this phase. • Synthesis Phase (S): During this phase, the cell’s DNA is copied in the process of DNA replication. • Growth Phase 2 (G2): During this phase, the cell makes final preparations to divide. For example, it makes additional proteins and organelles. Cancer and the Cell Cycle Cancer is a disease that occurs when the cell cycle is no longer regulated. This may happen because a cell’s DNA becomes damaged. Damage can occur because of exposure to hazards such as radiation or toxic chemicals. Cancerous cells generally divide much faster than normal cells. They may form a mass of abnormal cells called a tumor. The rapidly dividing cells take up nutrients and space that normal cells need. This can damage tissues and organs and eventually lead to death. Questions 1. What is the cell cycle? The cell cycle is a repeating series of events, including growth, DNA synthesis, and cell division 2. What are the phases of the eukaryotic cell cycle? The Mitosis phase, Growth phase 1, Synthesis phase, and Growth phase 2 3. In which phase does a cell spend most of its life? What happens during this phase? A cell spends most of its life in the Growth phase 1. What happens during this phase is that it makes proteins that are needed for DNA replication and copy some of its organelles in preparation for interphase 4. What is cancer? What may cause cancer to occur? Cancer is a disease that occurs when the cell is no longer regulated. The cell’s DNA becomes damaged is what causes cancer to occur. 5. What is the S phase? What happens during this phase? S phase is Synthesis phase. During the S phase the cell’s DNA is copied in the process of DNA replication. Lesson 1: Multiple Choice Circle the letter of the correct choice. (If completing in Microsoft Word, make the correct answer BOLD). 1. Which cells undergo cell division? (a) prokaryotic cells only (b) eukaryotic cells only (c) cancer cells only (d) both prokaryotic and eukaryotic cells 2. Cell division in eukaryotic cells is a complex process because of (a) the multiple chromosomes. (b) the nucleus. (c) the many organelles. (d) all of the above 3. Most routine metabolic processes occur during which phase of the cell cycle? (a) growth phase 1 (b) the S phase (c) growth phase 2 (d) the M phase 4. The correct order of the eukaryotic cell cycle is (a) G1 → G2 → S → M. (b) S → G1 → G2 → M. (c) M → G1 → S → G2. (d) G1 → S → G2 → M. 5. The correct order of prokaryotic cell division is (a) cytokinesis → DNA replication → chromosome segregation. (b) DNA replication → chromosome segregation → cytokinesis. (c) growth → DNA replication → mitosis. (d) DNA replication→ mitosis → cytokinesis. 6. Which cell cycle checkpoint determines whether the DNA has been replicated correctly? (a) the cell growth checkpoint (b) the DNA synthesis checkpoint (c) the mitosis checkpoint (d) the G2 checkpoint 7. What happens during mitosis? (a) The nucleus of the cell divides. (b) The cytoplasm of the cell divides. (c) The cell divides. (d) The DNA replicates. 8. Cell division in prokaryotic cells is called (a) binary fission. (b) binary fusion. (c) mitosis. (d) cytokinesis. Lesson 1: Vocabulary I Match the vocabulary word with the proper definition. Definitions d1. the process in which one cell divides to form two daughter cells f 2. the process in which all of the nuclear DNA is copied c 3. a repeating series of events that describes the life of a cell i 4. phase of the cell cycle that includes the G1, S, and G2 phases a 5. the process by which bacterial cells divide k 6. phase of the cell cycle in which the cell’s DNA is copied b 7. occurs when the cell cycle is no longer regulated g 8. phase of the cell cycle in which the cell grows rapidly and performs many metabolic processes h 9. phase of the cell cycle in which the cell makes final preparations to divide. e 10. division of the cytoplasm, resulting in two daughter cells l 11. an abnormal mass of cells j 12. the process in which the nucleus of the cell divides Terms a. binary fission b. cancer c. cell cycle d. cell division e. cytokinesis f. DNA replication g. growth Phase 1 h. growth phase 2 i. interphase j. mitosis k. synthesis phase l. tumor Lesson 1: Vocabulary II Fill in the blank with the appropriate term. 1. Cancer is a disease that occurs when the cell cycle is no longer regulated. 2. During mitosis the nucleus of the cell divides. 3. interphase consists of the G1, S, and G2 phases of the cell cycle. 4. During the synthesis phase, the cell’s DNA is copied in the process of DNA replication. 5. Cell division in prokaryotes occurs by binary fission. 6. During mitosis, the chromosomes are sorted and separated to ensure that each daughter cell receives a complete set. 7. During cytokinesis, the cytoplasm divides. 8. checkpoints in the cell cycle ensure that the cell is ready to proceed before it moves on to the next phase of the cycle. 9. After cell division, the new cells are referred to as daughter cells. 10. Chromosome segregation refers to the two chromosomes separating and moving to opposite ends of the cell. 11. In eukaryotes, the first step in cell division is mitosis, and the second step is cytokinesis. 12. The cell cycle is controlled by regulatory proteins at three key checkpoints. Lesson 1: Critical Writing Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences. Describe the eukaryotic cell cycle, listing and discussing the main events of each phase. The eukaryotic cell cycle is split into two parts the interphase and mitosis. In the interphase its split into three phases which are the Growth Phase 1, Synthesis phase, and the Growth phase 2. During the Growth phase 1 the cells make proteins needed for DNA replication and copies some of its organelles in preparation for cell division. During the Synthesis phase the cell’s DNA is copied in the process of DNA replication During the Growth phase 2 the cell makes final preparations to divide. The mitosis phase includes both mitosis and cytokinesis. This occurs when the nucleus and the cytoplasm divide. Lesson 2 Chromosomes and Mitosis Lesson 2: True or False Write true if the statement is true or false if the statement is false. True 1. A chromatid is made of two identical chromosomes. True 2. There may be thousands of genes on a single chromosome. True 3. Prophase is the first phase of mitosis. True 4. Female human cells have 23 pairs of homologous chromosomes. False 5. Mitosis occurs in the following order: prophase - metaphase - telophase - anaphase. True 6. The process in which the cell divides is called mitosis. False 7. During mitosis, DNA exists as chromatin. True 8. A gene contains the instructions to make a protein. False 9. Chromosomes form during metaphase. False 10. Mitosis is the phase of the eukaryotic cell cycle that occurs between DNA replication and the second growth phase. True 11. Sister chromatids are identical. True 12. Chromatids separate during anaphase. True 13. Chromosomes are coiled structures made of DNA and proteins. False 14. Human cells have 64 chromosomes. True 15. Cytokinesis is the final stage of cell division. Lesson 2: Critical Reading Read these passages from the text and answer the questions that follow. Chromosomes Chromosomes are coiled structures made of DNA and proteins. Chromosomes are the form of the genetic material of a cell during cell division. During other phases of the cell cycle, DNA is not coiled into chromosomes. Instead, it exists as a grainy material called chromatin. Chromatids and the Centromere DNA condenses and coils into the familiar X-shaped form of a chromosome only after it has replicated, as seen in the figure below. Because DNA has already replicated, each chromosome actually consists of two identical copies. The two copies are called sister chromatids. They are attached to one another at a region called the centromere. Chromosomes and Genes The DNA of a chromosome is encoded with genetic instructions for making proteins. These instructions are organized into units called genes. Most genes contain the instructions for a single protein. There may be hundreds or even thousands of genes on a single chromosome. Human Chromosomes Human cells normally have two sets of chromosomes, one set inherited from each parent. There are 23 chromosomes in each set, for a total of 46 chromosomes per cell. Each chromosome in one set is matched by a chromosome of the same type in the other set, so there are actually 23 pairs of chromosomes per cell. Each pair consists of chromosomes of the same size and shape that also contain the same genes. The chromosomes in a pair are known as homologous chromosomes. Questions 1. What is a chromosome? What is it made out of? Chromosome are coiled structures made of DNA and proteins. It is made out of the form of genetic material of a cell during cell division. 2. What are homologous chromosomes? How many homologous pairs are in a human cell? Chromosomes in a pair are homologous chromosomes. There are 23 homologous pairs in a human cell. 3. What is the main difference between chromatin and chromosomes? Chromatin is a grainy material that condenses into chromosomes. 4. Why do chromosomes look like an “X”? DNA condenses and coils into the X-shape form of a chromosome because there are two copies that attach at the centromere. 5. What is a gene? A gene contains the instructions for single proteins. Lesson 2: Multiple Choice Circle the letter of the correct choice. (If completing in Microsoft Word, make the correct answer BOLD). 1. Why is it necessary for the DNA to replicate prior to cell division? (a) so that each daughter cell will have 23 chromosomes (b) so that each daughter cell will have a complete copy of the genetic material (c) so that each daughter cell will have 46 homologous chromosomes (d) so that each daughter cell will have 2 sister chromatids 2. Why do chromosomes have an X-shape? (a) because they are made of two sister chromatins (b) because they are made of two sister centromeres (c) because they are made of two sister chromosomes (d) because they are made of two sister chromatids 3. Chromosomes form during what part of the cell cycle? (a) prophase of mitosis (b) the end of the G2 phase (c) right after S phase and DNA replication (d) during cytokinesis 4. The correct order of phases during mitosis is (a) telophase→prophase→metaphase→anaphase (b) prophase→anaphase→metaphase→telophase (c) prophase→metaphase→telophase→anaphase (d) prophase→metaphase→anaphase→telophase 5. How many chromosomes are in a normal human cell? (a) 23 (b) 32 (c) 46 (d) 64 6. When do the sister chromatids line up at the equator of the cell? (a) metaphase (b) anaphase (c) prophase (d) telophase 7. Which of the following statements concerning cytokinesis is correct? (1) cytokinesis occurs in both prokaryotes and eukaryotes, (2) cytokinesis is when the cytoplasm splits in two, (3) in plant cells, cytokinesis involves the formation of a cell plate. (a) 1 only (b) 2 only (c) 1 and 2 (d) 1, 2, and 3 8. During which phase of mitosis do the sister chromatids separate? (a) prophase (b) telophase (c) anaphase (d) metaphase Lesson 2: Vocabulary I Match the vocabulary word with the proper definition. Definitions j 1. division of the nucleus b 2. region of the chromosome where sister chromatids are attached f 3. division of the cytoplasm i 4. phase of mitosis in which spindle fibers attach to the centromere of each pair of sister chromatids e 5. coiled structures made of DNA and proteins a 6. phase of mitosis in which sister chromatids separate and the centromeres divide g 7. a segment of DNA with the genetic instructions to make a protein c 8. two copies of replicated DNA that make a chromosome k 9. the first and longest phase of mitosis d 10. uncoiled DNA h 11. a pair of the same chromosome l 12. phase of mitosis in which the chromosomes begin to uncoil and form chromatin Terms a. anaphase b. centromere c. chromatid d. chromatin e. chromosome f. cytokinesis g. gene h. homologous chromosomes i. metaphase j. mitosis k. prophase l. telophase Lesson 2: Vocabulary II Fill in the blank with the appropriate term. 1. Chromosomes are coiled structures made of DNA and proteins. 2. Mitosis is the division of the nucleus. 3. During Metaphase sister chromatids line up at the equator, or center, of the cell. 4. Cytokinesis is the division of the cytoplasm. 5. There may be hundreds or even thousands of genes on a single Chromosome 6. A Gene contains genetic the instructions for making proteins. 7. During anaphase, sister Chromatids separate and the centromeres divide. 8. The four phases of mitosis, in order, are prophase, metaphase, anaphase, and telophase. 9. Human cells normally have 46 chromosomes. 10. A new nuclear membrane forms during telophase 11. The Spindle fibers ensure that sister chromatids will separate when the cell divides. 12. When a chromosome first forms, it actually consists of two sister Chromatids. Lesson 2: Critical Writing Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences. Describe the structure of a chromosome, using proper vocabulary. Discuss when and why a chromosome forms. A chromosome is an "X" shaped structure that consists of thousands of genes, four chromatids which is the 2 sister chromatids, and a centromere. Chromosomes are formed during prophase of cell division when chromatin condenses. Chromosome forms so that each daughter cell gets the same amount of identical genetic material Lesson 3 Reproduction and Meiosis Lesson 3: True or False Write true if the statement is true or false if the statement is false. False 1. The basic types of reproduction are asexual reproduction, binary reproduction and sexual reproduction. True 2. Sexual reproduction always involves two parents. False 3. Asexual reproduction always involves two parents. True 4. Meiosis starts with one cell and ends with four. True 5. “Crossing-over” can occur in meiosis I but not meiosis II. False 6. Prokaryotes go through meiosis I and eukaryotes go through meiosis II. True 7. A zygote is the first cell of a new organism. False 8. Meiosis I and mitosis are very similar. True 9. In humans, a gamete will have 23 chromosomes. True 10. In binary fission, parent and o spring are identical. True 11. In sexual reproduction, parents and o spring are never identical. False 12. Gametes are diploid, a zygote is haploid. False 13. Egg and sperm are diploid gametes. True 14. Meiosis is involved in the production of gametes. True 15. Starfish can reproduce by fragmentation - that is, a whole new fish can grow from just a single arm. Lesson 5.3: Critical Reading Read these passages from the text and answer the questions that follow. Meiosis The process that produces haploid gametes is meiosis. Meiosis is a type of cell division in which the number of chromosomes is reduced by half. It occurs only in certain special cells of the organisms. During meiosis, homologous chromosomes separate, and the haploid cells that form have only one chromosome from each pair. Two cell divisions occur during meiosis, and a total of four haploid cells are produced. The two cell divisions are called meiosis I and meiosis II. Phases of Meiosis Meiosis I begins after DNA replicates during interphase. In both meiosis I and meiosis II, cells go through the same four phases as mitosis. However, there are important di erences between meiosis I and mitosis. Meiosis I 1. Prophase I: The nuclear envelope begins to break down, and the chromosomes condense. Centrioles start moving to opposite poles of the cell, and a spindle begins to form. Importantly, homologous chromosomes pair up, which is unique to prophase I. In prophase of mitosis and meiosis II, homologous chromosomes do not form pairs in this way. 2. Metaphase I: Spindle fibers attach to the paired homologous chromosomes. The paired chromosomes line up along the equator of the cell. This occurs only in metaphase I. In metaphase of mitosis and meiosis II, it is sister chromatids that line up along the equator of the cell. 3. Anaphase I: Spindle fibers shorten, and the chromosomes of each homologous pair start to separate from each other. One chromosome of each pair moves toward one pole of the cell, and the other chromosome moves toward the opposite pole. 4. Telophase I and Cytokinesis: The spindle breaks down, and new nuclear membranes form. The cytoplasm of the cell divides, and two haploid daughter cells result. The daughter cells each have a random assortment of chromosomes, with one from each homologous pair. Both daughter cells go on to meiosis II. Meiosis II 1. Prophase II: The nuclear envelope breaks down and the spindle begins to form in each haploid daughter cell from meiosis I. The centrioles also start to separate. 2. Metaphase II: Spindle fibers line up the sister chromatids of each chromosome along the equator of the cell. 3. Anaphase II: Sister chromatids separate and move to opposite poles. 4. Telophase II and Cytokinesis: The spindle breaks down, and new nuclear membranes form. The cytoplasm of each cell divides, and four haploid cells result. Each cell has a unique combination of chromosomes. Questions 1. Define meiosis. Meiosis is a type of cell division in which the number of chromosomes is reduced by half. 2. Is the DNA replicated after meiosis I? Why or why not? No, because DNA is replicated in Interphase first and no interphase stage exists after Meiosis 1. 3. Describe the main difference between metaphase I and metaphase II. In Metaphase 1, it is paired homologous chromosomes line up along the equator of the cell. In Metaphase 2, it is sister chromatids that line up along the equator of the cell. 4. State the phase where each of the following processes occurs: (a) sister chromatids separate, (b) homologous chromosomes form pairs, (c) two haploid cells form. a - Anaphase 2 b - Prophase 1 c -Telophase 2 5. What is final product of meiosis? The final product of meiosis is that it has four haploid cells result meaning each cell is with a unique combination of chromosomes and half of the chromosomes came from the original cell. Lesson 5.3: Multiple Choice Circle the letter of the correct choice. (If completing in Microsoft Word, make the correct answer BOLD). 1. After meiosis there are (a) two haploid cells. (b) two haploid gametes. (c) four haploid cells. (d) four haploid gametes. 2. Which of the following is a form of asexual reproduction? (a) fragmentation (b) meiosis (c) binary fusion (d) bubbling 3. Which of the following is true about a zygote? (1) A zygote is the first cell of a new organism. (2) A human zygote has 23 pairs of chromosomes. (3) A zygote is produced through fertilization. (a) 1 only (b) 1 and 3 (c) 2 and 3 (d) 1, 2, and 3 4. Di erences between meiosis I and meiosis II include: (a) how the chromosomes line up at the equator of the cell during meiosis I or meiosis II. (b) the pairing of chromosomes in meiosis I but not meiosis II. (c) the amount of DNA in a cell at the end of meiosis I or meiosis II. (d) all of the above 5. Because of when the chromosomes pair up during meiosis, crossing-over must occur during (a) prophase II. (b) metaphase II. (c) prophase I. (d) anaphase I. 6. Homologous chromosomes separate during (a) metaphase I. (b) anaphase I. (c) anaphase II. (d) telophase II. 7. A life cycle in which organisms switch back and forth between diploid and haploid stages (a) is a haploid life cycle. (b) is a diploid life cycle. (c) is an alternation of generations life cycle. (d) does not exist. 8. The random distribution of homologous chromosomes during cell division is known as (a) meiosis. (b) independent assortment. (c) genetic variation. (d) crossing-over. Lesson 3: Vocabulary I Match the vocabulary word with the proper definition. Definitions e 1. the process in which two gametes unite b 2. the swapping of genetic material during meiosis j 3. a type of cell division in which the number of chromosomes is reduced by half i 4. series of life stages and events of a sexually reproducing organism a 5. involves a single parent k 6. involves two parents h 7. having half the number of chromosomes c 8. having twice the number of chromosomes l 9. a diploid cell d 10. a haploid cell g 11. the development of haploid cells into gametes f 12. reproductive cells that unite to form an o spring Terms a. asexual reproduction b. crossing-over c. diploid d. egg e. fertilization f. gametes g. gametogenesis h. haploid i. life cycle j. meiosis k. sexual reproduction l. zygote Lesson 3: Vocabulary II Fill in the blank with the appropriate term. 1. When cells divide during meiosis, homologous chromosomes are randomly distributed to daughter cells, and different chromosomes segregate Independently of each other. 2. Crossing-over is the exchange of Genetic material between homologous chromosomes. 3. A human egg cell has 23 chromosomes. 4. Binary fission, fragmentation, and Budding are types of asexual reproduction. 5. Meiosis is a type of cell division in which the number of chromosomes is reduced by half. 6. A human zygote has 46 chromosomes. 7. The Asexual life cycle is the simplest life cycle. 8. Meiosis begins with one cell, and ends with Four cells. 9. Male gametes are called sperm and female gametes are a(n) egg cell. 10. During Prophase 1 spindle fibers attach to the paired homologous chromosomes. 11. Organisms that have a life cycle with Alternation generations switch back and forth between diploid and haploid stages. 12. Sexual reproduction involves two parents. Lesson 3: Critical Writing Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences. List three significant differences between meiosis I and meiosis II. In meiosis I, homologous chromosomes separate, while in meiosis II, sister chromatids separate. In Meiosis II produces 4 haploid daughter cells, whereas Meiosis I produce 2 diploid daughter cells. Genetic recombination same as crossing over only occurs in meiosis I