Chapter 11 - Concept Mapping Using the terms and phrases provided below, complete the concept map showing the process of meiosis. chromatids crossing-over haploid sperm and ovum homologous chromosomes meiosis II Holt Biology 18 Meiosis and Sexual Reproduction
Chapter 11 - Vocabulary Review In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. 1. An organism s reproductive cells, such as sperm or egg cells, are called a. genes. c. gametes. b. chromosomes. d. zygotes. 2. Chromosomes that are similar in size, shape, and genetic content are called which of the following? a. homologous chromosomes c. diploid b. haploid d. ovum 3. When a cell contains two sets of chromosomes, it is said to be a. haploid. c. diploid. b. binary. d. budding. 4. When a cell contains one set of chromosomes, it is said to be a. haploid. c. diploid. b. crossing-over. d. homologous. 5. A type of cell division that halves the number of chromosomes is known as a. anaphase. c. mitosis. b. meiosis. d. gametophyte. 6. What process occurs during prophase I of meiosis? a. cytokinesis c. crossing-over b. random fertilization d. chromosome 7. The union of the gametes during fertilization leads to the production of a(n) a. alternation of generations. c. organism. b. zygote. d. chromosome. 8. The random distribution of homologous chromosomes in the formation of the gametes is a. independent assortment. c. crossing-over. b. zygote. d. chromosome. Holt Biology 19 Meiosis and Sexual Reproduction
Vocabulary Review continued 9. What gamete is produced in quantities of four cells during meiosis? a. asexual c. sporophyte b. ovum d. sperm 10. What gamete is produced as one large cell and three smaller cells during meiosis? a. asexual c. sporophyte b. ova d. sperm 11. Diploid is an example of a a. life cycle. c. haploid cycle. b. cell cycle. d. sperm cell. Holt Biology 20 Meiosis and Sexual Reproduction
11.1 - Directed Reading Section: Reproduction In the space provided, explain how the terms in each pair differ in meaning. 1. asexual reproduction, sexual reproduction 2. binary fission, fragmentation 3. budding, parthenogenesis Read each question, and write your answer in the space provided. 4. What are the advantages and disadvantages of asexual reproduction? 5. What are the advantages of sexual reproduction? Holt Biology 21 Meiosis and Sexual Reproduction
Directed Reading continued Complete each statement by writing the correct term in the space provided. 6. Chromosomes that are similar in size, shape, and genetic content are called. 7. A cell, such as a somatic cell, that contains two sets of chromosomes is said to be. 8. Biologists use the symbol to represent one set of chromosomes. 9. Human somatic cells have chromosomes. Read each question, and write your answer in the space provided. 10. What is the difference between an autosome and a sex chromosome? 11. What are the sex chromosomes in human females and males? What is one major difference between them? Holt Biology 22 Meiosis and Sexual Reproduction
11.2 - Directed Reading Section: Meiosis Read each question, and write your answer in the space provided. 1. What is meiosis? 2. Explain the difference between meiosis I and meiosis II. 3. List the stages of meiosis in the order that they occur. 4. What is crossing-over? 5. What is independent assortment? During which phase(s) of meiosis does independent assortment occur and what is the significance of this process? Holt Biology 23 Meiosis and Sexual Reproduction
Directed Reading continued In the space provided, write the name of the stage of meiosis that is being described. 6. The centromeres divide, and the chromatids move to opposite poles of the cell. 7. The homologous chromosomes separate. The chromosomes of each pair are pulled to opposite poles of the cell by the spindle fibers. The chromatids do not separate at their centromeres. 8. The chromosomes condense, and the nuclear envelope breaks down. Homologous chromosomes pair all along their length and then crossing-over occurs. 9. After one division of the nucleus, a new spindle forms around each group of chromosomes. 10. Individual chromosomes line up along the equator, attached at their centromeres to spindle fibers. 11. A nuclear envelope forms around each set of chromosomes. Two cells undergo cytokinesis, forming haploid offspring cells. 12. Individual chromosomes gather at each of the two poles. In most organisms, the cytoplasm divides, forming two new cells. 13. The pairs of homologous chromosomes are moved by the spindle to the equator of the cell. The homologous chromosomes, each made up of two chromatids, remain together. Holt Biology 24 Meiosis and Sexual Reproduction
11.3 - Directed Reading Section: Multicellular Life Cycles In the space provided, explain how the terms in each pair differ in meaning. 1. diploid life cycle, haploid life cycle 2. sperm, ovum 3. sporophyte, gametophyte Read each question, and write your answer in the space provided. 4. What are spermatogenesis and oogenesis? 5. List the three types of life cycles. Give an example of an organism that undergoes each type of life cycle. Holt Biology 25 Meiosis and Sexual Reproduction
Directed Reading continued 6. How can you tell which type of sexual life cycle an organism undergoes? 7. List the main steps in the diploid life cycle. Begin with meiosis. 8. Why does meiosis produce four sperm cells but only one ovum? Holt Biology 26 Meiosis and Sexual Reproduction