Concept explainers
- a. How many chromosomes are there in the somatic cells of an animal in which 2n = 14? __________How many chromosomes are in its gametes? _________
- b. If n = 14, how many chromosomes are there in diploid somatic cells? _______ How many sets of homologous chromosomes are in the gametes?
- c. If 2n = 28, how many chromatids are there in a cell after chromosome duplication has occurred prior to cell division? ___________ What is the difference between sister chromatids and nonsister chromatids?
a.
To determine: The number of chromosomes present in a somatic cell of an animal in which 2n=14.
Introduction: Chromosomes are long thread like structures present in all cells of the body. These chromosomes contain coded genetic materials in the form of genes and that are transmitted to the succeeding generations by the process of cell division. A diploid cell contains two set of chromosomes, whereas a single set of chromosome is present in haploid cells.
Answer to Problem 1IQ
The number of chromosomes present in the given somatic animal cell is 14.
Explanation of Solution
Somatic cells include all the body cells except the gametes (sperms and ova). Under normal conditions, all the somatic cells exist in a diploid form. It is given that the animals have (2n=14) and (2n) represents the diploid condition of the cell. It is given that the cell is somatic and hence, it is also diploid. Thus, the number of chromosomes present in the given somatic animal cell is 14.
To determine: The number of chromosomes present in the gamete cells of an animal is 2n=14.
Answer to Problem 1IQ
The number of chromosomes present in the cell’s gamete is 7.
Explanation of Solution
Gametes are the reproductive cells and include the sperms and ova. Under normal conditions, all the gametes exist in a haploid condition. It is given that 2n=14 where (2n) indicates diploid condition of the cell. Therefore, the gametes that are haploid have 7 chromosomes in its cell.
b.
To determine: The number of chromosomes present in a diploid somatic cell is n=14.
Introduction: Somatic cells include all the body cells except the gametes. Gametes include the reproductive cells, which are the sperms and ova.
Answer to Problem 1IQ
The number of chromosomes present in a diploid somatic cell, when n=14 is 28.
Explanation of Solution
It is given that n=14 and (n) indicates the haploid condition and when the cells are diploid, the number of chromosomes is 28 (since n=14, 2n=28). Therefore, the diploid somatic cell has 28 chromosomes.
To determine: The number of set of the homologous chromosomes present in the gametes.
Answer to Problem 1IQ
The set of homologous chromosomes present in the gamete is 1.
Explanation of Solution
Homologous chromosomes are the pair of chromosomes containing one maternal and one paternal chromosome. Homologous chromosomes are paired chromosomes that are identical in length, centromere location, and the gene loci but the sequence of the gene varies. The gametes are haploid and hence, they possess only a single set of chromosomes that they contribute it during the fertilization. Therefore, the set of homologous chromosomes present in the gamete is 1.
c.
To determine: The number of chromatids present after the occurrence of duplication of the chromosome prior to the cell division in a cell containing 2n=28.
Introduction: Chromosomes are long thread like structures present in the cell. Each chromosome constitutes two chromosomal arms that are linked together by the centromere. The coded information in the form of genes is arranged in the chromatids.
Answer to Problem 1IQ
The number of chromatids present in the cell after the duplication of chromosome had occurred prior to cell division, when 2n=28 is 56.
Explanation of Solution
If the chromosomes undergo duplication before the onset of cell division, the number of chromosomes in the cell doubles. Since each chromosome has two chromatids, the number of chromatids when 28 chromosomes are present in the cell 56.
To differentiate: Sister chromatids from non-sister chromatids.
Explanation of Solution
Criteria | Sister chromatids | Non-sister chromatids |
Formation | Sister chromatids are formed when the chromosome undergoes duplication during the S phase of interphase. | Non-sister chromatids occur on different chromosomes of the homologous chromosomes. |
Centromere | They are joined by the centromere at the center and all along their length by cohesive proteins. | Since they are present in different chromosomes, they are not linked by the centromere. |
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Chapter 13 Solutions
Study Guide for Campbell Biology
- a. What phase of meiosis is this cell undergoing? b. Identify the 3 things that are incorrect in terms of this cells structure and organization? c. Would this cell produce viable gametes? Why or why not.arrow_forwarda. What phase of Meiosis II is the cell in? How do you know? b. Assuming all of the chromosomes present during Meiosis II are shown in the figure above, how many chromosomes (counting homologous pairs as two chromosomes) does a gamete from this organism have? c. Draw the same cell during the same phase of Meiosis I. Label the elements.arrow_forwardIf a diploid organism has 14 chromosomes (2n=14) a. How many chromosomes will its gametes have? b. After meiosis I during gamete formation, how many chromosomes are in each daughter cell? c. After meiosis I during gamete formation, how many chromatids are in each daughter cell?arrow_forward
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- Which of the statements is FALSE? Somatic cells are diploid in diploid organisms. Gametes are produced from meiosis by germline cells. Somatic cells are capable of both mitosis and meiosis. Somatic cells and gametes from the same organism have different chromosomal complements.arrow_forwardimagine a giraffe whose diploid is 30. A)Under what circumstances would the giraffe go through a process of meiosis? . b) what will be the final result of this meiosis for the giraffe (# of cells + # of chromosomes/cells)arrow_forward5.)Gametogenesis, or the formation of gametes, occurs when diploid germ cells undergo meiosis. In fruit flies (Drosophila melanogaster), diploid germ cells contain eight chromosomes. Which of the following correctly describes the number of chromosomes in the daughter cells produced during gametogenesis in fruit flies? The daughter cells each contain four chromosomes after meiosis I and four chromosomes after meiosis II. The daughter cells each contain eight chromosomes after meiosis I and eight chromosomes after meiosis II. The daughter cells each contain eight chromosomes after meiosis I and four chromosomes after meiosis II. The daughter cells each contain four chromosomes after meiosis I and two chromosomes after meiosis II.arrow_forward
- A. In the beginning of meiosis II, each chromosome is duplicated and attached. These chromosomes are called? _______ B. In meiosis, the process of homologous chromosomes lining up together side-by-side is called ___________arrow_forwardHumans have 46 chromosomes in each somatic cell.a. How many chromosomes does a child receive fromits father?b. How many autosomes and how many sex chromosomes are present in each somatic cell?c. How many chromosomes are present in a humanovum?d. How many sex chromosomes are present in ahuman ovum?arrow_forwardIf a muscle cell of a typical organism has 32 chromosomes, how many chromosomes will be in a gamete of that same organism? a.8 b. 16 c. 32 d. 64arrow_forward
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