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. |
Want to see more full solutions like this?
Chapter 13 Solutions
Study Guide for Campbell Biology
- What are Clathrin coated vesicles and what is their function?arrow_forwardHow is a protein destined for the Endoplasmic Reticulum (ER), imported into the ER? Be concise.arrow_forwardFind out about the organisations and the movements aimed at the conservation of our natural resources. Eg Chipko movement and Greenpeace. Make a project report on such an organisation.arrow_forward
- What are biofertilizers and mention the significancearrow_forwardPCBs and River Otters: Otters in Washington State’s Green-Duwamish River have high levels of polychlorinated biphenyls (PCBs) in their livers. PCBs can bind to the estrogen receptors in animals and disrupt the endocrine system of these otters. The PCBs seem to increase the estrogen to androgen ratio, skewing the ratio toward too much estrogen. How would increased estrogen affect the river otter population? Based on your reading of the materials in this unit, what factors can affect fertility in humans? Explain how each of the factors affecting human fertility that you described can disrupt the human endocrine system to affect reproduction.arrow_forwardOther than oil and alcohol, are there other liquids you could compare to water (that are liquid at room temperature)? How is water unique compared to these other liquids? What follow-up experiment would you like to do, and how would you relate it to your life?arrow_forward
- Selection of Traits What adaptations do scavengers have for locating and feeding on prey? What adaptations do predators have for capturing and consuming prey?arrow_forwardCompetition Between Species What natural processes limit populations from growing too large? What are some resources organisms can compete over in their natural habitat?arrow_forwardSpecies Interactions Explain how predators, prey and scavengers interact. Explain whether predators and scavengers are necessary or beneficial for an ecosystem.arrow_forward
- magine that you are conducting research on fruit type and seed dispersal. You submitted a paper to a peer-reviewed journal that addresses the factors that impact fruit type and seed dispersal mechanisms in plants of Central America. The editor of the journal communicates that your paper may be published if you make ‘minor revisions’ to the document. Describe two characteristics that you would expect in seeds that are dispersed by the wind. Contrast this with what you would expect for seeds that are gathered, buried or eaten by animals, and explain why they are different. (Editor’s note: Providing this information in your discussion will help readers to consider the significance of the research).arrow_forwardWhat is the difference between Uniporters, Symporters and Antiporters? Which of these are examples of active transport?arrow_forwardWhat are coupled transporters?arrow_forward
- Biology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage LearningConcepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College
- Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage LearningHuman Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage LearningHuman Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning