This chapter explores mutation and variation under the context of inheritance. It
highlights how genetics offers a vast trove of information about the history of life on
Earth and the evolutionary factors acting on living species. The replication of DNA is an
exquisitely precise affair, but errors can still be made which make mutations the ultimate
source of genetic variation in all organisms. Generally, mutations come in various forms and
these differ in how much of a genome they affect. Some species have mechanisms that
contribute to inheritance and play a role in evolution regardless of genetics.
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Chapter
Mutation and Variation
Chapter
The red blood cell in health and disease
Andrew Blann and Pam Holtom
This chapter illustrates the structure and function of the red cell and how it is adapted for its purpose of carrying oxygen. It considers the morphology of the cell and interrelationships between size, shape, and colour. The chapter highlights key aspects of the cell biology and molecular genetics of erythropoiesis and of haemoglobin generation. It discusses how the red cell operates in health and in disease, noting that the principal disease associated with the red blood cell is anaemia. The chapter lists the different types of haemoglobin and explains the relationship between their structure and function. It clarifies the importance of red blood cell enzymes and metabolic intermediates, including the aetiology and consequences of polycythaemia vera and erythrocytosis.
Chapter
Vertebrate development I: life cycles and experimental techniques
This chapter explores similarities and differences in the development of frogs, birds, fish, and mammals. It also looks into experimental approaches which investigate vertebrate development using Xenopus, zebrafish, chick, and mouse as models. The chapter refers here to transgenic techniques which are used to produce mutations with specific genes as an example. Additionally, the chapter notes how all vertebrates have a similar basic body plan with defining structures such as the spinal cord and skull. It shows the similarity between a mouse and a human in terms of early development. The chapter also links approaches used in investigating human embryonic development. Techniques for interfering with development can be broadly divided between experimental embryological techniques and genetics-based techniques.
Chapter
What’s the Evidence?
This chapter examines the evidence for evolution that we can see through looking at fossils, anatomy, biochemistry, ecological genetics, and genomics. Fossils are the most familiar evidence for evolution since they gave proof of life in the past geological ages. Anatomy studies the structure of living organisms and its comparison to other groups of organisms gives clues to evolutionary relationships. The science of biochemistry depends on the development of tools and techniques that spark new insights into the natural world. Genomics, on the other hand, showcases the formation of species such as DNA. The chapter also gives an overview of developmental biology which capitalizes on the emergence of genomics.
Chapter
The future of glycobiology
This chapter reflects on the future of glycobiology, considering biochemistry, cell biology, genetics, glycomics, and genomics. While the general question ‘What is the function of glycosylation?’ has probably been answered satisfactorily, specific questions of the form ‘What is the function of this particular glycan on this particular glycoconjugate?’ will be the basis for future work. A great deal has been learned about the roles of glycans, but there are also many indications that glycans have functions that we do not yet understand. A range of approaches, from glycan and lectin structure analysis to the physiological study of knockout mice, will be needed to provide convincing evidence for these roles. As our understanding of glycobiology broadens to encompass more examples, new routes to the application of this knowledge in the diagnosis and treatment of disease will undoubtedly emerge.
Chapter
Conservation genetics
The chapter looks into conservation genetics as a method used to mitigate extinction. It explains how molecular genetics is used in conservation biology. Molecular systemics are great assets in wildlife forensic investigations. PCR technology enables genetic studies to be conducted on rare species. The chapter notes careful evaluation is needed as neutral estimates of genetic diversity sometimes differ from measures of adaptive variation. Next, the chapter explores the basis and impact of inbreeding and captive breeding in relation to the genetic load of smaller populations. The chapter expounds on the concept of plant and animal conservations as well. De-extinction, meanwhile, is regarded as only a movie concept.
Chapter
Working with Genes: Analysing and Manipulating DNA
This chapter explores the process of analysing and manipulating deoxyribonucleic acid (DNA). A wide range of molecular biology techniques enables DNA to be manipulated and analysed, yielding information about the nature and function of genes. The terms recombinant DNA technology, DNA cloning, and gene cloning all refer to the same process, namely the transfer of a DNA fragment from one organism to a self-replicating genetic element that replicates the fragment in a foreign host cell. Multiple copies of a DNA sequence can be produced by cloning or by using the polymerase chain reaction. Genes are isolated from DNA libraries and gel electrophoresis separates different-sized DNA fragments. Meanwhile, the nucleotide sequence of a segment of DNA is determined by Frederick Sanger’s dideoxy method or next generation sequencing methods. Finally, forward and reverse genetics are different analytical approaches to linking phenotype and genotype.
Chapter
Mendelian Genetics
This chapter examines the study of Mendelian genetics. It shows how genetically determined traits are transmitted in sexually reproducing eukaryotes from one generation to the next. It then considers the organization of genes and chromosomes in sexually reproducing eukaryotes. The experiments of Gregor Mendel established the laws of inheritance involving phenotypes and genotypes. They also showed how genes for different traits segregate independently through either mitosis or meiosis. The chapter considers the extensions and refinements of Mendel's laws, which include genetic heterogeneity and pleiotropy. It explains how human inheritance also covers the incidence of genetic diseases that run within families.
Book
Jon Scott, Gus Cameron, Anne Goodenough, Dawn Hawkins, Jenny Koenig, Martin Luck, Despo Papachristodoulou, Alison Snape, Kay Yeoman, and Mark Goodwin
Biological Science: Exploring the Science of Life spans the full scale of biological science — from molecule to ecosystem. The first part of the text looks at life and its exploration. Topics covered in this section include exploring the science of life, the emergence of life on earth, defining life, evolutionary processes, and the diversity and organisation of life. Here, classification of life is also dealt with. The next section moves on to quantitative toolkits. Here, the text showcases nine toolkits which look at understanding data, size and scale, describing data, ratio and proportion, understanding samples, designing experiments, assessing patterns, formulae and equations, and rates of changes. Thereafter there are five modules. The first module is about life at the molecular level. Topics here include genetics, genomes, proteins, metabolism, and molecular tools. The second module looks at life at the cellular level. Here the text examines cell division, microbial diversity, microbes in life, and viruses. Module 3 is about the human organism and looks in detail at tissues, organs, and systems. The fourth module covers organismal diversity and describes structure, adaptation, and survival. The text finishes with a fifth module which looks at organism in their environments. Here, the chapters turn to ecology, evolution, genes, populations, communities, and ecosystems.
Chapter
Small population management
This chapter focuses on small population management. It starts by examining the concept behind reproductive biology and then discusses genetics and endocrinology. Next, the chapter look at various relationships between animals such as mating systems, breeding, and parenting, while exploring the issues and constraints on reproduction in captivity. It notes behaviour competence as a way to describe the ability of an animal to express appropriate behaviour in a given situation. It then explains the process of monitoring the reproductive status of animals in captivity by referencing invasive and non-invasive methods. It looks at the usage of reproductive technology to help with animal reproduction such as artificial insemination (AI), in vitro fertilization (IVF), and embryo transfer. Additionally, the chapter tackles how to manipulate the reproduction of exotic animals.
Book
Arthur M. Lesk
Introduction to Bioinformatics starts off by introducing the topic. It then looks at genetics and genomes. It moves on to consider the panorama of life. The text also considers alignments and phylogenetic trees. There is a chapter on structural bioinformatics and drug discovery. The text also examines scientific publications and archives, particularly media, content, access, and presentation. Artificial intelligence is considered as well, in addition to machine learning. There is an introduction to systems biology that follows towards the end. The book's final chapters look at metabolic pathways and control of organization.
Chapter
Molecular ecology: roots and branches
This chapter looks into molecular ecology. First, it introduces ecology as the scientific study of organisms' distribution and abundance before defining molecular ecology as the application of molecular genetic methods. The aim is to address ecological questions. The chapter explains the theory of evolution by natural selection which has been used as a vital framework in modern biology. It considers neutral theory and notes random genetic drift. Both of these discoveries increased the understanding of evolution. They look into the levels of polymorphism found in nature. The chapter illustrates the history and progress of molecular ecology and cites its links to technology, species identification, and genetic markers. It mentions how ecological genomics is exploring the workings of genetics in wild populations exposed to environmental variation.
Book
Graham Rowe, Michael Sweet, and Trevor J. C. Beebee
An Introduction to Molecular Ecology first introduces the topic by looking at roots and branches, molecular biology for ecologists, and molecular tools for molecular ecologists. Next, chapters turn to the next generation sequencing, species, populations, and individuals. Chapters also look at behavioural ecology and population genetics. The text also covers neutral and adaptive molecular variation, phytogeography, and conservation genetics. Finally, chapters look at microbial ecology, metagenomics, genomes, and genomics.
Chapter
Population genetics
This chapter focuses on the field of evolutionary biology in relation to changing distributions and frequencies of alleles within populations. This is called population genetics. The chapter looks into genetic diversity in natural populations and population size. The chapter highlights the importance of population bottlenecks. This is considered as a radical reduction in population size accompanied by the loss of genetic diversity. The chapter cites population structure and marker selection as important in the study of population subdivisions. Metapopulation is defined as the population of subpopulations with numerous genetic interconnectivities. The chapter also looks into the genetic estimation of gene flow and migration rate while looking into the identification of immigrant species. Additionally, it expounds on the molecular markers in terms of population genetics.
Book
Jon Scott, Gus Cameron, Anne Goodenough, Dawn Hawkins, Jenny Koenig, Martin Luck, Despo Papachristodoulou, Alison Snape, Kay Yeoman, and Mark Goodwin
Biological Science: Exploring the Science of Life spans the full scale of biological science — from molecule to ecosystem. The first part of the text looks at life and its exploration. Topics covered in this section include exploring the science of life, the emergence of life on earth, defining life, evolutionary processes, and the diversity and organisation of life. Here, classification of life is also dealt with. The next section moves on to quantitative toolkits. Here, the text showcases nine toolkits which look at understanding data, size and scale, describing data, ratio and proportion, understanding samples, designing experiments, assessing patterns, formulae and equations, and rates of changes. Thereafter there are five modules. The first module is about life at the molecular level. Topics here include genetics, genomes, proteins, metabolism, and molecular tools. The second module looks at life at the cellular level. Here the text examines cell division, microbial diversity, microbes in life, and viruses. Module 3 is about the human organism and looks in detail at tissues, organs, and systems. The fourth module covers organismal diversity and describes structure, adaptation, and survival. The text finishes with a fifth module which looks at organism in their environments. Here, the chapters turn to ecology, evolution, genes, populations, communities, and ecosystems.
Chapter
Mendelian Genetics
This chapter examines the study of Mendelian genetics. It shows how genetically determined traits are transmitted in sexually reproducing eukaryotes from one generation to the next. It then considers the organization of genes and chromosomes in sexually reproducing eukaryotes. The experiments of Gregor Mendel established the laws of inheritance involving phenotypes and genotypes. They also showed how genes for different traits segregate independently through either mitosis or meiosis. The chapter considers the extensions and refinements of Mendel's laws, which include genetic heterogeneity and pleiotropy. It explains how human inheritance also covers the incidence of genetic diseases that run within families.
Chapter
Principles of Mendelian Inheritance
This chapter examines the principles of Mendelian genetics, which is concerned with patterns of inheritance associated with one or a few genes. Monohybrid crosses investigate the genetic basis of traits determined by a single gene. Meanwhile, dihybrid crosses consider the inheritance patterns produced by the segregation of alleles of two genes. An individual possesses two alleles for each gene, which may be similar or different. Alleles segregate into gametes during meiosis. Next, the chapter looks at the relationship between probability and Mendelian genetics. The chi-squared statistical test is used in Mendelian genetics to compare observed progeny numbers with expected ratios, because the ratios of different progeny phenotypes can be informative of underlying genetics.
Chapter
The Genetics of Bacteria, Viruses, and Organelles
This chapter assesses the genetics of bacteria, viruses, and organelles. It begins by looking at the bacterial genome; most bacteria have a single circular chromosome, several million nucleotides in length. Bacteria and viruses have small haploid genomes. They are well suited to genetic studies because they have high rates of reproduction and produce large numbers of progeny. Plasmids are often present in bacterial cytoplasm. The chapter then considers how DNA can be transferred between bacterial cells by conjugation, transformation, or transduction. Viruses have DNA or RNA genomes. Bacteriophages are DNA viruses that infect bacteria, while retroviruses are RNA viruses that infect eukaryotic cells. Mitochondria and chloroplasts have their own genetic systems.
Chapter
The Genetics of Populations
This chapter delves into population genetics with a human focus and explores the assumptions of the Hardy—Weinberg equilibrium model. It reviews the many different types of evolutionary change which can operate in order to shape the genetic structure of a population and the imprints these leave at the level of the genome. It also features long-term studies of bacterial populations presented as a method to explore evolution experimentally. The chapter describes how transmission of alleles and genotypes within a population can be assessed, even when the individual matings cannot be monitored. It defines non-random mating as the main process that affects genotype frequencies without affecting allele frequencies directly, which can result in population stratification.
Chapter
Behavioral Genetics
This chapter focuses on behavioral genetics, which looks into how genes and the environment contribute to differences in behavioral phenotypic value. The heritability of a trait is proportionate to phenotypic variations and genetic influences. Additive, dominance, and epistatic effects are genetic factors affecting phenotypic variations. The knockout technique gives an understanding of how genetic variation is associated with behavioral variation by disabling a gene and examining its effect on behavior. The chapter also explains environment influences behavior through gene expression, while the genomic approach correlates gene expression with behavioral phenotypes. Additionally, the chapter notes that genes can restrict behavioral flexibility.
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