This paper provides an in-depth investigation of animal genetics. It begins with a general introduction the topic and a variety of subtopics that may be explored when considering animal genetics. The next section of the paper provides an overview of the basic molecular mechanisms through which animal genetics operate. The third section of the paper discusses the consequences of changes in animal genetics, focusing specifically on natural selection. The fourth section of the paper highlights some of the similarities and differences between the genetics of different animal species. The fifth section of the paper discusses the application of animal genetics to the prominent field of animal breeding. Finally, in the last section of the paper, animal genetics are discussed in the context of biological research. This includes a discussion of both the benefits and drawbacks of using animal models for biological research. Overall, it is clear that animal genetics is a relevant topic within the field of biology.
The biological kingdom Animalia contains organisms with a wide range of characteristics. From massive blue whales to tiny hummingbirds, and from slow-moving sloths to swift cheetahs, animals have a wide range of characteristics. These characteristics are determined by animal genetics. When considering the broad field of animal genetics, it is important to discuss the basic molecular mechanisms of animal genetics, the consequences of changes in animal genetics, the similarities and differences between the genetics of different animal species, the application of animal genetics in animal breeding, and the considerations that must be made when using animals for genetics research. By conducting an in-depth investigation of animal genetics, it is possible to gain valuable insight into the animal kingdom and the effects of animal genetics on the world today.
Basic Molecular Mechanisms of Animal Genetics
As in all other organisms, the basic genetic material in animals is DNA. Animals are eukaryotes, which means that they have a more complex genome than prokaryotes like bacteria (Cooper, 2000). In every animal cell, the DNA is stored in the nucleus, and every cell contains a complete copy of the genome. Within the DNA, there are genes, which are segments of DNA that yield functional products: either polypeptides or RNA (Cooper, 2000). The two processes involved in the production of functional products from animal genes are transcription and translation (Cooper, 2000). During transcription, the base pairs of the DNA serve as a template for the production of an RNA strand (Venters & Pugh, 2010). This strand may become a functional RNA product, or it may serve as a template in the process of translation. In the process of translation, a polypeptide chain made up of amino acids is produced based on the nucleotide sequence of an RNA chain (Venters & Pugh, 2000). Both transcription and translation are highly regulated processes. There are a wide range of factors that determine when each gene is translated, and how much is produced, over the course of an animal’s lifetime (Cooper, 2000). The expression of genes in animals determines every aspect of their physiology.
Consequences of Genetic Changes in Animals
Changes in animal DNA are known as mutations, and they may or may not have an effect on the individual in which they arise. Some “silent” mutations, such as those in introns, may have no impact on the function of an animal cell (Griffiths et al., 2000). Others can lead to changes in gene expression, including which genes are expressed, when they are expressed, and how much of a functional product is produced (Griffiths et al., 2000). When genetic changes affect inherited animal traits that contribute to or detract from the animal’s ability to survive or reproduce in a specific environment, the genetic change may be selected for over time (University of Hawaii, 2017). This process, known as natural selection, can lead to certain animal traits – such as the shape of a bird’s beak or the color of a fish – being favored over others in an animal population (University of Hawaii, 2017). Natural selection is the mechanism through which evolution operates (University of Hawaii, 2017). The process can lead to physical and behavioral changes within an animal species, and it can also cause new animal species to arise over time (University of Hawaii, 2017).
Similarities and Differences in the Genetics of Animal Species
All animals share certain genetic characteristics, which indicates that they all arose from a common ancestor in the past that possessed all of these genes (Alberts et al., 2002). Significantly, almost all animals share a basic set of genes that control development (Alberts et al., 2002). As a result, even though scientists do not know exactly what the common ancestor of animals looked like, they have been able to determine some of its basic features, based on the way developmental genes work (Alberts et al., 2002). These basic features include a protective outer layer made up of epidermal cells, an internal gut to absorb nutrients from food, muscle cells required for movement, and neural cells to control body movements (Alberts et al., 2002). Today, because most animals have this basic set of genes, they all have these basic features, and they are differentiated by other genes that vary between species.
One of the most noticeable differences between animal genomes is that different species have different chromosome numbers (University of Illinois, n.d.). Chromosomes are the organizational framework in which DNA is stored within the nucleus (Cooper, 2000), and they vary between animals species. Somatic cells are diploid, which means that each cell has a pair of chromosomes, while haploid cells only have one set of chromosomes (University of Illinois, n.d.). Humans have 23 pairs of chromosomes, while cats have 38, horses have 64, chimpanzees have 24, and moths have 112 (University of Illinois, n.d.; UCSB, 2017). It is important to note that an animal’s chromosome number is not related to its complexity (UCSB, 2017). Also, some animals share a chromosome number (UCSB, 2017). For example, both humans and a subspecies of Muntiacusmuntjac (a small deer) have 23 pairs of chromosomes (UCSB, 2017).
Applications of Animal Genetics in Animal Breeding
One of the most prominent applications of animal genetics in the world today is in animal breeding. Humans have practiced animal breeding for thousands of years (Flint & Woolliams, 2008). Although the term was originally associated with the artificial selection of certain traits for agricultural purposes – such as selecting for food animals that produce more meat or work animals that are stronger – it is now encompasses the breeding of animals for any purpose – such as for pets or for medical or scientific research (Woolliams & Flint, 2008). In animal breeding, humans select for certain traits that they prefer for their specific purpose (Woolliams & Flint, 2008). In this way, animal breeding is similar to natural selection, but the reason that certain heritable traits are selected for over others is human preference, rather than environmental forces. In recent years, significant advances in human knowledge of animal genetics have led to the development of genetic technologies that support more effective animal breeding (Woolliams & Flint, 2008).
Conducting Genetics Research with Animals
One of the purposes of animal breeding is for biological research. In biological research today, animal models are commonly used to study human disease and genetic concepts (Simmons, 2008). Research on animal models can be produce insights about human genetics and diseases due to the presence of homologous genes in animals (Berkeley, n.d.). A homolog is a gene shared by two different animal species that was derived from a DNA sequence in a common ancestor (Berkeley, n.d.). These genes may be identified based on their sequence similarity, and sometimes, they produce symptoms in animal models that are similar to those commonly observed in humans (Simmons, 2008). However, it is important to note that genetic differences between animals can prevent research on one animal species, such as mice, from being directly translatable to conditions in another species, such as humans (Simmons, 2008).
In conclusion, understanding animal genetics requires an exploration of genetic principles at the molecular, cellular, and organismal levels. By examining the basic molecular mechanisms of animal genetics, comparing the genetic characteristics of animal species, and discussing the forces of natural selection and evolution, it is possible to get an idea of how animal genetics are manifested in the real world. It is also important to consider the role of animal genetics in animal breeding, as well as the way in which the principles of animal genetics have been harnessed by medical researchers to conduct innovative research in the biological sciences.
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