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B6 J) Selective Breeding
B6 J) Selective Breeding
We can selectively breed organisms so that the offspring have more desirable characteristics. For example, we can selectively breed cows to produce a high quantity of high quality meat.
We can also selectively breed dogs for either looks or for function. For example, guard dogs have been selectively bred so that they are strong, large, aggressive on command and intelligent. Also, sausage dogs have been selectively bred to have a long body, cute face and little legs.
Furthermore, we can selectively breed plants. This can be for looks, such as flowers of a particular shape or colour. Or, so that we can produce crops that have a higher yield or are resistant to a particular disease.
We can also selectively breed dogs for either looks or for function. For example, guard dogs have been selectively bred so that they are strong, large, aggressive on command and intelligent. Also, sausage dogs have been selectively bred to have a long body, cute face and little legs.
Furthermore, we can selectively breed plants. This can be for looks, such as flowers of a particular shape or colour. Or, so that we can produce crops that have a higher yield or are resistant to a particular disease.
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How does Selective Breeding Work?
Selective breeding always follows the same process. The first step is to select two individuals with desirable characteristics. We then breed them with each other which results in a variety of offspring with a range of characteristics; some of the offspring will have the desired characteristics and other offspring won’t have the desired characteristics. We then choose the best offspring and breed from them, which results in a variety of offspring. We then choose the best offspring and breed from them etc. This selection and breeding process repeats itself over and over again, which leads to the desirable characteristics becoming stronger in the population. In selective breeding, we do not breed from offspring that do not have the desired characteristics.
Let’s now have a look at the selective breeding of cows to produce a high quantity of high quality meat. The first step is to choose two cows where one produces high quality meat, and the other produces a high quantity of meat. We then breed these two individuals, which results in a variety of offspring with different characteristics. We review the offspring and select the offspring with the best characteristics to breed from; we select the offspring that produces a high quantity of high quality meat. We then repeat this selection and breeding process many times, which leads to the characteristics becoming stronger in the population; we have a population of cows that produces a high quantity of high quality meat.
Selective breeding always follows the same process. The first step is to select two individuals with desirable characteristics. We then breed them with each other which results in a variety of offspring with a range of characteristics; some of the offspring will have the desired characteristics and other offspring won’t have the desired characteristics. We then choose the best offspring and breed from them, which results in a variety of offspring. We then choose the best offspring and breed from them etc. This selection and breeding process repeats itself over and over again, which leads to the desirable characteristics becoming stronger in the population. In selective breeding, we do not breed from offspring that do not have the desired characteristics.
Let’s now have a look at the selective breeding of cows to produce a high quantity of high quality meat. The first step is to choose two cows where one produces high quality meat, and the other produces a high quantity of meat. We then breed these two individuals, which results in a variety of offspring with different characteristics. We review the offspring and select the offspring with the best characteristics to breed from; we select the offspring that produces a high quantity of high quality meat. We then repeat this selection and breeding process many times, which leads to the characteristics becoming stronger in the population; we have a population of cows that produces a high quantity of high quality meat.
We can also selectively breed plants so that they have desirable characteristics. For example, we can breed wheat plants that are resistant to a particular disease and produce a high yield (a high quantity of wheat). We do this by choosing two wheat plants with these desired characteristics. For example, one of the wheat plants that we will breed from will be resistant to the disease (and produce a small yield). The other wheat plant that we will breed from will produce a high yield (and not be resistant to the disease). We then breed the two wheat plants, which results in a range of offspring; some of the offspring will have the desired characteristics and others won’t. We then select the offspring with the best characteristics and breed from them. We repeat the selection and breeding process many times, which will result in a population of wheat that will be disease resistant and produce a high yield.
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Negatives of Selective Breeding
The main negative of selective breeding is that the offspring will have genes that are very similar to each other. This happens because the selective breeder will breed animals that are very closely related to one another – this is known as inbreeding. Inbreeding results in a reduction of what is known as the gene pool, which is the number of different alleles in a population (alleles are different versions of the same gene). A reduction in the gene pool can create harmful genetic health conditions. Selective breeding can also result in the breed being susceptible to certain diseases that may kill all or a high proportion of the population. This is because all of the offspring have genes that are very similar to each other, so if one of the offspring is killed by a disease, it is likely that all of the other offspring will also be killed by the disease. This is because there is less chance of any resistant alleles being present in a population with genes that are very closely related to one another.
The main negative of selective breeding is that the offspring will have genes that are very similar to each other. This happens because the selective breeder will breed animals that are very closely related to one another – this is known as inbreeding. Inbreeding results in a reduction of what is known as the gene pool, which is the number of different alleles in a population (alleles are different versions of the same gene). A reduction in the gene pool can create harmful genetic health conditions. Selective breeding can also result in the breed being susceptible to certain diseases that may kill all or a high proportion of the population. This is because all of the offspring have genes that are very similar to each other, so if one of the offspring is killed by a disease, it is likely that all of the other offspring will also be killed by the disease. This is because there is less chance of any resistant alleles being present in a population with genes that are very closely related to one another.