Lamarck described that living beings acquired traits during the course of their lives based on the needs of the organism, and these traits could then be passed on to the offspring of the organism. For example, according to Lamarckism, a giraffe has a long neck because initially, the giraffe wished for a long neck in order to feed on tall plants, and over the course of the giraffe’s life, its neck progressively lengthened as a result. This “change” would then be passed onto the giraffe’s offspring, and the offspring would continue where their parent(s) left off until they had long enough necks to feed. The theory that Lamarck proposed is incorrect as it suggested that the traits were initially “acquired” during the life the organism and were
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How were the ancestors affected by a boy experiencing starvation between the ages of 9 - 11?
Ans: In the case of the boys that experienced starvation between the ages of 9 to 11, it was observed that the grandchildren of those boys suffered from a much lower risk of heart disease (about 1/4th) and diabetes than normal. Thus, the grandchildren of the starved boys also enjoyed extended lifespans, sometimes by as much as 30 years.
2. What inheritable effect do they think the boy’s starvation had on his body?
Ans: The starvation most likely caused modifications of the DNA, such as methylation, phosphorylation, etc., in precursor sperm cells of the starving boys, which probably prevented the transcription, and thus translation of DNA and Protein involved in heart disease and diabetes. This probably led to offspring of the starving boys to have a reduced risk of disease and increased …show more content…
In both stories, there is either an environmental factor or a behavioral factor that alters the expression of the genome. In the case of the rats, pups that are licked, show expression of the “Maternal Care Gene” which is normally inhibited in pups that are not licked (by means of DNA methylation). Licking increases serotonin in the brains of the pups and removes the methylation of the DNA, which allows for expression of the “Maternal Care Gene”. Thus, based on whether the pups are licked or not, they will, in turn, lick their kids or not. In the case of the starvation and well-fed boys, depending on whether the boys were starved or well-fed between the ages of 9 to 11, the grandchildren of the boys either had a decreased risk of heart disease and diabetes, or an increased risk. In this case, being starved at a young age led to the under-expression of genes involved in heart disease and diabetes, in precursor sperm cells, whereas being well-fed at a young age led to the over-expression of the genes involved in heart disease and diabetes, in precursor sperm cells. Thus, both stories demonstrated that behavior and environment could affect the expression of
How were the ancestors affected by a boy experiencing starvation between the ages of 9 - 11?
Ans: In the case of the boys that experienced starvation between the ages of 9 to 11, it was observed that the grandchildren of those boys suffered from a much lower risk of heart disease (about 1/4th) and diabetes than normal. Thus, the grandchildren of the starved boys also enjoyed extended lifespans, sometimes by as much as 30 years.
2. What inheritable effect do they think the boy’s starvation had on his body?
Ans: The starvation most likely caused modifications of the DNA, such as methylation, phosphorylation, etc., in precursor sperm cells of the starving boys, which probably prevented the transcription, and thus translation of DNA and Protein involved in heart disease and diabetes. This probably led to offspring of the starving boys to have a reduced risk of disease and increased …show more content…
In both stories, there is either an environmental factor or a behavioral factor that alters the expression of the genome. In the case of the rats, pups that are licked, show expression of the “Maternal Care Gene” which is normally inhibited in pups that are not licked (by means of DNA methylation). Licking increases serotonin in the brains of the pups and removes the methylation of the DNA, which allows for expression of the “Maternal Care Gene”. Thus, based on whether the pups are licked or not, they will, in turn, lick their kids or not. In the case of the starvation and well-fed boys, depending on whether the boys were starved or well-fed between the ages of 9 to 11, the grandchildren of the boys either had a decreased risk of heart disease and diabetes, or an increased risk. In this case, being starved at a young age led to the under-expression of genes involved in heart disease and diabetes, in precursor sperm cells, whereas being well-fed at a young age led to the over-expression of the genes involved in heart disease and diabetes, in precursor sperm cells. Thus, both stories demonstrated that behavior and environment could affect the expression of