Phenotype plasticity | Heredity | AP Biology | Khan Academy

TL;DR

NASA scientists studied identical twin astronauts to observe the effects of space travel on gene expression, revealing a 7% difference in gene expression due to the unique environment and stressors of space.

Transcript

• [Instructor] The folks you see in this picture are two NASA astronauts who also happen to be identical twins. On the left here, this is Mark Kelly, you can see his name on his patch right over there, and then this is Scott Kelly. And the reason why we want to look at these two astronauts in particular is to think about genotype and phenotype that... Read More

Key Insights

• 💁 Genotype refers to an organism's genetic information, while phenotype refers to the observable characteristics.
• 🧑‍🏭 Phenotype plasticity describes how the same genotype can result in variations of phenotype due to environmental factors.
• 👨‍🚀 Identical twin astronauts, Scott and Mark Kelly, were studied by NASA to examine the effects of space travel on gene expression and phenotypes.
• 😑 Scott Kelly's extended time in space resulted in a 7% difference in gene expression compared to his brother, Mark.
• 👾 Factors such as the space environment, low oxygen levels, high carbon dioxide levels, and stressors of space travel were theorized to have influenced gene expression and phenotypes.
• 🧑‍🏭 This study highlights the significance of environmental factors in shaping observable characteristics, even among individuals with identical genotypes.
• 🖐️ Phenotype plasticity plays a crucial role in understanding how organisms respond to and adapt to their environments.

Questions & Answers

Q: What is the difference between genotype and phenotype?

Genotype refers to an organism's actual genetic information encoded in its genes, while phenotype refers to the observable characteristics. Genotype is the blueprint, and phenotype is the end result of the interaction between genotype and the environment.

Q: What is phenotype plasticity?

Phenotype plasticity refers to the ability of the same genotype to result in variations of phenotype due to environmental factors. It shows that even individuals with the same genetic information can exhibit different observable characteristics.

Q: How did NASA study the effects of space travel on gene expression?

NASA studied identical twin astronauts, Scott and Mark Kelly. Scott spent an extended period of time in space, while Mark didn't. By comparing their gene expression before and after space travel, NASA observed differences that highlighted the impact of the space environment on gene expression.

Q: What were the findings of NASA's study on the Kelly twins?

NASA found a 7% difference in gene expression between Scott and Mark Kelly after Scott's extended time in space. The low oxygen environment, high carbon dioxide levels, and stressors of space travel were theorized to have influenced the gene expression and resulting phenotypes.

Summary & Key Takeaways

• Genotype refers to the actual genetic information encoded in an organism's genes, while phenotype refers to the observable characteristics. Phenotype plasticity describes how the same genotype can result in variations of phenotype due to environmental factors.

• Identical twin astronauts, Scott and Mark Kelly, served as subjects to study the effects of space travel on gene expression. Despite having the same genotype, their phenotypes differed due to their bodies developing in different environments.

• After an extended period of time in space, Scott Kelly's gene expression showed a 7% difference from his brother's, indicating the impact of the space environment on phenotype plasticity.