Module 6
1. Module 6
1.32. Lesson 7
Module 6—Mendelian Genetics: The Transmission of Traits to the Next Generation
Lesson 7—Genes and the Environment
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Get Focused
Nature verses nurture. Have you heard the ongoing debate over which is the strongest influence on a person’s life? While this debate is more focused on innate qualities versus personal experiences, it has relevance in genetics too. Our environment can significantly influence our genes. Sun exposure triggers all kinds of genes to be expressed in plants and animals. Exposure to or lack of water can change the development of leaves in the same plants, particularly their expression of colour intensity. Changes in temperature cause the expression of dark pigment in some rabbits and in Siamese cats. These are very specific examples, but just how much the environment affects gene expression is open for discussion. In this lesson, you will explore the effect the environment may have on the expression of genes.
In this lesson, the following focusing question will be examined:
- How does the environment affect the expression of genes?
nature: in reference to the nature versus nurture debate, refers to the components of an individual’s phenotypes that are determined by his or her genes (e.g., approximately 50% of intelligence is thought to be due to nature)
nurture: refers to the component of one’s phenotypes that are determined by one’s environment
innate: a characteristic one is born with
environment: all non-genetic factors that affect a person’s characteristics (e.g., how he or she was raised, light levels, friends, temperature, good and bad experiences, diet and nutrients available, and so on)
expression: refers to the transcription and translation of the gene to produce the requested protein
Whether or not an allele will be expressed is affected by whether or not the allele is dominant; whether the product is needed by the cell; the stage of the life cycle; and, to some degree, the environmental conditions. In undifferentiated cells, all genes are expressed; in differentiated cells only some genes are expressed.
Module 6: Lesson 7 Assignment
Your teacher-marked Module 6: Lesson 7 Assignment requires you to submit a response to the following:
- a lab on temperature and gender
The lab presents questions on nature versus nurture for assessment.
Download a copy of the Module 6: Lesson 7 Assignment to your computer now. You will receive further instructions on how to complete this assignment later in the lesson.
Continue to add to your flash cards.
You must decide what to do with the questions that are not marked by the teacher.
Remember that these questions provide you with the practice and feedback that you need to successfully complete this course. You should record the answers to all of the questions and place those answers in your course folder.
Remember you also have the option of trying additional questions from the textbook for further practice. Consult with your teacher for the answers to these questions. The Key will also provide you with many Diploma Exam-style multiple-choice, numerical-response, and written-response questions that will be an excellent review of the module. Practising your responses to these types of questions is good preparation for the Diploma Exam.