Module 6

1. Module 6

1.6. Page 4

Lesson 1

Module 6—Mendelian Genetics: The Transmission of Traits to the Next Generation

Reflect and Connect

Study Dictionary or Flash Card Set

Learning to communicate in another country would be challenging without knowledge of a few terms in the local vocabulary. Working in genetics is much the same. To help you in your study of genetics, there are many terms that you need to understand. Using the new terms identified by the bold type in your textbook and in the lesson, create a flash card study set. This could be in the form of a PowerPoint presentation, an online flash card set, or a traditional 3 x 5 paper card stack. Write the term on one side and the definition on the other. You may choose to include examples because they are often helpful in illustrating a concept.

You will use your flash card set to review and study the vocabulary of each lesson as you work through the module.

Submit your work to your teacher for assessment before filing your work in your course folder. Your flash cards will be assessed according to the following rubric:

Rubric

	4 marks	3 marks	2 marks	1 mark
Quantity	Set has more than 10 cards	Set has 8 to 10 cards	Set has 5 to 7 cards	Set has less than 5 cards
Usefulness	Can be used for study and shared with others	Can be used for study or shared with others	Appears on one page or cannot easily be mixed up or changed	Is a simple list of terms and definitions
Quality of Definitions	All terms are uniquely defined and clear	Most definitions are clear	Many definitions require understanding of many other genetic terms	Most definitions are copied from the text glossary

Going Beyond

Write a fictional story while attempting to incorporate as many of your new vocabulary words as possible. After your first draft, complete a revision to add the words that you did not use in your original draft. Save your story to your course folder and post it to your class discussion area.

Self-Check

To apply your understanding of Mendelian genetics, answer the following Diploma-Exam-style questions.

Ideas concerning the nature of inheritance have very early origins, but the conceptual breakthrough that established modern genetics as a science was made less than 150 years ago by an Austrian monk, Gregor Mendel.

SC 8. Alternate forms of the same gene are known as

alleles
gametes
genotypes
heterozygotes

SC 9. Mendel’s principle of segregation states that alternate forms of a gene separate during

fertilization
seed dispersal
cross-pollination
gamete formation

SC 10. An organism is heterozygous for two pairs of genes. The number of different combinations of alleles that can form for these two genes in the organism’s gametes is

Use the following information about tobiano twin colts to answer the next question.

Descriptions and Symbols Used to Represent One Type of Coat Colour in Horses

1	2	3	4
DNA sequence for coat colour	TT, Tt	T	Tobiano (white spotting pattern)
	tt	t	Not tobiano (no white spotting pattern)

Numerical Response

SC 11. Using the numbers above, match these descriptions and symbols with the term below to which they apply.

Description or Symbol Number:
	_____	_____	_____	_____
Term:
	gene	allele	phenotype	genotype

Check your answers.

Try This Answers

SC 8. A

SC 9. D

SC 10. C

SC 11. 1, 3, 4, 2

Reflect on the Big Picture

You are developing some understanding of why you may look like someone else in your family. You may be better able to explain why you have your mother’s eyes, or your grandfather’s hairline, but there is still much to come in genetics! The determination of human eye colour is much more complicated than the simple principles developed by Mendel.

For thousands of years, people bred their livestock and plants hoping to establish desirable characteristics in the next generation. Their attempts weren’t always successful. Not until the 1850s did scientific discoveries lead to an understanding of just how these characteristics were passed from one generation to the next. Gregor Mendel, the “Father of Genetics,” was the first major contributor to these discoveries.

By examining the work of Gregor Mendel, you should now have begun to understand how one trait is passed on to the next generation. Some of them are part of a dominant/recessive pair as in Mendel’s peas. The concept of dominant alleles explains why you may show many of the same traits that you see in your parents. The concept of recessive alleles helps you understand why you may show some traits seen in your grandparents but not in your parents.

Human cells have thousands of alleles. They are not always simply dominant or recessive. As you will discover in the following lessons, there are many ways characteristics are inherited.

Module 6: Lesson 1 Assignment

Submit your flash cards to your teacher for assessment.