Lesson 8.1 - Geologic Change

Welcome back!

Did you ever wonder why more people seem to have brown eyes compared to blue eyes? Or why people who are related look like each other. Well, it all comes down to the instructions – the DNA. Every organism living today, from pea plants to people, inherited their traits or unique features from their ancestors. In other words, your looks and even aspects of your personality, have been “donated” to you by your parents. Of course, it doesn’t end there. Your parents got their traits from your grandparents, and your grandparents got theirs from your great-grandparents, and your great-grandparents got their traits from your great-great-grandparents, and on and on… You are but the tip of the branch on your family tree. The latest version, so to speak. The next link in a chain that goes back millions and millions of years.

This process of passing traits from parents to their children (or offspring) is called heredity, and some of its most fundamental secrets where discovered by a man named Gregor Mendel in the mid-1800s. Like many who make significant scientific discoveries, Mendel wasn’t looking for what he found. In fact, Mendel wasn’t even a scientist - he was a monk. A monk who loved to grow a garden, had a knack for math, and was a very, very patient man. Mendel conducted thousands of experiments growing and breeding pea plants. He always made sure to take careful notes on what the resulting offspring looked like. Over time Mendel noticed that some traits or characteristic always showed up more than other traits. He called these stronger traits the dominant traits, and the traits that seemed to disappear the recessive traits. Through his experiments breeding pea plants, Gregor Mendel stumbled upon the secret rules to how genetic information is passed on between one generation and the next. And these rules, as scientist would later learn, not only applied to pea plants, but to other living organisms as well…including us!

By the end of this lesson, you should be able to define heredity, and describe the experiments conducted by Gregor Mendel.

Consider the following questions while you are working through the lesson:

Why do people look and behave differently? Why did Gregor Mendel use pea plants to study how traits are inherited? How can you determine if a flower is self-pollinating? Explain what would have happened if Gregor Mendel hadn’t removed the anthers from one of his pea plant flowers? Compare and contrast dominant and recessive traits? Why do certain traits reappear in the second-generation offspring?

What's the Big Idea?

Now it's time to answer the following "Big Idea" prompt(s) for this lesson. In order to receive credit for your response you must: (1) reach the minimum word count, and (2) include appropritate key terms.

Remember, you are welcome to use your notes to help you write your response.

Big Idea Idea Questions:

Compare and contrast the principles of uniformitarianism and catastrophism. Please be sure to provide examples of each principle.

Minimum Length: 25