Lesson Purpose
With the appearance of the first planets, the Universe became much more complex. Planets, which formed from clouds of chemicals created during the death of stars, are more chemically diverse than the stars from which they came. Planets also differ from stars because they don't generate huge amounts of energy at their centres. As a result, their surface temperatures are much cooler. This combination of diverse chemical ingredients and less violent conditions enabled planets to become the setting for life. When life emerged on Earth, it had characteristics that made it very different from non-living things. Many people will tell you they 'know' the difference between living and non-living things. However, biologists - the experts - have struggled to agree on a single definition of life, even though many of the proposed definitions share similarities. In this lesson, we'll focus on understanding the characteristics all livings things share.
The outcomes of this lesson are: 1.) To describe the conditions that made it possible for life to emerge on Earth; 2.) To explain the differences between life and nonlife.
The outcomes of this lesson are: 1.) To describe the conditions that made it possible for life to emerge on Earth; 2.) To explain the differences between life and nonlife.
Activity 1 - The Driving Question Notebook
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Activity Objectives
This activity presents the driving question for Unit 5. It’s meant to help you stay focused on this question as you learn new material. Activity Tasks
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Activity 2 - A Big History of Everything H2
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Activity Objectives
This video introduces you to the emergence of life on Earth. Understanding how life emerged from nonlife can be confusing, and this video gives one explanation of how this process occurred, and what happened as life evolved. Activity Tasks
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The emergence of life on Earth is a truly amazing development in the history of the Universe. And the fact that a chemical reaction in the oceans eventually resulted in something as complex as ourselves is nearly mind-boggling. It’s no wonder that life is one of Big History’s thresholds of increasing complexity!
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Activity 3 - How Closely Related Are We?
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Activity Objectives
This activity helps you gain an understanding of the relationship between different species, and see how we (humans) are related to other species. The evolution of life from bacteria to humans is pretty hard for people to wrap their minds around, and showing connections among different species will help increase your understanding. Activity Tasks
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Activity 4 - The Origin of Life: Crash Course
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Activity Objectives
It’s not always easy to see the close connections humans share with other species. Sometimes, the connections are detectable only at the genetic level; but the connections are there, nonetheless. What is it that connects humans with other species? DNA is one important ingredient – after all, DNA is something that all living things share. There are other key characteristics that most living things share with each other and these are what make living organisms different from non-living. Activity Tasks
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DNA is the most important characteristic of all living things. It is essential to the story of life. Understanding the complexities of it are not essential to the Big History story; however, understanding its importance to life, is. Try not to get too bogged down in the details, especially since scientists are still trying to work out how this molecule became the master blueprint of all life on Earth.
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Activity 5 - "Life and Purpose"
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Activity Objectives
You will get an introduction to another way of defining what it means to be living. As you have already learned in the course, different scholars, especially those from different disciplines, may approach the same subject from a different angle, or use different words to describe the same thing. This is a great example of that process. Activity Tasks
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Activity 6 - Claim Testing: What is Life?
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Activity Objectives
You will use claim testers to firm up your understanding of the differences between life and nonlife. More and more research and writing is coming up in the course, and your claim-testing skills need to be well-developed so you’re ready for the upcoming work. Activity Tasks
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Challenge Yourself! - Optional Activities
1. Humans and chimpanzees are close cousins; we diverged from a common ancestor that lived around 7 million years ago.
2. “The most reliable joy is to be out of doors, to be a creature among other creatures. I find it very restful."
-Ursula Goodenough
2. “The most reliable joy is to be out of doors, to be a creature among other creatures. I find it very restful."
-Ursula Goodenough