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Announcements for Nematology 10V (updated March 25, 2016)

What Does It Mean to Be Alive?

Introduction to this section:

Reading:
ARE VIRUSES ALIVE? NEW EVIDENCE SAYS YES

Video 1: Characteristics of Life (2:08)

Video 2: The Definition of Life - Star Trek TNG (4:50)

Summary/Study Guide:
The 7 Characteristics of all Living things: 1) They grow and develop. 2) They are able to reproduce, the process by which living things give rise to offspring. 3) They detect changes in their environment and they respond to them. 4) They use energy. 5) They maintain a constant internal environment through homeostasis. 6) They have cellular organization. 7) They are able to adapt, evolve, and pass on their genetic information in the form of DNA. All forms of life are built of cells. A cell is the basic unit of the structure and function of living things.

Historically, scientists have not considered viruses to be alive. A new study analyzes the distinct, three-dimensional structures found in proteins. These structures are called folds. The interesting thing about these results is that they indicate that viruses must have diversified from ancient cells by a process called reductive evolution, where organisms simplify instead of becoming more complex. Viruses were likely more cellular in nature and existed in the form of primitive cells.

Sources:
Video 1: Characteristics of Life, https://www.youtube.com/watch?v=0NnFhY_STFQ
Video 2: The Definition of Life - Star Trek TNG, https://www.youtube.com/watch?v=5OfIsNPZm8w