What is Life?

Introduction to Modern Biology I.

Péter Molnár, Zoology, Univ. West Hungary, Szombathely

Mader: Inquiry into LifeSilbernagi: Color atlas of Physiology

How to define life?

Could Other life-forms exist? Could we recognize it?

How life developed on Earth? – Arrived from space, developed on other planets?

Can we make life? Living organisms? Humans?

Will computers / softwares ever evolve into living things?

The first synthetic cellD G Gibson et al, Science, 2010, DOI: 10.1126/science.1190719

A semi-synthetic organism with an expanded genetic alphabetD. A. Malyshev et al. Nature 509, 385–388 (15 May 2014)

Living Things Are Organized

Acquire Materials and Energy

Homeostatic

Respond to Stimuli

Reproduce

Things Grow and Develop

Adapted

Evolution, which has been going on since the origin of life, explains both the unity and the diversity of life. All organisms share the same characteristics of life because their ancestry can be traced to the first cell or cells. Organisms are diverse because they are adapted to different ways of life. Are computers alive?

http://thesciencenetwork.org/programs/the-great-debate-what-is-life/what-is-life-panel

https://www.youtube.com/watch?v=3w1fY67dnFI Biology Lecture - 1 - Introduction to Biology

https://www.youtube.com/watch?v=zcHBT6QFIqk Biology Lecture - 2 - What is Life?

https://www.youtube.com/watch?v=1tWuDkrvJ6k Biology Lecture - 3 - Properties of Life

http://www.ted.com/talks/martin_hanczyc_the_line_between_life_and_not_life

Origin of life

http://en.wikipedia.org/wiki/Abiogenesis

https://www.youtube.com/watch?v=W3ceg--uQKM Abiogenesis

http://www.powershow.com/view/3d0c7-NWY1N/How_To_Study_The_Origin_of_Life_On_Earth_powerpoint_ppt_presentation

Where life come from?

This high-resolution scanning electron microscope image shows an unusual tube-like structure that is less than 1/100th the width of a human hair in size found in meteorite ALH84001. Credit: NASA

The general consensus now is that the original rock formed 4 billion years ago on Mars. It was eventually catapulted into space by an impact and wandered the solar system for millions of years before landing on Earth 13,000 years ago.Over 50 other meteorites have been identified as coming from Mars, but ALH84001 is by far the oldest, with the next in age being just 1.3 billion years old. http://www.astrobio.net/news-exclusive/the-continuing-controversy-of-the-mars-

meteorite/

https://www.youtube.com/watch?v=ofFhHcvasHA

Professor Steven Benner, a geochemist, has argued that the "seeds" of life probably arrived on Earth in meteorites blasted off Mars by impacts or volcanic eruptions. As evidence, he points to the oxidised mineral form of the element molybdenum, thought to be a catalyst that helped organic molecules develop into the first living structures.

Homework: Collect data on extreme life forms, which could survive space travel