Extremophiles are organisms that are adapted to survive in extreme
environments. This lecture describes the challenges that
extremes of heat, cold, acidity, salinity, and radiation pose to
organisms, and show examples of how evolution has nonetheless allowed
some organisms to adapt to not just survive but thrive in such extreme
conditions. Finally, we wi ... Show More
Oct 2009
Lecture 15: The Chemistry of Life
What is the basic chemistry of living organisms? We introduce the requirements for metabolism (raw
materials and energy), the ATP/ADP energy cycle in cells, auto- and
heterotrophs, photosynthesis and chemosynthesis, and the role played by
liquid water. The goal of today's lecture ... Show More
45m 4s
Mar 2022
Comment calculer l'âge d'une étoile ?
La durée de vie d'une étoile peut nous renseigner sur sa composition et sur l'existence éventuelle de la vie dans le cosmos. mais, en dehors du Soleil, il est assez difficile de déterminer l'âge d'une étoile.
L'importance de la masse
En évaluant, grâce à la radioactivité, l'âge d ... Show More
1m 58s