Uploaded November 2020 | Updated September 2026, 2 weeks ago
What is life? A biologist tries to give a definition of life.
🔬 Subscribe for more awesome biomedical research: bit.ly/2SRMqhC
🔬Me being funny on other media:
Twitter: twitter.com/CSteinek
Discord: discord.gg/9VKnTSF
What is Life? It is quite difficult to give a short definition of life. However, we can try to define life by looking at some characteristics of life forms. Robert Hooke and Anton van Leeuwenhoek were the first ones to describe cells. Cells contain a variety of organelles which are enclosed by a membrane. In the 20th century, Erwin Schroedinger said in his book "What is life?" that life seems to defy the second law of thermodynamics. However, complex biochemistry and membranes help to overcome this law of physics. Besides having cells, life also has DNA or RNA which stores information to make a cell. All living organisms use DNA or RNA to make RNAs and proteins. Waddington stated that the regulation of DNA is necessary to decide cell fate. Many cells of our bodies have the same DNA but different sets of active genes. Organisms are also responsive and grow and develop through interactions with their environments. Moreover, life is also defined by reproduction. Through reproduction DNA can be passed down to future generations. Charles Darwin defined the process of evolution where mutations (genetic variations) lead to different reproductive successes through natural selection.
Viruses are often not considered to be alive as they are in great need of a host. Sir Paul Nurse, however, argues that they might be considered alive given that many organisms depend on other organisms. All in all, life is extraordinary.
Great inspirations:
"What is life?" by Erwin Schrödinger
"What is life?" by Sir Paul Nurse
Images:
Some pictures were derived from Servier Medical Art by Servier. You can find over 3000 free medical images here: smart.servier.com
Single Cell by Videezy, CCA 4.0
Biology by CNX OpenStax, CCA 4.0
SJ8&18-2 cells by AbdyMabbett (Carl Zeiss Microscopy), CCA 2.0
Francis Crick by Marc Lieberman, Materialscientist, CCA 2.5
Rosalind Franklin by MRC Laboratory of Molecular Biology, CC-BY 4.0
Wuthering Heights family tree by shako, CC-BY 3.0
Tree of life by Maulucioni, CC-BY 3.0
Fossil of Seymouria By Sanjay Acharya, CC-BY 4.0
Darwin Finches by the Wellcome Trust, CC-BY-4.0
Cellular Respiration by RegisFrey, CC-BY-3.0
Museo del Mamut by Thomas Quine, CC-BY 2.0
Way to Chirbasa by Dibendu Nandi, CC-BY 4.0
Sir Paul Nurse by the University of Exeter, CC-BY 2.0
Plasdomium falciparum by Calicut Medical College, CCA-BY 4.0
Music:
Title: No. 4 Piano Journey
Artist: Esther Abrami CCA
Title:Not For Nothing
Artist: Otis McDonald CCA
Title: Luminance
Artist: Scott Buckley soundcloud.com/scottbuckley (promoted by Audio Library youtu.be/yTl_PtnDwEY) CCA
About Clemens Steinek:
CLEMENS STEINEK is a postgraduate student/youtuber (LifeLabLearner) who is currently conducting stem cell research in Germany.
What is life? A biologist tries to give a definition of life.
🔬 Subscribe for more awesome biomedical research: bit.ly/2SRMqhC
🔬Me being funny on other media:
Twitter: twitter.com/CSteinek
Discord: discord.gg/9VKnTSF
What is Life? It is quite difficult to give a short definition of life. However, we can try to define life by looking at some characteristics of life forms. Robert Hooke and Anton van Leeuwenhoek were the first ones to describe cells. Cells contain a variety of organelles which are enclosed by a membrane. In the 20th century, Erwin Schroedinger said in his book "What is life?" that life seems to defy the second law of thermodynamics. However, complex biochemistry and membranes help to overcome this law of physics. Besides having cells, life also has DNA or RNA which stores information to make a cell. All living organisms use DNA or RNA to make RNAs and proteins. Waddington stated that the regulation of DNA is necessary to decide cell fate. Many cells of our bodies have the same DNA but different sets of active genes. Organisms are also responsive and grow and develop through interactions with their environments. Moreover, life is also defined by reproduction. Through reproduction DNA can be passed down to future generations. Charles Darwin defined the process of evolution where mutations (genetic variations) lead to different reproductive successes through natural selection.
Viruses are often not considered to be alive as they are in great need of a host. Sir Paul Nurse, however, argues that they might be considered alive given that many organisms depend on other organisms. All in all, life is extraordinary.
Great inspirations:
"What is life?" by Erwin Schrödinger
"What is life?" by Sir Paul Nurse
Images:
Some pictures were derived from Servier Medical Art by Servier. You can find over 3000 free medical images here: smart.servier.com
Single Cell by Videezy, CCA 4.0
Biology by CNX OpenStax, CCA 4.0
SJ8&18-2 cells by AbdyMabbett (Carl Zeiss Microscopy), CCA 2.0
Francis Crick by Marc Lieberman, Materialscientist, CCA 2.5
Rosalind Franklin by MRC Laboratory of Molecular Biology, CC-BY 4.0
Wuthering Heights family tree by shako, CC-BY 3.0
Tree of life by Maulucioni, CC-BY 3.0
Fossil of Seymouria By Sanjay Acharya, CC-BY 4.0
Darwin Finches by the Wellcome Trust, CC-BY-4.0
Cellular Respiration by RegisFrey, CC-BY-3.0
Museo del Mamut by Thomas Quine, CC-BY 2.0
Way to Chirbasa by Dibendu Nandi, CC-BY 4.0
Sir Paul Nurse by the University of Exeter, CC-BY 2.0
Plasdomium falciparum by Calicut Medical College, CCA-BY 4.0
Music:
Title: No. 4 Piano Journey
Artist: Esther Abrami CCA
Title:Not For Nothing
Artist: Otis McDonald CCA
Title: Luminance
Artist: Scott Buckley soundcloud.com/scottbuckley (promoted by Audio Library youtu.be/yTl_PtnDwEY) CCA
About Clemens Steinek:
CLEMENS STEINEK is a postgraduate student/youtuber (LifeLabLearner) who is currently conducting stem cell research in Germany.
