Learning check
Once you have watched the video, check your learning with this quiz.
The science of life
What does the word "biology" mean?
- Greek ”bios” = life
- Greek ”logos” = text, knowledge of
- Bio-logy = science of life
But ...
What is life?
Something that …
- … has a metabolism.
- … can grow and reproduce.
- … has the ability to move.
- … can evolve (develop) over time.
A methane molecule consists of four hydrogen atoms (white) bound to a carbon atom (black). It is not alive.
An adenine molecule also has some nitrogen atoms (blue). It is not alive.
Adenosine monophosphate also contains some oxygen atoms (red) and a phosphorous atom (yellow). It is not alive.
Several adenosine monophosphate molecules may be joined to form polyadenine. It is still not alive.
Several nucleotides (of which adenosine monophosphate is one) may be linked together like this. Although this is actually a DNA molecule, it is still not alive.
Cells – the smallest living units:
- Cellular membrane to keep everything in place.
- DNA and RNA (genetic material).
- Enzymes (a kind of proteins) coordinate the metabolism.
A very simple bacterial cell with cellular membrane (blue), DNA (orange), and enzymes (green).
