The emergence of macromolecules

Question 1

How is life ‘handed’?

Answer 1

Although both enantiomers occur frequently, life uses exclusively R-handed sugars and L-handed amino acids

Question 2

How does Christopher Dobson believe the ancient ocean could have given rise to a lipid bi-layer?

Answer 2

• airborn water particle contains amphiphile lipids which self organise around the droplet forming a membrane
• when the droplet falls back to the ocean gets envolved in another layer of lipids, forming a bilayer around the droplet

Question 3

How does David Dreamer believe biological molecules could have emerged in hydrothermal pools?

Answer 3

• Layers of lipid build up on the edges of the pool, trapping chemicals and encouraging the growth of RNA
• Lipid-bound droplets may have formed creating RNA-filled protocells

Question 4

What have David Dreamers experiments found?

Answer 4

That AMP (adenoside monophosphate) and UMP (uridine monophosphate) nucleotides of RNA can self-assemble if you trap them between a layer of lipids and incorporate wet/drying cycles

Question 5

How could clay have helped form pre-biotic macromolecules?

Answer 5

• Its weak bonds between layers allow impurities to enter and its electrically charged surface attracts and binds molecules
• Has a large reactive surface area
• Are found to assist RNA nucleotides to self assemble, as well as lipid vesicles