Origin of life Flashcards
Evolution from monomers to complex cells (15 cards)
What are coacervate droplets?
A special type of microsphere that can form under appropriate conditions of temperature, ionic composition, and pH
Coacervates are believed to be one of the precursors to life.
What can coacervates absorb from their environment?
Molecules known as ‘nutrients’
These nutrients are essential for coacervates to perform their functions.
What is one example of a nutrient that coacervates can absorb and convert?
Glucose phosphate
Coacervates can convert glucose phosphate into maltose.
What limited ability do coacervates possess?
Catalytic ability to break down nutrients
This ability is limited compared to more complex biological systems.
Do coacervates have the ability to grow?
Yes
Growth is an essential characteristic for potential life forms.
What may eventually form around coacervates if lipids are absorbed?
A semipermeable membrane
This membrane is crucial for maintaining the internal environment of coacervates.
Can coacervates reproduce?
Only reproduce experimentally
This indicates that they do not meet all criteria to be classified as alive.
True or False: Coacervates can be considered alive.
False
They cannot be classified as alive since they only reproduce under experimental conditions.
Who, through an experiment showed that monomers could polymerise
Sydney Fox
What were the products of Stanley Miller’s experiment?
All 20 amino acids, some sugars, nucleotides of DNA & RNA, lipids and Adenosine triphosphate (ATP)
What are the conditions needed for coarcavate to form?
Suitable temperature, ionic composition and pH
Which characteristics of a coarcavate makes it similar to a cell?
It can reproduce (experimentally), it has the ability to grow, it can absorb molecules or ‘nutrients’ from the environment (has limited ability to break the nutrients down) , it can have a semipermiable membrane if it absorbs a lipid from the environment
Explain how the ideas of Charles Darwin changed the Pre- Darwin thinking on the origin of species
Pre-Darwin thinking : Fixity of species (Carolous Linnaeous), short age of earth, spontaneous generation (Louis Pasteur), ladder of nature (Aristotle) and catastrophism ( Cuvier)
Post - Darwin thinking : Natural selection, descent by modification (common ancestor) and gradualism (uniformitarianism - Charles Lyell)
What are the favourable conditions for the origin of life?
No oxygen
Energy source(s) - heat, solar radiation, lightning and radioactivity
Chemical molecules for the energy source(s) to work on
Lots of time
What was the first bacteria to evolve modern photosynthesis?
Cyanobacteria
