chemistry of life Flashcards
What does the search for extraterrestrial life force us to define?
The word life
The search for extraterrestrial life mainly takes the form of a search for what?
chemical signatures of life
what is the copernicus principle
We are not the center of the solar system (the sun it) how far does it go?
we are not special
what are the attributes of life?
6
things must grow and reproduce
surrounded by a selective barrier
must transform matter to energy (metabolism) (free energy)
must produce large, complicated molecules
sense and respond to stimuli
must evolve
why is life said to be carbon based?
Because carbon has felxible bonding properties that allows it to form a huge variety of molecules. apart from water almost all molecules found in cells have carbon in them
what characteristic do most carbon containing molecules have?
most are chiral
-is a molecule that cannot be superimposed in its mirror image
How does carbon make a molecule chiral?
The presence of a carbon atom with four different atoms of groups of atoms attached to it makes it chiral
What happens when you have a organic molecule that can exist in two mirror-image forms?
Only one of the forms is found in life
why do water molecules stick together?
Due to the hydrogen bonds between the water molecules
most molecules of life are what?
soluble in water (hydrophilic)
What are the molecules that are not soluble in water called?
Hydrophobic and are used to create barriers within cells and around cells
Most biochemical reactions take place in what type of environment?
Aqueous environment
function of sugar(3)
Energy storage
energy transport
carbon skeletons for modification
Function of a polysaccharide (2)
Energy storage
structural support
types of lipids (4)
Fatty acid- components of larger lipid molecules
triglycerides (solid fats and liquid oils)- energy sources and storage
phospholipids - compounds of membranes around cells and around compartments within cells
sterols-chemical signalling and membrane stabilization
