metabolic pathways 2.1 Flashcards
cell metabolism
the sum of all biochemical reactions which take place in living cells
break down of larger molecules into smaller molecules which results in energy being released
catabolic pathways
small simple molecules joining together to form a larger complex molecule which requires energy
anabolic pathways
ATPs role is to transfer energy between ……. reactions and ……….. reactions in cells
catabolic
anabolic
why do alternative routes for metabolic pathways exist
if a specific enzyme or substrate isnt available in the pathway
what are membranes composed of
phospholipids and proteins
forms channels or….. across the membrane
allows diffusion of larger molecules
protein pores
-molecules move from higher to lower concentration down a concentration gradient
-passive process
diffusion
transports molecules by active transport
from lower to higher concentration against against the concentration gradient
requires energy provided by ATP
protein pumps
catalyse steps in metabolic pathways
e.g. ATP synthase
proteins as enzymes in cell membranes
how do enzymes speed up biochemical reactions
lowering the activation energy
why are enzymes necessary
because biochemical reactions must take place at a fast enough rate for survival
what happens to the active site when the substrate binds to the enzyme
the enzyme changes shape slightly to better fit the substrate this is induced fit.
the substrate has a ………… affinity for the active site
high
the subsequent products have a ……. infinity allowing them to leave the active site
low
