Unit 2: Metabolism and Survival - Key Area 1: Metabolic Pathways Flashcards
define anabolic reactions
metabolic activity that requires energy input and builds up larger molecules from smaller ones
define catabolic reactions
metabolic activity that releases energy from reactions which break down large molecules into smaller ones
define a metabolic pathway
integrated and controlled pathways of enzyme-catalysed reactions within a cell.
define metabolism
sun total of all the chemical reactions that take place in a living cell
what is a phospholipid membrane
membrane of a cell made from fluid phospholipid molecules and proteins
what is a pore
small gap in a membrane created by a channel-forming protein
what is a pump
protein in a phospholipid membrane that carries substances across it by active transport
what are the types of steps present in metabolic pathways
reversible, irreversible and alternative routes
what do membranes consist of?
protein and phospholipid
what is the function of a phospholipid molecule
forms a double layer and are in constant motion giving a fluid nature to membranes making them flexible
what is the function of channel forming proteins
channel forming proteins have pores which control the diffusion of certain molecules depending on their size. These potes make cell membranes selectively permeable.
define active transport
the movement of molecules from low to high concentration. this type of movement needs additional energy that is available from ATP.
what is an example of a carrier protein involved in active transport
sodium-potassium pump
give an example of an enzyme embedded in the membrane
ATP synthase, embedded in the membranes of mitochondria and chloroplasts where it catalysés the synthesis of ATP
