lecture 7 Flashcards
1
Q
facts about energy
A
- all living things require energy (mainly from sun)
- some organisms gain energy from oxidation of inorganic compounds - independent of solar system
- photosynthesis - herbivores - carnivores - decomposers
2
Q
what is metabolism
A
the sum total of all the chemical reactions that take place in a cell
3
Q
types of reactions
A
exergonic: a reaction will only proceed spontaneously if it liberates energy
endergonic: reactions require an input of energy to process
4
Q
what is energy of activation
A
- substrates need to be activated before a reaction takes place
- reactions catalysed by enzymes - enzymes lower energy required for activation of a reaction
5
Q
what is an enzyme
A
they are proteins that bind reactants to active sites creating the enzyme - substrate complex (reaction occurs on enzyme)
6
Q
what is a metabolic pathway
A
a series of enzymes catalyse in a set of linked reactions
7
Q
what factors effect enzyme activity
A
- temp
- pH
- substrate concentration
- enzyme concentration
- cofactors: enzymes require vitamin coenzymes in metal ions to function
8
Q
what is photosynthesis and respiration
A
matter and energy are cycled through chloroplasts and mitochondria to give life to living things
