Chapter 10 - Flashcards
What is the active site
It is the part of an enzyme that combines with the substrate
It is specific to a single substrate
What is the induced fit model
When the substrate causes the active site to change shape so that it fits more precisely around the substrate
Describe the mechanism of induced fit model
- Substrate combines with the active site
- Active site changes shape slightly to fit substrate
- Enzyme substrate complex forms - bonds altered, substrate changed to product
- Products leave active site - active site returns to original shape
What are the active sites optimum conditions
Active site is sensitive to ph and temperature
Optimum range:
for ph - 6-8
For temperature - 37 in humans and 20-30 in plants
What is denaturation
Change in ph or increase in temperature causes the enzyme to lose it’s shape and no longer carry out its function
what is the difference between ATP and ADP?
ADP - low energy molecule, stable molecule
ATP - high energy molecule, unstable bond, cannot store energy for very long, energy used for cellular reactions
ATP and ADP are interconvertible, what does this mean?
they can both be made into each other
ADP + energy + P —-> ATP + water
ATP + water —-> ADP + energy + P
what is cellular reaction is NAD+ used in?
respiration
how does NAD+ change to NADH?
it combines with 2 high energy electrons (e-) and a proton (H+)
what is the chemical equation for the change from NAD+ to NADH?
NAD+ + 2e- + H+ —> NADH
how does NADH convert back to NAD+?
it releases energy and protons and breaks down to NAD+
what does NAD stand for?
nicotinamide adenine dinucleotide
what does NADH stand for?
nicotinamide adenine dinucleotide + hydrogen
what does NADP stand for?
nicotinamide adenine dinucleotide phosphate
when is NADP and NADPH used?
photosynthesis
