Answer:
Isotopes of an element share the same number of protons but have different numbers of neutrons. Let's use carbon as an example. There are three isotopes of carbon found in nature – carbon-12, carbon-13, and carbon-14. All three have six protons, but their neutron numbers - 6, 7, and 8, respectively - all differ.
Explanation:
Answer: Km = 10μM
Explanation: <u>Michaelis-Menten constant</u> (Km) measures the affinity a enzyme has to its substrate, so it can be known how well an enzyme is suited to the substrate being used. To determine Km another value associated to an eznyme is important: <em>Turnover number (Kcat)</em>, which is the number of time an enzyme site converts substrate into product per unit time.
Enzyme veolcity is calculated as:
![V_{0} = \frac{E_{t}.K_{cat}.[substrate]}{K_{m}+[substrate]}](https://tex.z-dn.net/?f=V_%7B0%7D%20%3D%20%5Cfrac%7BE_%7Bt%7D.K_%7Bcat%7D.%5Bsubstrate%5D%7D%7BK_%7Bm%7D%2B%5Bsubstrate%5D%7D)
where Et is concentration of enzyme catalitic sites and has to have the same unit as velocity of enzyme, so Et = 20nM = 0.02μM;
To calculate Km:
![V_{0}*K_{m} + V_{0}*[substrate] = E_{t}.K_{cat}.[substrate]](https://tex.z-dn.net/?f=V_%7B0%7D%2AK_%7Bm%7D%20%2B%20V_%7B0%7D%2A%5Bsubstrate%5D%20%3D%20E_%7Bt%7D.K_%7Bcat%7D.%5Bsubstrate%5D)
![K_{m} = \frac{E_{t}.K_{cat}.[substrate]-V_{0}*[substrate]}{V_{0}}](https://tex.z-dn.net/?f=K_%7Bm%7D%20%3D%20%5Cfrac%7BE_%7Bt%7D.K_%7Bcat%7D.%5Bsubstrate%5D-V_%7B0%7D%2A%5Bsubstrate%5D%7D%7BV_%7B0%7D%7D)

Km = 10μM
<u>The Michaelis-Menten for the substrate SAD is </u><u>10μM</u><u>.</u>
time travel is the best option