Grant’s DNA sample has a concentration of 45µg/mL, and he has 350µL of solution. Which of the following answers would allow him to run the proper amount of DNA on a quality control gel?

A) He should dilute the sample 1:10 and load 10uL on the gel
B) He should complete 2 1:10 serial dilutions and load 10uL of the second dilution on the gel
C) He should load 10uL of the undiluted sample on the gel
D) He should load 100uL of the undiluted sample on the gel
E) He does not have enough DNA to run a quality control gel

To determine the proper amount of DNA to run on a quality control gel, we need to calculate the concentration of DNA that should be loaded onto the gel.

Given:
DNA sample concentration = 45µg/mL
Volume of solution = 350µL

First, we need to calculate the total amount of DNA in the solution:
Amount of DNA = concentration × volume
Amount of DNA = 45µg/mL × 350µL
Amount of DNA = 15,750µg

A quality control gel typically requires a specific amount or concentration of DNA to be loaded for accurate results. Without that information, we can't accurately determine the proper amount of DNA to load on the gel.

From the given answer choices:
A) Diluting the sample 1:10 and loading 10µL on the gel means the loaded DNA would be at a concentration of 4.5µg/mL (45µg/mL ÷ 10).
B) Completing 2 1:10 serial dilutions and loading the second dilution means the loaded DNA would be at a concentration of 0.45µg/mL (4.5µg/mL ÷ 10).
C) Loading 10µL of the undiluted sample means the loaded DNA would be at a concentration of 45µg/mL.
D) Loading 100µL of the undiluted sample means the loaded DNA would be at a concentration of 45µg/mL.
E) The given information does not indicate that there is not enough DNA to run a quality control gel.

Without knowing the specific concentration or amount of DNA required for the quality control gel, we cannot determine the correct answer.

To determine the proper amount of DNA to run on a quality control gel, we need to calculate the total amount of DNA in Grant's DNA sample and compare it to the recommended amount.

Given:
Concentration of DNA sample = 45 µg/mL
Volume of DNA solution = 350 µL

First, let's calculate the total amount of DNA in Grant's DNA sample. We can use the formula:

Total amount of DNA = concentration × volume

Total amount of DNA = 45 µg/mL × 350 µL

Total amount of DNA = 15,750 µg

Now, let's analyze the answer choices:

A) Dilute the sample 1:10 and load 10 µL on the gel.
To dilute the sample 1:10, we would mix 1 part of the DNA sample with 9 parts of diluent. This means we would have 10 parts of the diluted sample. Therefore, the concentration of the diluted sample would be 1/10th of the original concentration. In this case, the diluted concentration would be 4.5 µg/mL (45 µg/mL ÷ 10). Multiplying this diluted concentration by the volume to be loaded (10 µL) gives us 45 µg. This is less than the total amount of DNA (15,750 µg), so it is not the proper amount.

B) Complete 2 1:10 serial dilutions and load 10 µL of the second dilution on the gel.
Using the logic from option A, we can calculate the concentration and amount of DNA in the second dilution. The first dilution would have a concentration of 4.5 µg/mL (1/10th of 45 µg/mL), and the second dilution would also have a concentration of 4.5 µg/mL. So, the total amount of DNA in the second dilution would be 4.5 µg/mL × 350 µL = 1,575 µg. This amount is still less than the total amount of DNA, so it is not the proper amount.

C) Load 10 µL of the undiluted sample on the gel.
The total amount of DNA in the undiluted sample is 15,750 µg, which is greater than the previous calculations of 45 µg and 1,575 µg. So, loading 10 µL of the undiluted sample on the gel would be proper.

D) Load 100 µL of the undiluted sample on the gel.
The amount of DNA we would have by loading 100 µL of the undiluted sample would be 45 µg/mL × 100 µL = 4,500 µg. This is greater than the total amount of DNA, so it is not the proper amount.

E) Grant does not have enough DNA to run a quality control gel.
The previous calculations show that Grant's DNA sample has a total amount of 15,750 µg of DNA. This is sufficient to run a quality control gel.

Therefore, the correct answer is option C) Grant should load 10 µL of the undiluted sample on the gel.